Send corrections and updates to Andy McFadden. If you have a question you'd like to see answered in here, either post it to one of the comp.publish.cdrom newsgroups (if you don't have the answer), or send it to firstname.lastname@example.org (if you do).
This FAQ is usually updated about once a month. If you are looking at a version that is more than two or three months old, it may be an out-of-date copy. The most current version is always at http://www.cdrfaq.org/.
This was originally developed (and is still maintained) as a Usenet newsgroup FAQ. If you'd like to check out the newsgroups, point your news reader at the following (or go to http://newsone.net/ and read them with your web browser):
The "canonical" FAQ is available from http://www.cdrfaq.org/ in HTML format and from the MIT FAQ archives in plain text format. You can get an all-in-one-file version of the HTML in a .ZIP file, suitable for printing. Some translations are available:
If you're maintaining a translation, or just really want to know what has changed since the last update, you can get a set of context diffs in a .ZIP file.
Please DO NOT post copies of the HTML version on your web site unless you plan to keep them up to date automatically. I have on several occasions received e-mail from people reading versions that are several months old. Just use a link to the www.cdrfaq.org site instead.
|Search www.cdrfaq.org pages with Google:|
The last-modified date of each section is shown below the Subject line. The date format used is YYYY/MM/DD. The date stamps were added on 1998/04/06, so you won't find any older than that.
This version of the FAQ is generated automatically by faq2html, an application developed specifically for converting the plain ASCII version of the CD-Recordable FAQ to HTML. The program is available in source form.
This document is Copyright (C) 1996-2003 by Andy McFadden, All Rights Reserved. All of the content here, except for attributed quoted material, is my original work.
Free distribution of the this FAQ is encouraged, as are conversions to HTML or other formats and translation to foreign languages, so long as no content is removed, and additions are clearly marked.
The plain ASCII text and www.cdrfaq.org HTML versions aren't otherwise restricted, but other conversions might be (the content is free, the presentation or translation might not be). Check with the publisher.
The date and version number on the FAQ *are* considered part of the content that must not be removed. I occasionally get messages from people who don't realize that the copy they're reading is more than a year and a half old.
Caveat lector: the information here is derived from Usenet postings, e-mail, and information on WWW sites. As such, it may well be DEAD WRONG, and you are encouraged to verify it for yourself.
I take no responsibility for damaged hardware, CD-Rs turned into coasters or frisbees, time lost, or any other damages you incur as a result of reading this FAQ. Information on specific models of hardware and software is based on *opinions* of other users, not scientific studies. I am not an expert in this (or any other) field. Everything here could be a total malicious lie, and should be treated as such. You have been warned.
I don't get paid to plug anybody's software or equipment. The sections on "what XXX should I buy" are not here because I want to sway purchases one way or another, they're here because the questions are asked *a lot*, and the answers are pretty consistent. You are invited and encouraged to investigate the capabilities and reputations of all products.
The various product and company names are trademarks of their respective companies.
Visit http://www.clari.net/brad/copymyths.html for a mini-FAQ on copyright laws.
This document attempts to answer Frequently Asked Questions about Compact Disc Recordable technology and related fields. It was originally developed as a Usenet newsgroup FAQ, and is updated and posted around the middle of each month. The main foci are explaining CD-R technology, describing hardware and software solutions for creating audio CDs and CD-ROMs, and helping people find solutions to common problems.
The FAQ is heavily biased toward PCs and computer-based recorders, because that's what I'm most familiar with, but I have made an effort to include useful information for owners of other equipment. I don't anticipate the section on stand-alone audio CD recorders expanding greatly, because they're far simpler to operate than computer-based recorders, and most of the "must know" information about them is more appropriate in an FAQ on stereo systems or studio recording. I do try to address deficiencies in Macintosh coverage.
I don't usually address questions that can be phrased, "how do I make my software do this?" The answers to those should be in the manual that came with your software. In general, this is a collection of answers to specific questions, not a "how to" guide. I have tried to make the answers easy to understand by an inexperienced user, but if you know absolutely nothing about recording CDs then some sections may be confusing.
This is not a newsletter. Actively maintained web sites are a much better source of breaking news than this document, which is updated at most once a month. I also don't try to track moving targets, like CD recorder firmware versions or software versions unless a specific release is especially interesting. Ditto for which recorders work with which packet-writing solutions, or which recorders can overburn.
This FAQ does not, and will not, cover DVD, DVD-ROM, DVD-R, DVD-RAM, DVD+RW, or any of the other formats in the ever-expanding DVD morass. There are other resources on the web for DVD topics.
You will not find a lot of detail about "backing up" copy-protected software, or where to find unlock codes or "warez". There are many web sites that explain these matters at length.
All sections are tagged with a modification date, so you can see how long ago something was revised. If you want to know *everything* that has changed since last time, you can get a set of "context diffs" from http://www.cdrfaq.org/txtdiffs.zip.
Added sections (2-46), (6-7-16).
There are a few translations available.
Hungarian, by Nagy Szabolcs: http://delfin.klte.hu/~nagysz/cdrgyik/.
French, by Marc Kergomard: http://www.lagravuredecd.com/.
Russian, by Oleg Nechay: http://members.tripod.com/greatkorzhik/cdrfaq.htm.
Italian, by Marzona Simone: http://web.tiscali.it/marzonaontheweb/faq/faq.html.
Italian, by Simone Parca: http://digilander.iol.it/cdrfaq/ (an older version; formerly at users.iol.it/parsi/).
Spanish, by [[[CAM]]]: http://cdrfaq.webcindario.com/CDRfaq.htm.
French, German, Italian, Portuguese, and Spanish translations can be done through http://babelfish.altavista.com/translate.dyn. This is an automatic language translator that is HTML-aware. It only translates the first part of each document, so it's not entirely helpful if you just want to read a translation, but it may make doing a full translation much easier. (The translation is pretty good for an automatic translator, but is still pretty rough. I don't want to post a translation that is inaccurate or misleading, so I'm not going to run the FAQ parts through babelfish automatically.)
If you're interested in translating this FAQ, you are welcome to do so, but please respect the amount of work that I and others have put into it. Don't strip out sections, remove author attributions, or hide the revision date of the document. I don't think the terms in section (0-1) are terribly restrictive. If, for whatever reason, you can't keep up with every update of the English version, that's fine; all I ask is that you include a link to the www.cdrfaq.org version, so that the current information is easily locateable. (Some commonly updated things, like the list of recorders in section (5-1), don't need much translation.) If you don't want to translate a particular section, just leave it in English.
If you want to start with an HTML version, use the pages from http://www.cdrfaq.org/. If you prefer to do the translation on a text document, and you're converting to an iso-latin language, the "faq2html" converter that I use can be found in the "downloads" section on http://www.fadden.com/.
If you do a translation, let me know and I'll put the URL here.
This FAQ covers the three newsgroups in the comp.publish.cdrom hierarchy, one for software, one for hardware, and one for multimedia. The names of the newsgroups imply that the intended topics are related to publishing material on CD-ROMs, but the current discussions cover most everything related to CD-Recordable devices.
Here are a few guidelines. These aren't hard and fast rules -- nobody died and put me in charge of making the rules -- but if you're not sure what the appropriate subject matter is then this may be helpful.
news:comp.publish.cdrom.hardware is the most popular of the groups. Appropriate material includes questions about past, current, and future CD-R devices. Asking for installation help or advice on what to buy is appropriate, as are questions about related hardware like SCSI adapters and CD-ROM drives. Some related newsgroups are:
news:comp.sys.ibm.pc.hardware.cd-romnews:comp.publish.cdrom.software is for discussions about software used to prepare material for and create CDs and CD-ROMs. Questions about how to do things with a specific piece of software belong here, as do "the CD-R software from XXX won't recognize my drive", and "does a program exist that does YYY". Some related newsgroups are:
news:alt.cd-romnews:comp.publish.cdrom.multimedia is for discussions about creating multimedia products on CD-ROMs. Questions about multimedia authoring software belong here, as do most production-type questions, e.g. "where can I go to get my CD pressed with jewel cases and glossy inserts?" Related newsgroups are:
news:comp.multimediaPlease try to keep cross-posting to a minimum. Broadcasting questions to 3 or 4 related newsgroups will increase the noise level and probably won't get you more answers.
Some general rules apply to all of the comp.publish.cdrom.* groups:
(1) Piracy of CD-ROM software or CDs: CD recorders can be used to make copies of copyrighted material, and while backups of data are legal, making or accepting copies from others most likely isn't. Whatever your opinion of the matter, software piracy and other copyright violations are illegal in most countries in the world, so requests and/or advertisements for pirated material should be kept off the newsgroup. Also, please don't start or participate in a debate about whether or not software piracy is bad. There have been hundreds of such debates over the past several years, and the only thing that either side has managed to prove is that piracy debates are a tremendous waste of time.
(2) Personal CD-R hardware and software sales: strictly speaking, these groups aren't appropriate for selling off your old hardware or software. Such things are best left in misc.forsale.computers.*, ba.market.computers, and related groups. Since many readers are in the market for new hardware, a limited number of clearly marked articles are tolerated. The common Usenet convention is to use "FS: HP4020i $400 obo" for "For Sale" messages and "WTB: HP4020i" for "Want To Buy" messages.
(3) CD-R product advertising: these groups by their nature are somewhat commercial. Many readers are in the market for new hardware or CD-R media, and for this reason a *limited* amount of retail/wholesale advertising is tolerated but discouraged. If you *clearly* mark your postings as advertisements, you will get relatively few complaints. Posting frequent and useless followups just to broadcast your 20-line signature will get you flamed and subsequently ignored. Feel free to send mail to people who post questions about product pricing and availability, but please don't create mailing lists and broadcast to everyone who posts.
(4) Other advertising: while it's certainly the case that most or all of the readers have a CD-ROM drive on a computer, the same could be said of almost every person reading news from a home computer today. Please keep ads in newsgroups that are more appropriate. Advertising the latest educational, game, or adult CD is inappropriate for these groups, as are "hot new Cyrix 686 PC" posts. Subtle attempts to advertise web sites ("golly, this looked really neat, so I thought I'd tell everyone") are more obvious than you might think.
(5) Spam: you cannot make money fast. That's life, get used to it. If the message involves putting your name at the top of a list of 5 or 10 people, don't post it. If it has an 800 or 888 number that a reader would call to hear more about your unique business opportunity, don't post it.
(6) Job postings: looking for job candidates on these newsgroups is a tolerated but generally futile exercise. Most of the readers are looking for or offering help on CD-Rs, not searching for a job. Try one of the other groups, like misc.jobs.offered.
(7) Binaries: as with most Usenet newsgroups, posting binary files (large or small) is inappropriate. If you want to make a binary file available to Usenet readers, send it to an appropriate alt.binaries newsgroup, and just post a pointer to it in the other group(s).
One final note: bear in mind that these groups are read by people all over the world. If you're looking for local retailers, be sure to specify what "local" is for you. Posting in English is the best way to ensure that you will get a response, but the readership is diverse enough that you will likely get a reply no matter what language you use. If you want to quote prices, specify the currency to avoid confusion (e.g. US$300 or CAN$300 or Y30000 or ...).
The first thing to do is look at the web pages for the products you're using. Sometimes there will be software or firmware updates, or pages with information on common problems. Doing a web search or scanning through news archives on servers like Google Groups (http://www.google.com/) will often turn up relevant material.
If you don't find anything, calling or sending an e-mail message to the technical support department for the product that is giving you trouble is a good second step. If you want to contact other users, posting a message to one of the Usenet newsgroups is a reasonable thing to do.
You will get faster, more accurate responses to questions if you include enough detail in your mail message or news posting. For most problems having to do with recording, you need to specify:
Whenever possible, the FAQ tries to use the correct spelling and terminology. Errors should be reported to the FAQ maintainer, but bear in mind that I don't modify the contents of quoted material, the names of products, or the titles of articles and web pages.
Some common mistakes are:
(1) Writing "CDROM" instead of "CD-ROM". It should be CD-ROM, CD-R, CD-RW, and CD-DA, not CDROM, CDR, CDRW, CDDA.
(2) Writing "disk" instead of "disc". The words have the same meaning, but are spelled differently in different countries, just like "color" and "colour". By convention, CDs are called "discs", while hard drives and floppies are called "disks". "Disc-to-disc" copies are different from "disk-to-disc" and "disc-to-disk" copies!
(3) Referring to a sector as a "frame". On a CD, the basic allocation unit visible outside the firmware is the 2352-byte sector (sometimes called a "block"). A "frame" is a structure at a lower level. There are 24 bytes in a frame, and 98 frames in a sector (24*98 = 2352).
Not really. In an effort to keep the FAQ fair and impartial, I don't accept advertising. Vendors with relevant products can have URLs added to appropriate sections of the FAQ. Vendors without URLs for their products aren't usually listed.
Products that solve specific problems, such as recovering data from damaged discs, repairing scratches, or removing pops and clicks from digitized audio tracks, will be listed under the appropriate topic. CD recording software and hardware vendors can get their own sub-section. Vendors that don't fit in a specific category will be listed in section (8).
I'm not set up to act as a mail server, but some other places are. You can request a copy of the FAQ from rtfm.mit.edu's mail server like this:
send faqs/cdrom/cd-recordable/part1The mail server breaks each part into smaller pieces, so you will end up with about a dozen mail messages when all is done.
You can get a full FAQ list on "accessing the Internet through e-mail" from http://www.faqs.org/faqs/internet-services/access-via-email/ or by mail request:
send usenet/news.answers/internet-services/access-via-emailDon't put anything else in the body of these messages; just one or more "send" lines. The "subject" line is ignored.
These are intended to be brief (if somewhat incomplete) answers to basic questions. More detailed information can be found later in the FAQ. For example, section (1-5), "How much can they hold?", is answered in far more detail in section (7-6).
CD-R is short for "CD-Recordable". Recordable CDs are WORM (Write Once, Read Multiple) media that work just like standard CDs. The advantage of CD-R over other types of optical media is that you can use the discs with a standard CD player. The disadvantage is that you can't reuse a disc.
A related technology called CD-Rewritable (CD-RW) allows you to erase discs and reuse them, but the CD-RW media doesn't work in all players. CD-Rewritable drives are able to write both CD-R and CD-RW discs.
All CD recorders can read CDs and CD-ROMs, just like a standard CD-ROM drive.
The CDs you buy in a store are pressed from a mold. CD-Rs are burned with a laser. They may look different (often green, gold, or blue instead of silver), they're less tolerant of extreme temperatures and sunlight, and they're more susceptible to physical damage. Whether CD-Rs or pressed CDs last longer is difficult to answer.
While they're not physically identical, they work just the same. Some CD players and CD-ROM drives aren't as good at reading CD-R and CD-RW discs as they are at reading pressed CDs, but by and large they work just fine.
By the way, you can't record on pressed discs, so you might as well throw out all those AOL CD-ROMs you've been accumulating. Buying a bunch of old CDs in the hopes of writing new stuff onto them is a bad idea. For similar reasons you can't record on DVD media, not even DVD-R and DVD+RW, unless your drive explicitly supports the DVD formats. You have to buy blank CD-R or CD-RW media.
Yes. You can create CD-ROMs from data on your hard drive, and you can create new audio CDs from anything you can record into a WAV or AIFF sound file. With an audio-only CD-Recorder, which hooks up to your stereo system instead of your computer, you can record directly from CD, cassette, DAT, or whatever.
The CD-ROMs you produce will play in ordinary CD-ROM drives, and the audio CDs you create will work in your home or car CD player.
Writing to CD-Rs and CD-RWs requires a CD recorder. You can't write CDs with an ordinary CD-ROM drive.
One of the more popular things to do with a CD recorder is make copies of old cassettes and LPs. See section (3-12) for information about this.
Yes, both audio and data CDs can be duplicated. You can even create audio CDs that are compilations of other audio CDs (perhaps a personal "best of" disc).
Bear in mind that most CDs are protected by copyright laws.
About 74 minutes of audio, or about 650MB of data.
Some CD-R blanks can hold 80 minutes of audio, or about 700MB of data.
See section (7-6) for more info.
Yes and no. The process can be a bit more involved than that, and requires software that (usually) comes bundled with the drive.
With "packet writing" software, and a recorder that supports it, you can treat a CD-R or CD-RW disc like a floppy. On a CD-R you can only write to each part of the disc once, so deleting files doesn't gain any space. There are other limitations as well.
With more traditional software -- necessary if you want broad compatibility -- you usually end up writing everything to the disc all at once. When you're doing the writing you can't interrupt the drive, and you can't reclaim the space you've used. If you want to write your files in smaller bunches, you lose a fair bit of space every time you stop and start again.
Nothing. This FAQ is about CD-R and CD-RW, and only crosses over into DVD when the two technologies rub up against each other.
To learn more about DVD, see section (2-14) and check out the DVD FAQ at http://www.dvddemystified.com/dvdfaq.html. For DVD recorders, check out the Usenet newsgroup alt.video.dvdr and perhaps rec.video.dvd.tech.
Not directly. CD and DVD are very different formats, so you can't write DVDs with your CD recorder. You may be able to convert the contents into a lower-quality format though. Be wary of scams. See section (3-49).
There are devices now that can record both DVD-R and CD-R. Those are usually advertised as "DVD recorders", not "CD recorders".
I don't know. I don't track prices. There are web sites dedicated to finding the lowest prices, and you can do a little research with a web browser, starting perhaps with the vendors listed in section (8-3).
Yes, from the manual that comes with your recorder and software. There's no information of this type in the FAQ because there are far too many permutations of hardware and software, and the instructions would have to be updated with every new release of the software.
Yup. You can download MP3s, write them to a CD, and play it in anything that handles audio CDs. In fact, many of the popular CD recording programs will decode the MP3s for you.
It's also possible to take songs from a CD and convert them to MP3s for use in an MP3 player.
Section (3-27) has more details.
There are some good glossaries on the web. Try these:
You only need "music" blanks if you have a "consumer" stand-alone audio CD recorder. If you have a recorder attached to your computer or a "professional" deck then the "music" blanks will work no better or worse than "data" blanks.
See section (7-17) for details.
This FAQ contains a great deal of information, but it's geared toward answering specific questions rather than providing a general education. Some of the other net resources are more like a tutorial than a Q&A list, and may provide a better starting point.
Mike Richter has a primer on CD-R at http://www.mrichter.com/.
Roxio has some good information at http://www.roxio.com/en/support/.
If you're new to CD recording and are feeling a little lost, you may want to buy a book on the subject. Try one of these:
You may be reading an out-of-date copy of the FAQ. Some sites like to make a copy of the FAQ with the version, date, and contact information stripped off the top (in violation of section (0-1)), which makes it hard to tell when it was last updated. The FAQ is updated about once a month, and the most recent version is always available from http://www.cdrfaq.org/.
If you are reading the current version, either the section hasn't been updated in a while (check the date in the section), or something has slipped past me.
If you want news articles updated daily, try the sites in section (8-4).
From _The Compact Disc Handbook, 2nd edition_ by Ken Pohlmann, 1992 (ISBN 0-89579-300-8):
"Write-once media is manufactured similarly to conventional playback-only discs. As with regular CDs, they employ a polycarbonate substrate, a reflective layer, and a protective top layer. Sandwiched between the substrate and reflective layer, however, is a recording layer composed of an organic dye. .... Unlike regular CDs, a pre-grooved spiral track is used to guide the recording laser along the spiral track; this greatly simplifies recorder hardware design and ensures disc compatibility."
Your basic CD-R is layered like this, from top to bottom:
[optional] labelYes, it's real gold in "green" and "gold" CDs, but if you hold a CD-R up to a light source you'll notice that it's thin enough to see through (the gold layer is between 50 and 100nm thick). Something to bear in mind is that the data is closest to the label side of the CD, not the clear plastic side that the data is read from. If the CD-R doesn't have a hard top coating such as Kodak's "Infoguard", it's fairly easy to scratch the top surface and render the CD-R unusable.
[optional] scratch-resistant and/or printable coating
Reflective layer (24K gold or a silver-colored alloy)
Organic polymer dye
Polycarbonate substrate (the clear plastic part)
A pressed CD has raised and lowered areas, referred to as "lands" and "pits", respectively. A laser in the CD recorder creates marks in the disc's dye layer that have the same reflective properties. The pattern of pits and lands on the disc encodes the information and allows it to be retrieved on an audio or computer CD player. See section (2-43) for specifics.
Discs are written from the inside of the disc outward. On a CD-R you can verify this by looking at the disc after you've written to it. The spiral track makes 22,188 revolutions around the CD, with roughly 600 track revolutions per millimeter as you move outward. If you "unwound" the spiral, it would be about 3.5 miles long.
The construction of a CD-RW is different:
[optional] labelSee the net references section for pointers to more data (especially http://www.cd-info.com/). You can find some nice drawings at http://www.nswc.navy.mil/cosip/nov97/cots1197-2.shtml and http://www.pctechguide.com/09cdr-rw.htm.
[optional] scratch-resistant and/or printable coating
Upper dielectric layer
Recording layer (the part that changes form)
Lower dielectric layer
Polycarbonate substrate (the clear plastic part)
A quick summary of standards and commonly used identifiers:
See http://www.licensing.philips.com/ if you want to buy copies of the standards. They're not cheap! You can download some of them from http://www.ecma.ch/. ECMA-119 describes ISO-9660, and ECMA-130 sounds a lot like "yellow book" if you say it slowly.
For SVCD, see http://www.iki.fi/znark/video/svcd/overview/. The discs are a modified White Book format, using a 2x player and variable bit rate MPEG-2 instead of MPEG-1 at 1x like VCD.
For HDCD, see http://www.hdcd.com/. The discs are in Red Book format, but the low bit of the audio has additional information encoded in it. They sound good on a standard CD player, and better on an HDCD player.
SACD isn't really a CD format. It can have a Red Book compliant layer that is read by standard CD players, but to get the high-fidelity benefits you need a special player.
You can usually tell by looking at the packaging and/or the disc itself:
There are a few references to Compact Disc MIDI, or CD-MIDI.
See (4-46) for some comments on High Speed CD-RW.
Copy protection (sometimes erroneously referred to as "copyright protection") is a feature of a product that increases the difficulty of making an exact duplicate. The goal is not to make it impossible to copy -- generally speaking, that can't be done -- but rather to discourage "casual copying" of software and music.
The goal is *not* to conceal information from prying eyes; see section (3-19) for information on encrypting data on a CD-ROM.
A separate but related issue is "counterfeit protection", where the publisher wants to make it easy to detect mass-produced duplicates. An example of this is Microsoft's placement of holograms on the hubs of their CD-ROMs. There are full CD pressing plants dedicated to creating counterfeit software (the worst offender being mainland China), so this is a serious concern for the larger software houses.
Copy protection on CD-ROMs used to be rare, but as the popularity of CD recorders grew, so did the popularity of copy protection. A large percentage of games released in the past few years have been protected.
A more recent innovation is copy protection for audio CDs, inspired by the rise of MP3 trading over the Internet. This is more difficult to do, because the protection must allow correct behavior on a CD player but altered playback when being read by a CD-ROM drive. The best that can be accomplished is to force the user to play the music in an analog format and then re-digitize it, resulting in an imperfect reproduction.
The article at http://news.cnet.com/news/0-1005-201-7320279-0.html is a nice introduction to the issues.
Some people have questioned whether copy protection is legal. In some countries it may not be. In the USA, the law allows "fair use" of copyrighted material, but does not require that the content provider make it easy for you to do so. So while making a copy of a song for your own private use may be legal, there is nothing in the law that requires the publisher to make the material available in an unprotected format. Copy protection has been around for many years -- some of the schemes employed on the Apple II were remarkably elaborate -- and has never been challenged on legal principle.
See http://overclockers.com/tips907/ for an article about why "fair use" is a legal right rather than a constitutional right in the USA, and what that means to you. The article also has some interesting quotes from the courts regarding the DMCA and DeCSS, notably this one: "We know of no authority for the proposition that fair use, as protected by the Copyright Act, much less the Constitution, guarantees copying by the optimum method or in the identical format of the original." In other words, arguing that "fair use" means the publisher must allow you to make a perfect digital copy (as opposed to a lower-quality digital or analog copy) is without merit.
The next sections discuss data and audio individually.
There are several approaches. An article with a good overview of some popular protection technologies can be found at http://www.tomshardware.com/storage/02q2/020617/index.html. Another source is the "CD Protections" articles on http://www.cdmediaworld.com/hardware/cdrom/cd_protections.shtml.
For anyone interested in protecting their own discs: don't bother. Copy protection, on the whole, does not work. If you have a major application, such as a game or CAD package, you may want to consider one of the commercially licensed schemes listed later, or (heaven forbid) the use of a dongle. In general, though, if the disc can be read, then the contents can be copied. If you don't want somebody to make a copy of your stuff, then you'd better encrypt it (3-19).
A simple and commonly seen technique is to increase the length of several files on the CD so that they appear to be hundreds of megabytes long. This is accomplished by setting the file length in the disc image to be much larger than it really is. The file actually overlaps with many other files. So long as the application knows the true file length, the software will work fine. If the user tries to copy the files onto their hard drive, or do a file-by-file disc copy, the attempt will fail because the CD will appear to hold a few GB of data. (In practice this doesn't foil pirates, because they always do image copies. And, no, none of the standard software provides a way to create such discs.)
One possible implementation, given sufficient control over the reader and mastering software, is to write faulty data into the ECC portion of a data sector. Standard CD-ROM hardware will automatically correct the "errors", writing a different set of data onto the target disc. The reader then loads the entire sector as raw data, without doing error correction. If it can't find the original uncorrected data, it knows that it's reading a "corrected" duplicate. This is really only viable on systems like game consoles, where the drive mechanism and firmware are well defined. This can be defeated by doing "raw" reads.
A more sophisticated approach is to write special patterns of data to the disc. The stream of data that results, after EFM encoding, is difficult for some recorders to reproduce successfully, apparently because they don't choose correct values for the merging bits. This is often referred to on web sites as "writing regular EFM patterns" or "weak sectors". See section (2-43) for details on EFM.
A less sophisticated -- and no longer effective -- method is to press a silver CD with data out beyond where a 74-minute CD can write. Copying the disc used to require hard-to-find CD-R blanks, but now it's easy to use an overburned 80-minute disc (sections (3-8-1) and (3-8-3)).
The approach some PC software houses have taken is to use nonstandard gaps between audio tracks and leave index marks in unexpected places. These discs are uncopyable by most software, and it may be impossible to duplicate them on drives that don't support disc-at-once recording (see section (2-9)). With the right reader and software, though, this isn't much of a problem either.
A method that enjoyed some popularity was non-standard discs with a track shorter than 4 seconds. Most recording software, and in fact some recorders, will either refuse to copy a disc with such a track, or will attempt to do so and fail. A protected application would check for the presence and size of the track in question. Some recorders may succeed, however, so this isn't foolproof. (In one case, a recorder could write tracks that were slightly over three seconds, but refused to write tracks that were only one second. There may be a limit below which no recorder will write.) In such cases, the pirates need to remove the explicit check from the software itself.
Putting multiple data tracks interleaved with audio tracks on a CD will confuse some disc copiers. However, it's difficult to actually use the data on those additional tracks.
Sometimes the copy of a disc will have a different volume label. This usually only happens with file-by-file copies, not disc image copies, so checking the disc name is marginally useful but not very effective.
Modifying the TOC so that the disc appears to be larger than it really is will convince some copy programs that the source disc is too large.
Some of the fancier technologies use non-standard pit geometry that cause players to read the data differently on consecutive attempts. Sometimes the player sees a "1", sometimes a "0". If, when reading the track, the CD-ROM drive sees different data each time, the software knows that the disc is an original. A duplicate disc will return the same data reliably. (So too will some CD-ROM drives... this technology is not without problems.)
Some programs will examine the disc to try to determine if it's a CD-R. This doesn't work on all readers, and it's possible to disguise discs, so this isn't very effective.
CloneCD (section (6-1-49)) can copy many copy protected discs without trouble, given the right combination of reader and writer. Its main feature is "raw" reads and writes, which not all drives support.
The Laserlok system from http://www.diskxpress.com/ claims to be able to prevent unauthorized disc duplication at a low cost. It can be copied by CloneCD.
An unrelated product called LaserLock, from MLS LaserLock International (http://www.laserlock.com/) has similar features. It can be copied by CloneCD.
TTR Technology's DiscGuard (http://www.ttr.co.il/ or http://www.ttrtech.com/ claims to be able to write a signature onto pressed CDs and CD-Rs that is detectable by all CD-ROM drives but isn't reproducible without special hardware. A program could use this for copy protection by checking for the presence of the signature, and refusing to run if it's not there.
Sony DADC is promoting a simliar product called Securom. Some information is at http://www.sonydadc.com/hotnews/secu_fra.htm.
Yet another variant is C-Dilla's SafeDisc. They were bought by Macrovision (http://www.macrovision.com/). Their more recent product, SafeDisc 2, was the first to feature "weak sectors".
Yet another variant is CD-Cops from Link Data Security (http://www.linkdata.com/).
The challenge here is to create a disc that will play on a standard audio CD player but be difficult to copy or "rip" into an MP3. The techniques making headlines in mid-2001 were developed by Macrovision (2-4-3) and SunnComm (2-4-4).
The earliest form of audio CD copy protection was SCMS. This only works on recorders that support SCMS, specifically consumer-grade stand-alone audio CD recorders. "Professional" recorders, and recorders that attach to computers, do not support SCMS. See section (2-25).
Some CDs used a damaged TOC (Table of Contents -- see section (2-27)) that confused some CD-ROM drives and ripping software. More recent schemes attempt to modify the audio samples in ways that confuse CD-ROM drives into playing static. The next few sections describe these approaches in detail.
For a list of suspected copy-protected discs, and some tips on what you can do to let the industry know that the protection isn't appreciated, see http://www.fatchucks.com/corruptcds/.
Many forms of copy protection violate the CD-DA standard, and so the discs aren't allowed to use the official CD logo art. However, many CDs don't have the logo anywhere, so its absence doesn't prove anything.
A paper entitled "Evaluating New Copy-Prevention Techniques for Audio CDs" by J.A. Halderman (available only in PostScript format) can be found at http://crypto.stanford.edu/DRM2002/halderman_drm2002_pp.ps. The paper was submitted to the 2002 ACM Workshop on Digital Rights Management (http://crypto.stanford.edu/DRM2002/prog.html).
Incidentally, if you're convinced that record companies and artists are raking in huge piles of cash from every CD they sell, you might want to take a look at an Electronic Musician article that talks about where the money comes from and where it goes. See: http://industryclick.com/magazinearticle.asp?magazineid=33&releaseid=9554&magazinearticleid=132835&SiteID=15 (You may need to use IE; Netscape 4.7 for Linux couldn't view the site.)
Interesting figures: only about 16% of CDs sold make enough money for the publishers to break even. The ones that do make enough money have to pay for the rest. For the recording artists, only about 3% sell enough music to get any royalties. With figures like these, it's not surprising that the industry is taking steps to combat piracy.
For more news & commentary, see:
In the first part of the year 2000, TTR Technologies announced a product called MusicGuard (http://www.MusicGuard.com/) that claimed to prevent duplication of audio CDs. The product was withdrawn, but the technology has resurfaced in mid-2001 as a product called SafeAudio from Macrovision (http://www.macrovision.com/).
The basic idea is to create samples that sound like bursts of static, and scramble the ECC data around to make it look like an uncorrectable error. Audio CD players will interpolate the samples during playback, but CD-ROM drives doing digital audio extraction generally won't. The result is a disc that plays back correctly on a CD player, but won't "rip" or copy correctly on a CD-ROM drive.
Some relevant sites and news articles:
The digital path requires reading the "raw" audio samples off of the disc, possibly modifying the data (e.g. changing the byte ordering) into something appropriate for the sound card, and then writing them to the sound device. Until a few years ago, most CD-ROM drives did this very poorly, in part because the analog and digital data paths were logically distinct in the designers' minds. Audio CDs used the audio path, data CD-ROMs used the digital path, and while you *could* send audio over the digital path there didn't seem to be much value in doing so. (See section (2-15) for some additional notes.)
What Macrovision appears to be exploiting is the different handling of uncorrectable errors in audio samples on the digital path vs the analog path. When playing an audio CD in a CD player or CD-ROM drive, the analog path is used. This path deals with uncorrectable (E32) errors by examining the samples that come before and after the error, and interpolating between them. On a scratched-up CD, this means that, while you may not be hearing the exact samples that were originally recorded, you won't notice any glitches because they're smoothed over. This feature is definitely not something you'd want on a data CD-ROM -- interpolating pieces of your spreadsheet is not going to help you.
In most CD-ROM drives, reading an audio sector with digital audio extraction is handled the same way that reading a data sector is: uncorrectable errors are left alone. Instead of getting interpolated samples, you get to hear the original, scratched-up audio. This is why some CDs will play back just fine on your computer, but will come out all scratched up when you extract them with the same drive. The errors are there either way, but when using a desktop CD player the errors have been smoothed over by the logic in the analog output path.
Some drives may use interpolation during DAE at lower speeds. If so, it should be possible to "rip" a track from a copy-protected disc by reducing the extraction speed to 1x.
Some people have suggested that software could be used to perform the interpolation on extracted music, stripping out the bits that the music companies added in. The trouble with this approach is that, once the data has been extracted, the CIRC encoding is no longer visible. It may not be easy to tell where the glitches are. For example, it should be possible to create a low-level but rhythmic distortion that will be noticeable, annoying, and difficult to identify automatically.
(It's possible that any software specializing in defeating the copy protection would run afoul of the DMCA (Digital Millenium Copyright Act), and the authors subject to fines and criminal prosecution. Come to think of it, the preceeding discussion might be illegal. For more information about the DMCA, see http://www.eff.org/.)
How can you get a "clean" copy of a protected disc? There are four basic approaches, in order of least to most desirable:
(1) Record directly from the analog outputs of the drive, feeding the sound into a sound card or outboard A/D converter. Some fidelity will be lost when converting from digital to analog and back again, which is what the industry is counting on.
(2) It should be possible to play the disc on a CD player with an S/PDIF connector, and get error-interpolated digital output. If played into a digital sound card or a CD recorder with an S/PDIF input, it should be possible to capture an exact copy of the original. Of course, it has to be done at 1x, and the track breaks may have to be added manually, making it a potentially tedious affair. This might be avoidable on a CD-R "dubbing deck", but inexpensive models will add SCMS to the set of things to worry about. Don't forget that generation loss is possible with CDs, especially if you record from CD-Rs (due to their higher BLER rate), so copying to CD-R and then extracting from CD-R requires some care. See section (3-18).
(3) Some drives support an extension described in recent versions of the ATA/ATAPI and SCSI MMC specifications. This extension to the "READ CD" command returns a set of flags indicating which bytes in an audio block were not corrected at the C2 level (section (2-17). An audio extraction application with access to this information could do its own interpolation across errors. Some applications already make some use of this feature; see http://www.feurio.com/English/faq/faq_vocable_c2error.shtml. The "drive check" feature of cdspeed (section (6-2-11)) reports on whether or not a drive is capable of returning "C2 pointers".
(4) A CD-ROM drive with logic that interpolates uncorrectable errors during DAE would allow copying and ripping with no additional effort required.
The success or failure of audio CD copy protection hinges upon two factors: how effective is it at preventing "casual copying", and what sort of problems do the legitimate owners of audio CDs encounter when playing their discs? Macrovision claims that their "golden ear" listeners were not able to tell the difference, though the test might be biased if the folks with the shiny lobes were using high-end CD players that did an especially good job of concealing uncorrectable errors.
A legitimate technical concern is that the copy protection reduces the effectiveness of the error correction. Because some percentage of ECC is now required for proper playback on a *clean* disc, the odds of scratches and fingerprints causing audible degredation are increased. In practice, if the "static" samples are relatively few and far between, the difference would be statistically insignificant.
One last piece of advice: do not assume that any disc that doesn't extract cleanly is copy-protected. There have been many, many postings on message boards from people who think they have found a protected disc, or how some specific piece of software can defeat the protection. Start with the more common reasons: the disc is dirty, the disc was poorly made, your CD-ROM drive is not that great at audio extraction, you're using software that isn't the best. There are many reasons why ripping an audio track might fail. People have been having trouble getting clean audio for years. See section (3-3) for some advice if you're having trouble.
Certain web sites (notably cdfreaks.com) have been reporting that a replacement CDFS.VXD will fix everything. However, doing the audio extraction in a VXD instead of an EXE makes no difference. So far, none of the sites that have claimed victory list a single SafeAudio-protected disc that was copied, most likely because -- at the time this was written -- there weren't any discs known to use SafeAudio. (This phenomenon is not unheard-of; Sega's Dreamcast discs were widely reported to be copyable by a means that was quickly determined to be utterly ridiculous.) If the widely-touted CDFS.VXD is in fact a hijacked Plextor driver, then it may well use technique #3 mentioned above, but would only work on a drive that supported the extended READ CD feature.
SunnComm (http://www.sunncomm.com/) has a product called "MediaCloQ". It was used to protect the album _A Tribute to Jim Reeves_ by Charley Pride in mid-2001. The results were inconclusive: clean versions of the tracks appeared on the net, but SunnComm claimed they came from an unprotected disc released on Australia. Their plan was to alleviate "fair use" concerns by allowing users to download MP3 versions of the songs after they registered the original. Some articles:
The idea behind this protection is to make it hard for CD-ROM drives to identify the disc as being an audio CD. The disc is multisession, and uses a hacked TOC, so track rippers and disc copiers have trouble dealing with it. SunnComm hasn't publicly stated any details.
In August 2001, SunnComm announced v2.0 of their product, but didn't provide specific details.
Some personal notes on SunnComm's protection of the Charley Pride disc, including the steps I took to get a clean copy:
The packaging is labeled with the SunnComm logo, and states, "This audio CD is protected by SunnComm(tm) MediaCloQ(tm) Ver 1.0. It is designed to play in standard audio CD players only and is not intended for use in DVD players." However, my DVD player was able to play the disc after overcoming some initial confusion.
The disc itself has an unusual construction. There is a heavy band at about the point where the music stops, and thin bands between tracks. These appear to be purely decorative (and, I'm told, increasingly common on non-protected discs). Some images are available on http://www.fadden.com/cdrpics/.
A computer running Win98SE with a Plextor 40max CD-ROM drive saw the disc as having two sessions and 16 data tracks. My CD player only saw 15 audio tracks. This feature alone makes the disc difficult to rip or copy, because the software doesn't see any audio tracks, and a CD-R copy would be full of tracks that even a CD player would see as data. Another machine, with a Plextor 12/20 and a slightly different set of software, seemed to have a lot of trouble figuring out what the disc was. It eventually sorted things out, but I get the sense the disc has been tweaked in ways that confuse the drive firmware.
I tried using "Session Selector" to select the first session and then access the tracks. This resulted in a Plextor 8/20 CD recorder becoming unusable until a reboot. I'd guess the firmware got confused.
The next thing I tried was to crank up CDRWIN v3.7a (section (6-1-7)), and extract some tracks using my Plextor 12/20. No dice -- the display showed 15 unselectable tracks and 1 MODE-2 data track.
Next, I tried the "Extract Disc/Tracks/Sectors" function, selected "Extract Sectors", chose "Audio-CDDA (2352)" for the data type, and entered a nice range (0 to 300000, where each audio sector is 1/75th of a second). This choked when trying to read starting at block 173394, so I tried again stopping at 173390. This resulted in a rather large WAV file, which I opened with Cool Edit -- revealing the entire contents of the disc, plain and clear. Playback revealed no audible defects.
I believe this worked because the sector extraction function ignores track and session boundaries, and just pulls the blocks straight off. Losing the track markers is annoying, but it's easy to add them back with something like CDWave (section (6-2-16)).
(FWIW, this same approach did *not* work for the _My Private War_ disc with the damaged TOC, described in (2-4-2). It would probably not be of help with a SafeAudio disc either.)
"zEEwEE" came up with a complicated but enlightening scheme for side-stepping the protection on discs with damaged second TOCs. It has the advantage of allowing you to use standard tools, such as Exact Audio Copy ( section (6-2-12)), which keeps the track breaks and can do fancy tricks to get the best extraction quality. See http://cdprot.cjb.net/. [ I'm told the disc used as an example was actually protected with Midbar Tech's Cactus Data Shield 100, not MediaCloQ. ] The method involves making the outer rim of the disc unreadable to the CD-ROM drive. It appears you can use dry erase markers instead of adhesive stickers for the procedure, which is good since an adhesive label might peel up and damage your drive. This method, first posted in August of 2001, resulted in a flurry of media attention in May of 2002.
Midbar Tech Ltd (http://www.midbartech.com/) appears to have two different schemes under the "Cactus Data Shield" brand. (The web site shows three now: CDS100, CDS200, and CDS300.) The first uses a non-standard TOC. The position of the lead-out and the length of the last track were tweaked, resulting in a disc that appears to be only 28 seconds long. The alterations didn't confuse all CD-ROM drives, and it has been reported that some Philips CD players couldn't play the discs. BMG Entertainment reportedly tried it and abandoned it.
In late 2001, Midbar Tech announced a different approach. A US patent (http://www.delphion.com/details?&pn=US06208598__) describes the invention.
The approach appears to involve inserting frames of bogus control information into a relatively constant part of the CD audio stream. During playback, the extra frames are skipped. A disc copy or digital stream on an S/PDIF output will include the bogus frames, and when written to CD-R the extra control information won't be included. The result is bad samples that only appear in copies.
No specific disc titles have been announced, but Sony has reportedly released a few titles in eastern Europe that use this.
Some personal notes on the early version (CDS100?) of the Cactus Data Shield: I bought a copy of _My Private War_, by Phillip Boa & The Voodoo Club, from an online retailer. The disc is labeled "Kopiergeschützte CD - nicht am pc abspielbar" which translates literally to "copy-protected CD - not at the PC playable". Supposedly this is one of the BMG discs that was protected with Midbar's first product.
The Plextor Plextools utility saw it as a single-session audio CD with 13 tracks, but when I asked it to play the disc it only saw the first 28 seconds of the first track, and stopped after playing just that much. My Panasonic CD "boom box" also thought the disc was only 28 seconds long, but it happily played past that point, and would let me select any track.
The page at http://uk.eurorights.org/issues/cd/docs/natimb.shtml has an analysis of the CD _White Lilies Island_ by Natalie Imbruglia.
http://www.cdrinfo.com/Sections/Articles/Specific.asp?ArticleHeadline=Cactus%20Data%20Shield%20200&index=0 has a very thorough examination of a CDS200 disc. Recommended reading.
This was used to protect promotional copies of the Michael Jackson single "You Rock My World". See http://www.key2audio.com/ for product information.
The "Duolizer" system splits music into two pieces. The bulk of the music is on the CD, but a small but essential piece is streamed from a secure server over the Internet. The idea is to allow music publishers to distribute songs to the media and retail outlets ahead of scheduled releases. This was a response to songs appearing in MP3 form on the Internet before the CDs went into distribution.
See http://www.bayviewsystems.com/solutions/duolizer.htm for product info.
As an added bonus, because the music is streamed from a central location, it could have a digital watermark added. If (say) somebody at a radio station made an MP3 copy, it might be possible to trace the source of the MP3 file back to the source. There is nothing on the product pages to suggest that such a scheme is currently in place.
Sany has joined the growing list of companies to announce CD copy protection. It's not clear if this is their own scheme or one licensed from another company.
The disc has an embedded secure micro (like a smart card) that is activated when the laser light strikes a photodetector. The light is converted to electrical impulses, the impulses drive the chip, and if all goes well the results are presented to the drive via an embedded light-emitting diode.
Making an exact duplicate of the disc would be very difficult. It's unclear whether this technology actually makes it harder to get a working copy of the contents. The scheme seems to essentially be a combination of an "uncopyable" disc and a hardware dongle, both of which have been around for years (neither of which have brought an end to piracy).
The company's web site is http://www.doc-witness.com/.
A session is a recorded segment that may contain one or more tracks of any type. The CD recorder doesn't have to write the entire session at once -- you can write a single track, and come back later and write another -- but the session must be "closed" before a standard audio CD or CD-ROM player will be able to use it. Additional sessions can be added until the *disc* is closed or there's no space left.
Multisession writing was first used on PhotoCD discs, to allow additional pictures to be appended. Today it's most often used with "linked" multisession discs, and occasionally for CD-Extra discs. These require a bit more explanation.
When you put a data CD into your CD-ROM drive, the OS finds the last closed session on the disc and reads the directory from it. (Well, that's how it's supposed to work. Depending on your operating system and CD-ROM drive, you may get different results.) If the CD is ISO-9660 format - which it almost certainly is unless it's a Macintosh CD written in HFS - the directory entries can point at any file on the CD, no matter which session it was written in.
Most of the popular CD creation programs allow you to "link" one or more earlier sessions to the session currently being burned. This allows the files from the previous sessions to appear in the last session without taking up any additional space on the CD (except for the directory entry). You can also "remove" or "replace" files, by putting a newer version into the last session, and not including a link to the older version.
In contrast, when you put an audio CD into a typical CD player, it only looks at the first session. For this reason, multisession writes don't work for audio CDs, but as it happens this limitation can be turned into an advantage. See section (3-14) for details. This limitation does *not* mean you have to write an entire audio CD all at once; see section (2-9) for an overview of track-at-once writing.
(Some audio CD players do seem to be able to recognize all of the tracks on a multisession audio disc. Most do not. The only way to know for sure is to try and see. If you are planning to give an audio CD you create to others, it would be wise to write it in a single session.)
Note that mixing MODE-1 (CD-ROM) and MODE-2 (CD-ROM/XA) sessions on a single disc isn't allowed. You could create such a thing, but many CD-ROM drives will have a hard time recognizing it.
See also http://www.roxio.com/en/support/cdr/multisession.html, which goes into more depth.
Discs written with packets are an entirely different story. See section (6-3).
Quick recap: if you want to write some data to a CD-ROM now, and some more later, you write a single data track in multiple sessions (or with packet writing). If you want to write some audio tracks to a CD now, and some more later, you write multiple audio tracks in a single session.
There are eight subcode channels (P,Q,R,S,T,U,V,W). The exact method of encoding is discussed in section (2-43), but it's really only important to note the data is distributed uniformly across the entire CD, and each channel can hold a total of about 4MB.
The P subcode channel identifies the start of a track, but is usually ignored in favor of the Q channel.
The Q subcode channel includes useful information, which can be read and written on many recorders. The user data area contains three types of subcode-Q data: position information, media catalog number (MCN), and ISRC code. Other forms are found in the lead-in, and are used to enable multisession and describe the disc TOC (table of contents).
The position information is used by audio CD players to display the current time, and has track/index information. This can be controlled when doing Disc-At-Once recording.
The ISRC (International Standard Recording Code) is used by the recording industry. It states the country of origin, owner, year of issue, and serial number of tracks, and may be different for each track. It's optional; many CDs don't use this. The media catalog number is similar, but is constant per disc. Note these are different from the UPC codes.
See http://www.ee.washington.edu/conselec/CE/reports/Group.1/matt_page_individual/subcode.html for some details on P and Q.
The R-W subcode channels are used for text and graphics in certain applications, such as CD+G (CD w/graphics, supported by SegaCD among others). A new use has been devised by Philips, called ITTS. It enables properly equipped players to display text and graphics on Red Book audio discs. The most recent result of this technology is "CD-Text", which provides a way to embed disc and track data on a standard audio CD.
Not many publishers use them, and not all devices can read all of the fields.
Programs that identify audio CDs automatically don't rely on an embedded serial number. Instead, they compute an ID based on the quantity and positions of the audio tracks, measured down to 1/75th of a second. http://www.cddb.com/ has a collection of CD information.
It depends on how much data you're going to burn, and how fast your drive is. Burning 650MB of data takes about 74 minutes at 1x, 37 minutes at 2x, and 19 minutes at 4x, but you have to add a minute or two for "finalizing" the disc. Remember that single speed for CD-ROMs is 150KB/sec, double speed is 300KB/sec, and so on.
If you have half the data, it will finish in (about) half the time. If you record the same thing twice as fast, it will finish in (about) half the time.
Most CD recording speeds are linear, i.e. recording at 12x is twice as fast as recording at 6x. If the drive uses a PCAV mechanism (see section (5-22)) the speed varies depending on which part of the disc you're recording. If a "20x" drive uses PCAV to get 12x at the start of the disc and 20x near the outside, you know that burning 60 minutes of audio will take somewhere between about 5 minutes and about 3 minutes.
There are two basic ways of writing to a CD-R. Disc-at-once (DAO) writes the entire CD in one pass, possibly writing multiple tracks. The entire burn must complete without interruption, and no further information may be added.
Track-at-once (TAO) allows the writes to be done in multiple passes. There is a minimum track length of 300 blocks (600K for typical data CDs), and a maximum of 99 tracks per disc, as well as a slight additional overhead associated with stopping and restarting the laser.
Because the laser is turned off and on for every track, the recorder leaves a couple of blocks between tracks, called run-out and run-in blocks. If done correctly, the blocks will be silent and usually unnoticeable. CDs with tracks that run together will have a barely noticeable "hiccup". Some combinations of software and hardware may leave junk in the gap, resulting in a slight but annoying click between tracks. Some drives and/or software packages may not let you control the size of the gap between audio tracks when recording in track-at-once mode, leaving you with 2-second gaps even if the original didn't have them.
Many recorders, starting with the venerable Philips CDD2000, allow "session-at-once" (SAO) recording. This gives you disc-at-once control over the gaps between tracks, but allows you to leave the disc open. This can be handy when writing CD Extra discs (see section (3-14)).
There are some cases where disc-at-once recording is required. For example, it may be difficult or impossible to make identical backup copies of some kinds of discs without using disc-at-once mode (e.g. copy-protected PC games). Also, some CD mastering plants may not accept discs recorded in track-at-once mode, because the gaps between tracks will show up as uncorrectable errors.
The bottom line is that disc-at-once recording gives you more control over disc creation, especially for audio CDs, but isn't always appropriate or necessary. It's a good idea to get a recorder that supports both disc-at-once and track-at-once recording.
For further commentary, see http://www.yangkun.com/CDR/redbook.shtml.
Many CD-R creation packages will give you a choice between creating a complete image of the CD on disk and doing what's called "on-the-fly" writing. Each method has its advantages.
Disc image files are sometimes called virtual CDs or VCDs (not to be confused with VideoCD). These are complete copies of the data as it will appear on the CD, and so require that you have enough hard drive space to hold the complete CD. This could be as much as 650MB for CD-ROM or 747MB for an audio disc when using 74-minute blanks. If you have both audio and data tracks on your CD, there would be an ISO-9660 filesystem image for the data track and one or more 16-bit 44.1KHz stereo sound images for the audio tracks.
(On the Mac, you might instead use an HFS filesystem for the data track. You can create the image with Mac CD recording software, or create it as a DiskCopy image file and then burn the data fork under a different OS.)
On-the-fly recording often uses a "virtual image", in which the complete set of files is examined and laid out, but only the file characteristics are stored, not the data. The contents of the files are read while the CD is being written. This method requires less available hard drive space and may save time, but increases the risk of buffer underruns (see (4-1)). With most software this also gives greater flexibility, since it's easier to add, remove, and shuffle files in a virtual image than a physical one.
A CD created from an image file would be identical to one created with on-the-fly recording, assuming that both would put the same files in the same places. The choice of which to use depends on user preference and hardware capability.
There are subcode flags in the Q channel for each track:
CD-RW is short for CD-Rewritable. It used to be called CD-Erasable (CD-E), but some marketing folks changed it so it wouldn't sound like your important data gets erased on a whim. The difference between CD-RW and CD-R is that CD-RW discs can be erased and rewritten, while CD-R discs are write-once. Other than that, they are used just like CD-R discs.
Let me emphasize that: they are used just like CD-R discs. You can use packet writing on both CD-R and CD-RW, and you can use disc-at-once audio recording on both CD-R and CD-RW. Some software may handle CD-RW in a slightly different way, because you can do things like erase individual files, but the recorder technology is nearly identical.
CD-RW drives use phase-change technology. Instead of creating "bubbles" and deformations in the recording dye layer, the state of material in the recording layer changes from crystalline to amorphous form. The different states have different refractive indicies, and so can be optically distinguished.
These discs are not writable by standard CD-R drives, nor readable by most older CD readers (the reflectivity of CD-RW is far below CD and CD-R, so an Automatic Gain Control circuit is needed to compensate). Most new CD-ROM drives do support CD-RW media, but not all them will read CD-RW discs at full speed.
A few older audio CD players and many new ones can handle CD-RW discs, but many can't. If you want to create audio CDs on CD-RW media, make sure that your player can handle them.
All CD-RW recorders can write to CD-R media, so the only reason not to buy a CD-RW recorder is price. Some Internet sites like to put the devices in completely separate categories, calling them "CD recorders" and "CD ReWriters", but the differences between them don't really merit such a distinction. Think of a "CD ReWriter" as a CD recorder that can also make use of CD-RW media.
Oddly enough, it may be easier for a DVD drive to read CD-RW discs than CD-R discs, because of the way the media is constructed.
CD-RW media is more expensive than CD-R, but recent price reductions have narrowed the gap considerably. There is a limit to the number of times an area of the disc can be rewritten, but that number is relatively high (the Orange Book requires 1000, but some manufacturers have claimed as much as 100,000). Of course, this is under laboratory conditions. If you don't handle the disc carefully, you will add scratches, dirt, fingerprints, and other obstacles that make the disc harder for the drive to read.
It appears that CD-RW discs have speed ratings encoded on them, so discs that are only certified for 2x recording can't be written to at 4x (or, for that matter, 1x). To make things more complicated, different media is required for high-speed CD-RW drives (those that exceed 4x). See http://www.emediapro.net/EM2000/writer11.html for an explanation.
If you're trying to decide if you want a drive that supports CD-RW, see section (5-16).
The only discs that a DVD player is guaranteed to read are DVD discs. Support for CD-ROM, CD-R, and CD-RW may be included, but is by no means guaranteed.
CD-R was designed to be read by an infrared 780nm laser. DVD uses a visible red 635nm or 650nm laser, which aren't reflected sufficiently by the organic dye polymers used in CD-R media. As a result, many DVD players can't read CD-R media. Some DVD players come with two lasers so that they can read CD-R. For a technical discussion, see http://www2.osta.org/osta/html/cddvd/intro.html and http://www.emedialive.com/EM1998/bennett3.html.
CD-RW discs have a different formulation, and may work even on players that can't handle CD-R media. If CD-R media doesn't work, try copying the disc to CD-RW instead (assuming your recorder supports CD-RW).
Some DVD-ROM drives may be unable to read multisession discs. In general, though, DVD-ROM drives (as opposed to DVD players) are able to read CD-R media.
If the box doesn't say that something is supported, assume that the feature isn't. Look for the MultiRead or MultiPlay logos, which indicate that the DVD player or DVD-ROM drive can read CD-R and CD-RW.
See also "Is XXX compatible with DVD" in the DVD FAQ:
Perhaps, but it's best if you can get a "combo" drive that records on CDs as well.
CDs are starting to pass the venerable 3.5" floppy disk as the most universal physical media. If you want to be able to exchange music or data with someone else, CD and CD-ROM are your best bet. DVD-ROM drives and DVD players haven't been as successful as some in the industry had hoped. Near the end of 2000, one of the major computer sellers was offering an "upgrade" on their systems from DVD-ROM drives to CD recorders.
DVD-R recorders and media are still fairly expensive compared to CD-R, though they're finally down to consumer levels. An example: http://www.electroweb.com/product/hard.htm was, as of early February '98, selling a Pioneer CDVR-S101 DVD-Recordable Drive for US$18K. In June '99, the same site had a Pioneer CDVR-S201 for US$5100. In October 2001 the Pioneer DVR-A03PK was on sale for $699, and the price of media had fallen from $50 to $15 per disc.
In mid-2001 Apple started selling a drive with high-end Macintoshes that wrote to both CD-R and DVD-R. If you can afford it, being able to write either format is valuable.
Writers for related formats like DVD-RAM and DVD+RW are available for less, but aren't widely compatible with current DVD players. HP and several other companies are promoting the DVD+RW format, which is compatible with DVD players and is rewritable. See http://www.dvdplusrw.org/.
As mentioned in section (0-2), this FAQ will not be expanding to cover DVD recorders. See http://www.dvddemystified.com/dvdfaq.html instead.
The first thing to know is that there are two kinds of jitter that relate to audio CDs. The usual meaning of "jitter" refers to a time-base error when digital samples are converted back to an analog signal; see http://www.digido.com/jitteressay.html for a discussion. The other form of "jitter" is used in the context of digital audio extraction from CDs. This kind of "jitter" causes extracted audio samples to be doubled-up or skipped entirely. (Some people will correctly point out that the latter usage is an abuse of the term "jitter", but we seem to be stuck with it.)
"Jitter correction", in both senses of the word, is the process of compensating for jitter and restoring the audio to its intended form. This section is concerned with the (incorrect use of) "jitter" in the context of digital audio extraction.
The problem occurs because the Philips CD specification doesn't require block-accurate addressing. While the audio data is being fed into a buffer (a FIFO whose high- and low-water marks control the spindle speed), the address information for audio blocks is pulled out of the subcode channel and fed into a different part of the controller. Because the data and address information are disconnected, the CD player is unable to identify the exact start of each block. The inaccuracy is small, but if the system doing the extraction has to stop, write data to disk, and then go back to where it left off, it won't be able to seek to the exact same position. As a result, the extraction process will restart a few samples early or late, resulting in doubled or omitted samples. These glitches often sound like tiny repeating clicks during playback.
On a CD-ROM, the blocks have a 12-byte sync pattern in the header, as well as a copy of the block's address. It's possible to identify the start of a block and get the block's address by watching the data FIFO alone. This is why it's so much easier to pull single blocks off of a CD-ROM.
With most CD-ROM drives that support digital audio extraction, you can get jitter-free audio by using a program that extracts the entire track all at once. The problem with this method is that if the hard drive being written to can't keep up, some of the samples will be dropped. (This is similar to a CD-R buffer underrun, but since the output buffer used during DAE is much smaller than a CD-R's input buffer, the problem is magnified.)
Most newer drives (as well as nearly every model Plextor ever made) are based on an architecture that enables them to accurately detect the start of a block.
An approach that has produced good results is to do jitter correction in software. This involves performing overlapping reads, and then sliding the data around to find overlaps at the edges. Most DAE programs will perform jitter correction.
Some information about "the goode olde days" can be found in Robert Starrett's "The History of CD-R" article, currently available from http://www.roxio.com/en/support/cdr/historycdr.html.
The first CD player was available in Japanese stores on October 1, 1982. CD-Recordable technology wasn't introduced until 1988. For a timeline, see http://www.oneoffcd.com/info/historycd.cfm.
Back in the late 1980s, CD recorders cost thousands of dollars, and were part of systems the size of a washing machine. Disks cost US$100.00 each.
Things started to get better in 1995, when Yamaha released the CDR100 (the first 4x recorder) for a mere US$5000.00. In September of 1995, HP released the 4020i (a 2x recorder based on the Philips CDD2000) for just under US$1000.00. Media was down to about US$8.00, though 80-minute discs were extremely rare and expensive (US$40.00 each, if you could find them at all).
Actually, they do. It is true that audio CDs use all 2352 bytes per block for sound samples, while CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data. The error correction that keeps your CDs sounding the way they're supposed to, even when scratched or dirty, is applied at a lower level. So while there isn't as much protection on an audio CD as there is on a CD-ROM, there's still enough to provide perfect or near-perfect sound quality under adverse conditions.
All of the data written to a CD uses CIRC (Cross-Interleaved Reed-Solomon Code) encoding. Every CD has two layers of error correction, called C1 and C2. C1 corrects bit errors at the lowest level, C2 applies to bytes in a frame (24 bytes per frame, 98 frames per sector). In addition, the data is interleaved and spread over a large arc. (This is why you should always clean CDs from the center out, not in a circular motion. A circular scratch causes multiple errors within a frame, while a radial scratch distributes the errors across multiple frames.)
If there are too many errors, the CD player will interpolate samples to get a reasonable value. This way you don't get nasty clicks and pops in your music, even if the CD is dirty and the errors are uncorrectable. Interpolating adjacent data bytes on a CD-ROM wouldn't work very well, so the data is returned without the interpolation. The second level of ECC and EDC (Error Detection Codes) works to make sure your CD-ROM stays readable with even more errors.
It should be noted that not all CD players are created equal. There are different strategies for decoding CIRC, some better than others.
Some CD-ROM drives can report the number of uncorrected C2 errors back to the application. This allows an audio extraction application to guarantee that the extracted audio matches the original. The Plextor UltraPlex 40 is one such drive.
See http://www.cdpage.com/dstuff/BobDana296.html for an overview of error correction from the perspective of media testing. If you really want to get into the gory technical details, try http://www.ee.washington.edu/conselec/CE/kuhn/cdmulti/95x7/iec908.htm.
MiniDiscs, or MDs, are small (64mm) discs that hold about 140MB of data or 160MB of audio. By using sophisticated compression techniques they are able to compress audio by a 5:1 ratio, allowing a capacity of 74 minutes with little or no audible difference in quality. As with CD recorders, there are MD recorders that connect to your computer and MD recorders that connect to your stereo.
There are stamped MDs that are similar to CDs in construction, and rewritable MDs that use magneto-optical technology. Audio MD recorders are generally more convenient than stand-alone audio CD recorders, because the playback mechanism allows a more flexible layout of audio data, so it's possible to delete a track from the middle of the MD and then write a longer one that is recorded in different places across the disc. The current generation of MD technology is unlikely to replace CD-R or DAT, however, because the lossy compression employed is disdained by audio purists. MD is more often positioned as a replacement for analog cassette tape, which it matches in portability and recordability, and surpasses in durability and its ability to perform random accesses.
Computer-based MD recorders can write data, but may not be able to record audio. Check the specifications carefully.
A wealth of information is available from http://www.minidisc.org/. If you want to transfer CD to MD or MD to CD-R, check there for more information. (It used to be item #37 in the FAQ, but doesn't seem to be now.)
A disc that you can add data to is "open". All data is written into the current session. When you have finished writing, you close the session. If you want to make a multisession disc, you open a new session at the same time. If you don't open a new session then, you can't open one later, which means that it's impossible to add more data to the CD-R. The entire disc is considered "closed".
The process of changing a session from "open" to "closed" is called "finalizing", "fixating", or just plain "closing" the session. When you close the last session, you have finalized, fixated, or closed the disc.
A single-session disc has three basic regions: the lead-in, which has the Table of Contents (or TOC); the program area, with the data and/or audio tracks; and the lead-out, which is filled with zeroes and provides padding at the end of the disc. An "open" single-session disc doesn't yet have the lead-in or lead-out written.
If you write data to a disc and leave the session open, the TOC -- which tells the CD player or CD-ROM drive where the tracks are -- is written into a separate area called the Program Memory Area, or PMA. CD recorders are the only devices that know to look at the PMA, which is why you can't see data in an open session on a standard playback device. CD players won't find any audio tracks, and CD-ROM drives won't see a data track. When the session is finalized, the TOC is written in the lead-in area, enabling other devices to recognize the disc.
(Something to try: write an audio track to a blank CD, and leave the session open. Put the disc in a CD player. Some players will deny the existence of the disc, some will spin the disc up to an incredible speed and won't even brake the spindle when you eject the disc, others will perform equally random acts. The TOC is important!)
If you close the current session and open a new one, the lead-in and lead-out of the current session will be written. A TOC will be written in the current lead-in that points to the eventual TOC of the next session. This process is repeated for every closed session, resulting in a chain of links from one lead-in area to the next. Typical audio CD players don't know about chasing TOC links, so they can only see tracks in the first session. Your CD-ROM drive, unless it's broken or fairly prehistoric, will know about multisession discs and will happily return the first session, last session, or one somewhere in between, depending on what the OS tells it and what it is capable of.
Some CD-ROM drives, notably certain early NEC models, are finicky about open sessions, and will gag when they try to read the lead-in from a still-open session. They follow the chain of links in the lead-ins of each session, but when they get to the last, they can't find a valid TOC and become confused. Even though these drives support multi-session, they require that the last session be closed before they will read the disc successfully. Fortunately, most drives don't behave this way.
If you use disc-at-once (DAO) recording, the lead-in is written at the very start of the process, because the contents of the TOC are known ahead of time. With most recorders there is no way to specify that more than one session should be created in DAO mode, so creating a multisession disc with DAO recording isn't generally possible. Such discs must be created with track-at-once (TAO) or session-at-once (SAO) recording.
If you're using certain versions of Windows, the Auto Insert Notification feature will "discover" the CD-R as soon as the TOC is written. This can cause the write process to fail, which is why Windows software automatically enables and disables AIN as needed. Otherwise, if recording in track-at-once mode, it will fail during finalization; in disc-at-once mode, it will fail near the beginning of the write process. In both cases, test writes will succeed, because the TOC doesn't get written during a test pass.
Packet-written discs follow the same rules with regard to open and closed sessions, which is why they have to be finalized before they can be read on a CD-ROM drive. The "Packet Writing - Intermediate" document in the primer at http://www.mrichter.com/cdr/primer/primer.htm goes into a little more detail on this subject. (Some people like to refer to packet writing as "PAO", for packet-at-once.)
There are gory details beyond what is written here. For example, the lead-in on a CD-R actually has a pre-recorded TOC that specifies physical parameters of the recording layer, such as required laser recording power, and information about the disc, like how many blocks can be written (the "ATIP" discussed in section (2-38)). You don't usually need to worry about such things though.
There is absolutely nothing special about the audio data encoded on a CD. The only difference between a "raw" 44.1KHz 16-bit stereo WAV file and CD audio is the byte ordering.
It isn't necessary to convert a WAV or AIFF file to a special format to write to a CD, unless you're using a format that your recording software doesn't recognize. For example, some software won't record from MP3 files, or from WAV files that aren't at the correct sampling rate. Similarly, you don't have to do anything special to audio extracted from a CD. It's already in a format that just about anything can understand.
Just put your audio into the correct format -- uncompressed 44.1KHz, 16-bit, stereo, PCM -- and the software you use to write CDs will do the rest. All of the fancy error correction and track indexing stuff happens at a lower level.
Don't get confused by programs (such as Win95 Explorer) that show ".CDA" files. This is just a convenient way to display the audio tracks, not a file format unto itself. See section (2-36).
The MultiRead logo indicates that a CD or DVD drive can read all existing CD formats, including CD-ROM, CD-DA, CD-R and CD-RW. See the description at http://www.osta.org/specs/multiread.htm The presence of this logo on a CD-ROM drive does *not* mean that the drive can read DVD.
MultiPlay does essentially the same thing, but is meant for consumer CD and DVD players. See http://www.osta.org/specs/multiplay.htm.
That depends on what was being recorded, how it was being recorded, and how far along in the process things were.
If it failed while writing the lead-in, before any data was written, the disc probably isn't usable. Some drives, notably certain Sony models, have a "repair disc" option that forcefully closes the current session. This would allow you to add extra data in a second session on the disc, but anything written in the first session will be unavailable.
Failures when finalizing the disc may be correctable. Sometimes the TOC gets written before the failure, and the disc can be used as-is. Sometimes you can use a "finalize disc" option from a program menu that will do the trick. Other times the recorder will refuse to deal with a partially-finalized disc, and you're stuck.
Failures in the middle of writing result in a CD-ROM that probably isn't worth trusting. Some of the data will be there, some won't. The directory for the disc may show more files than are actually present, and you won't know which are actually there until you try to read them.
Audio CDs recorded in disc-at-once mode are a special case. Because the TOC is written up front, the disc is readable in a standard CD player even if the write process doesn't finish. You will be able to play the tracks up to the point where the recording failed.
If you were using a packet writing program like DirectCD, the experiences of people on Usenet suggest that you are either 100% okay or 100% screwed. The ScanDisk utility included with DirectCD 2.5 may help though.
This phenomenon is familiar to users who have attempted to extract digital audio from a CD-R. Very often the result of copying an audio CD is an exact copy of the original audio data, but with a few hundred zero bytes inserted at the front (and a corresponding number lost off the end). Since this represents the addition of perhaps 1/100th of a second of silence at the start of the disc, it's not really noticeable.
The actual number of bytes inserted may very slightly from disc to disc, but a given recorder usually inserts about the same number. It's usually less than one sector (2352 bytes).
According to a message from a Yamaha engineer, the cause of the problem is the lack of synchronization between the audio data and the subcode channels, much like the "jitter" described in section (2-15). The same data flow problems that make it hard to find the start of a block when reading also make it hard to write the data and identifying information in sync. According to the engineer, no changes to the firmware or drive electronics can fix the problem.
Making copies of copies of audio CDs would result in a progressively larger gap, but it's likely to be unnoticeable even after several generations.
You can have up to 99 tracks. Because the track number is stored as a two-digit decimal number starting with "01" (BCD encoded, in case you were wondering), it's not possible to exceed this.
Tracks must be at least 4 seconds long, according to the standard. In practice, CD recorders have different notions of how short a track can be, but most recorders will refuse to write a track shorter than one second.
The maximum number of files depends on the filesystem you're using. For ISO-9660, you can (in theory) have as many as you want. In practice, DOS or Windows will treat the disc internally as a FAT16 filesystem, so you are limited to about 65,000 files if you want broad compatibility.
SCMS is the Serial Copy Management System. The goal is to allow consumers to make a copy of an original, but not a copy of a copy. Analog recording media, such as audio cassettes and VHS video tape, degrades rather quickly with each successive copy. Digital media doesn't suffer from the same degree of generation loss, so the recording industry added a feature that has the same net effect.
SCMS will affect you if you use consumer-grade audio equipment. Professional-grade equipment and recorders that connect to your computer aren't restricted. See section (5-12) for more about the differences between these types of devices.
The system works by encoding whether or not the material is protected, and whether or not the disc is an original. The encoding is done with a single bit that is either on, off, or alternating on/off every five frames. The value is handled as follows:
If you're using a consumer audio CD recorder, SCMS will prevent you from making copies of copies of protected material. It will not prevent you from making a copy of an original disc you have purchased, and it won't stop you from copying unprotected discs.
In general, no, but it appears that some of the newer consumer audio CD recorders write one. The Recorder Unique Identifier (RID) is a 97-bit code recorded every 100 sectors. It is composed of a brand name identifier, a type number, and a drive serial number. Recorders such as the Philips CDR870 write the RID to discourage distribution of copyrighted material.
Windows will show something like "Volume Serial Number is 4365-0FED". There does not appear to be any way to control this. Some have suggested that the serial number is generated based on data found on the disc, similar to the way that audio CDs can (mostly) be uniquely identified by the number and durations of the tracks.
On floppy disks and hard drives, the "serial number" is generated based on the date and time when the disk is formatted. The four bytes are:
The TOC (Table Of Contents) identifies the start position and length of the tracks on a disc. The TOC is present on all CDs. If it weren't, the disc would be unreadable on a CD player or CD-ROM drive. CD recorders write the TOC as part of "finalizing the disc. (Section (2-19) has some more details about finalizing discs.)
A "directory" is a list of files. If you're a Mac user, you're probably used to the term "folder". It's part of a filesystem, such as the ISO-9660 or HFS filesystem present on most CD-ROMs. Audio tracks don't have files, so they don't have directories either.
There's nothing stopping you from writing a FAT16 or Linux ext2 filesystem directly onto a CD-ROM. Whether or not you can read such a disc is a different matter. (The Linux "mount" command should allow you to mount just about anything read-only, but Windows may not be so willing.) The CD specification defines the TOC, and there are well-defined standards for certain filesystems, but [AFAIK] nothing in the CD spec requires that you fill a data track with a certain kind of data.
In common use, an "ISO" is a file that contains the complete image of a disc. Such files are often used when transferring CD-ROM images over the Internet. Depending on who you're talking to, "ISO" may refer to all disc image files or only certain kinds.
Going by the more restrictive definition, an "ISO" is created by copying an entire disc, from sector 0 to the end, into a file. Because the image file contains "cooked" 2048-byte sectors and nothing else, it isn't possible to store anything but a single data track in this fashion. Audio tracks, mixed-mode discs, CD+G, multisession, and other fancy formats can't be represented.
To work around this deficiency, software companies developed their own formats that *could* store diverse formats. Corel developed CIF, which is still in use by Roxio's Easy CD Creator. (What does CIF mean? Nobody knows, though "Corel Image Format" is as good a definition as any.) Jeff Arnold's CDRWIN created them as "BIN" files, with a separate "cue sheet" that described the contents. You can unpack a BIN/CUE combo with "binchunker", which is now integrated into Fireburner (section (6-1-50)).
A ".DAT" file could be most anything, but usually it's a video file pulled off of a VideoCD. A program at http://www.vcdgear.com/ can convert .DAT to .MPG, and recording programs like Nero can record them directly.
A ".ISO" file that contains an image of an ISO-9660 filesystem can be manipulated in a number of ways: it can be written to a CD-ROM; mounted as a device with the Linux "loopback" filesystem (e.g. "mount ./cdimg.iso /mnt/test -t iso9660 -o loop"); copied to a hard drive partition and mounted under UNIX; or viewed with WinImage (section (6-2-2)). There is no guarantee, however, that a ".ISO" file contains ISO-9660 filesystem data. And it is quite common to hear people refer to things as "ISO" which aren't.
A ".SUB" file appears to contain subchannel data. Some programs pass these around in addition to one of the above formats.
We now have many different file extensions, including ISO, BIN, IMG, CIF, FCD, NRG, GCD, PO1, C2D, CUE, CIF, CD, and GI. Smart Projects' IsoBuster, from http://www.isobuster.com/, can open and manipulate just about any disc image format.
(The rest of this section is a philosophical rant, and can safely be skipped. This is intended to be more illustrative than factual, and any relation to actual events is strictly coincidental.)
The term "ISO" is ostensibly an abbreviation of "ISO-9660 disc image", which is itself somewhat suspect. ISO-9660 is a standard that defines the filesystem most often used on CD-ROM. It does not define a disc image format. "ISO-9660 filesystem image" would be more appropriate.
When you capture or generate a CD-ROM image, you have to call it something. When a CD-ROM was generated from a collection of files into an ISO-9660 filesystem image, it was written into a file with an extension of ".ISO". This image file could then be written to a CD-ROM. As it happens, the generated image files were no different in structure from the images that could be extracted from other CD-ROMs, so to keep things simple the extracted disc images were also called ".ISO".
(Some programs used the more appropriate ".IMG", but unfortunately that was less common.)
This meant that, whether you extracted a data track from a disc written with the HFS filesystem or the ISO-9660 filesystem, it was labeled ".ISO". This makes as much sense as formatting a 1.4MB PC floppy for HFS, creating an image, and calling it a "FAT12 disk image" because such floppies are usually formatted with FAT. It didn't really matter though, because no matter what was in the file, the software used the same procedure to write it to CD-R.
As a result of this filename extension convention, any file that contained a sector-by-sector CD-ROM image was referred to as an "ISO file". When CD recorders hit The Big Time and many people started swapping image files around, the newcomers didn't know that there was a distinction between one type of disc image and another, and started referring to *any* sort of disc image as an "ISO".
These days it's not altogether uncommon to see messages about "making an ISO" of an audio CD, which makes no sense at all.
The general belief is that it was chosen because the CD designers wanted to have a format that could hold Beethoven's ninth symphony. They were trying to figure out what dimensions to use, and the length of certain performances settled it.
There are several different versions of the story. Some say a Polygram (then part of Philips) artist named Herbert von Karajan wanted his favorite piece to fit on one disc. Another claims the wife of the Sony chairman wanted it to hold her favorite symphony. An interview in the July 1992 issue of _CD-ROM Professional_ reports a Mr. Oga at Sony made the defining request. (This is almost certainly Norio Ohga, who became President and COO of Sony in 1982 and has been a high-level executive ever since.)
The "urban legends" web site has some interesting articles for anyone wishing to puruse the matter further. The relationship of Beethoven's ninth to the length is noted "believed true" in the alt.folklore.urban FAQ listing, but no particular variant is endorsed.
http://www.urbanlegends.com/misc/cd/cd_length_skeptical.html http://www.urbanlegends.com/misc/cd/cd_length_karajan.html http://www.urbanlegends.com/misc/cd/cd_length_origin.html
Searching the net will reveal any number of "very reliable sources" with sundry variations on the theme.
You haven't closed the session yet. The lead-in area, which includes the TOC (section (2-27)), isn't written until the session is closed. A space is left for it that is large enough to see. Read section (2-19) for more details on what happens when you close a disc.
You will see the narrow unwritten strip if you:
If you use disc-at-once recording, the lead-in area is written right away, so after a failure you won't see the gap.
BURN-Proof (or BurnProof) is an unfortunate abbreviation of "Buffer-Under-RuN Proof". The technology allows you to avoid buffer underruns by suspending and restarting the write process when the recorder's buffer is about to empty. (See section (4-1) if you're not familiar with buffer underruns.)
Ideally, the results of interrupted and uninterrupted writes would be identical. In practice, there may be a small glitch at the point where writing was suspended. Sanyo recommends 4X or higher speed CD-ROM drives and audio equipment made in 1995 or later for playback.
The general concensus is that these technologies are effective and do not result in noticeable glitches.
There are several different, competing technologies. Here's a sample of what's out there (note that many of the names are trademarked):
Nearly all CD recorders announced in or after 2001 featured some variation of buffer underrun protection.
Some related technologies:
There appear to be three kinds of DVD players:
If playing CD-R discs in your DVD player is important, make sure the player can handle them before you buy a player. See section (2-13).
It's a little unclear what the player is doing to damage the CD-R media. The playback laser would have to be operated at a wavelength and intensity that caused a change in the recording dye layer.
There are no known instances of DVD-ROM drives that damage discs.
Many of the "big name" media manufacturers don't actually make their own media. Instead, they buy from other manufacturers and stamp their logo on the discs. Generally speaking, this isn't a bad thing, because the discs were certified good enough that the Big Brand was willing to put the company name behind the product.
If you have a picky recorder or player, though, it helps to be able to try several different pieces of media. If you buy several different brands, and they're all coming from the same manufacturer, chances are they'll all behave the same way, and your time and money will be wasted.
So... how do you tell who really made a piece of media? The short answer is: you don't.
It's tempting to believe that CD-R media identifier applications (e.g. section (6-2-9)) will give you the answer you need. Unfortunately, the data you get is unreliable at best. Charles Palmer, from cd-recordable.com, had this to say about the manufacturer identification:
"Two components that many users of these programs always take as gospel are Media Manufacturer and Dye Data. These two readings are next to worthless.The only reliable piece of information in the "ATIP" region is the disc length. See section (2-38) for further remarks.
The reason for this is that many CD-R manufacturers (like CD- Recordable.com) purchase their stampers (the nickel die that all CD-R substrates are molded from) from 3rd party sources. These 3rd party sources (either other disc manufacturers, or mastering houses) encode the data that these 'Identification' programs read, at the time that the original glass master is encoded. The 'Manufacturer' information that is encoded is usually the name of the company that made the master. Since stampers made from that master will be sold to disc manufacturers the world over, all of discs that those manufacturers produce from those stampers will contain the same 'Manufacturer' information. Information which is obviously quite erroneous and irrelevant. Very seldom will the 'manufacturer' information encoded on a CD-R actually tell you anything other than who made the original master. [...]
The second piece of data (the dye type) is also dubious. Because most master/stamper configurations are designed to be matched to specific dye types (Phthalocyanine, Cyanine, Azo, Etc), the 'Dye' information that is encoded when the master is produced indicates the type of dye that the master was designed for. This of course, does not assure that the manufacturer that buys and uses this stamper will be using it with the dye that it has been designed for. It is quite possible that a stamper/dye combination is used by a CD-R manufacturer that contradicts the 'dye' information encoded on the master. Therefore that information becomes as potentially misleading as the 'Manufacturer' data discussed earlier."
Yes. CDs encoded with DTS (Digital Theater Sound) follow the Red Book standard for the most part. The chief difference is that the audio is encoded with DTS rather than 44.1KHz 16-bit stereo PCM. If you put one into an audio CD player, it will recognize the tracks and try to play them, resulting in a hissing noise.
You can copy DTS CDs the way you would any other audio CD. Attempting to convert them to MP3 is a bad idea though -- they're already in a compressed format.
A common way to play DTS-encoded CDs is with a DVD player connected to a DTS-capable receiver. The DVD player passes multichannel audio to the receiver over an S/PDIF connection. Many DTS CDs are encoded in 5.1 surround sound, which is kinda neat.
The "Red Book" specification for audio CDs chose 44100 samples per second, where each sample is 16-bit stereo PCM. PCM is a fine choice for encoding audio, stereo is widely recognized and supported, and it's very easy to manipulate data in 16-bit quantities with existing hardware and software.
Why 44100? Why not make it a round decimal value like 44000, or a round binary quantity like 44032? Why not 32KHz or 48KHz?
In general, the human ear can hear tones out to about 20KHz. According to a smart fellow named Nyquist, you have to sample at twice that rate. Because of imperfections in filtering, you actually want to be a little above 40KHz.
According to John Watkinson's _The Art of Digital Audio_, 2nd edition, page 104, the choice of frequency is an artifact of the equipment used during early digital audio research. Storing digital audio on a hard drive was impractical, because the capacity needed for significant amounts of 1 Mbps audio was expensive. Instead, they used video recorders, storing samples as black and white levels. If you take the number of 16-bit stereo samples you can get on a line, and multiply it by the number of recorded lines in a field and the number of fields per second, you get the sampling rate. It turned out that both NTSC and PAL formats (the video standards used in US/Japan and Europe, respectively) could handle a rate of 44100 samples per second. This rate was carried over into the definition of the compact disc.
The sampling rate for "professional" audio, 48KHz, was chosen because it's an easy multiple of frequencies used for other common formats, e.g. 8KHz for telephones. It also happens to be fairly difficult to do a good conversion from 48KHz to 44.1KHz, which makes it harder to, say, copy an audio CD with a "consumer" DAT deck. (Well, okay, some consumer DAT decks can do 44.1KHz now, but initially only "professional" decks could handle the lower frequency.)
There is relatively little difference in audible quality between 44.1KHz and 48KHz, since the slight increase in frequency response is outside the range of human hearing. Some inaudible tones produce "beats" with audible tones and thus have a noticeable impact, but the improvement from 44.1 to 48 is marginal at best.
Actually, .CDA files aren't really files at all. Windows shows the tracks on an audio CD as ".CDA" files for convenience. For example, you can create a file association for ".CDA" and invoke an audio CD player when you double-click on a track.
The tracks themselves are in a format almost identical to a common WAV or AIFF file. See section (2-20).
DD-R and DD-RW are Sony standards for "double-density" recordable and rewritable discs. The discs hold 1.3GB of data, and are relatively inexpensive, but aren't compatible with current CD or DVD players. You can only read the discs in a DD-R/DD-RW drive.
The recorders form a middle ground between CD-R and DVD-R in terms of storage capacity and price, but the lack of compatibility reduces their usefulness. On the bright side, the drives are expected to be able to record on CD-R and CD-RW media.
ATIP is an acronym for Absolute Time In Pregroove. All CD-R and CD-RW discs have a pre-cut spiral groove that wobbles slightly. The groove keeps the write head tracking properly, and the wobble (sinusoidal with a frequency of 22.05KHz) provides timing information to the recorder. The wobble is frequency-modulated with a +/-1KHz signal, which creates an absolute time clocking signal, known as the Absolute Time In Pregroove (ATIP).
In the lead-in area, which is at the start of the disc, the ATIP signal can be read to get some information about the disc. The only really useful bit of information is the number of blocks on the disc, which is determined by the length of the pre-formed groove.
The ATIP signal also holds some information about the disc's construction and manufacturer, but see section (2-33) for some comments about their usefulness. http://www.orangeforum.or.jp/e/reference/index.htm used to have ATIP information, but the "Disc Identification Method" link is now password-protected.
"ML" is short for "MultiLevel". Devices and media constructed by Calimetrics (http://www.calimetrics.com/) boast 3x the storage capacity and 3x the recording speed of conventional CD-R and CD-RW media.
CD technology works by measuring the light reflected from the surface of the disc. Traditional discs only have two levels ("pit" and "land"), ML discs have more than one. By increasing the effective bit density of the media, you can write 3x as much data in one revolution of the disc, improving both the storage capacity and the recording speed.
The technology requires minor changes to existing hardware, and requires discs optimized for ML recording. Discs written with ML devices will not be compatible with existing CD players and CD-ROM drives. However, ML recorders are expected to be able to record on CD-R/CD-RW media as well, so ML support could be a low-cost bonus feature on new drives.
[ Announced in early 2002, this never really materialized as a consumer CD technology. ]
CD-MRW is the working name for a CD-RW storage format under development by the Mount Rainier Working Group (http://www.mt-rainier.org/). The Mount Rainier group is creating specifications for native OS support of CD-RW and DVD+RW, with the eventual goal of replacing floppies and similar formats (e.g. Zip disks).
This new standard is being promoted by Compaq, Microsoft, Philips, and Sony. The web site claims support by "over 40 industry leaders", including OS vendors and PC OEMs.
What this means to you: 500+MB of reasonably fast storage that doesn't require long formatting delays or the installation of special software.
Yamaha's CRW3200 claims to be the first CD-RW drive with CD-MRW support.
Yamaha developed Audio Master Quality Recording to compensate for higher "jitter" in recorded CDs. This is not the kind of jitter addressed by "jitter correction" in CD rippers (2-15). This is the "jitter" that people selling fancy stereo equipment talk about.
Jitter is time-base error. It's not a corruption of the digital '1's and '0's, it's a distortion of the timing in which the '1's and '0's arrive at their destination. This doesn't affect extraction of audio, so you don't need to worry about this kind of jitter when reading a CD or ripping to MP3. You do need to worry about it when listening to a CD.
The digital signal is read from a CD via an analog process: bouncing a laser off of "pits" and "lands" on a CD. Various factors can prevent the signals from arriving at the right place at exactly the right time. High-end CD players can correct these anomalies, but many don't.
AMQ extends the length of the pits and lands on the CD in an attempt to produce a more stable signal. This reduces the recordable length of the CD -- a 74-minute disc only holds 63 -- but produces noticeably improved audio (says Yamaha). The process works because CD players automatically adjust the rotation speed.
Yamaha's explanation: http://www.yamaha.ca/computer/cp_AudioMQR.asp
The canonical jitter discussion: http://www.digido.com/jitteressay.html
If you've ever looked at a recorded CD-R, you've probably noticed that the recorded and unrecorded areas have a different appearance. This is usually visible as a slight change in color. By controlling the write laser it's possible to mark the disc in a way that is meaningful to the human eye rather than to a CD player. Unfortunately, the level of control required to do this isn't achievable without firmware support.
In mid-2002, Yamaha announced "DiscT@2" (disc tattoo). This allows moderate-resolution (approx. 250dpi) graphics to be drawn in the parts of the disc that weren't recorded. Yamaha claims to get 256 shades of color (green, blue, or whatever color the disc happens to be), though it works best on dark blue azo discs. For more details and some pictures, see:
This section is for people who really want to know what's going on inside. You absolutely do not need to understand any of this to successfully record a CD. You will come away with a greater appreciation for CD players, and also may better understand how some forms of copy protection function.
The sections are written from the perspective of reading a disc. Generally speaking, the process is simply reversed when writing.
I tried to find a balance between not presenting enough information and presenting too much detail. My hope is that, when you are done reading this, you will have a broad understanding of how a CD player turns a lumpy piece of plastic into music, and will know exactly where to look if you need further details. If you want the kind of detail found in a textbook, there are some good ones listed in section (2-43-6).
CD players use a near-infrared 780nm laser. The visible light spectrum is generally considered to be 400nm to 700nm; few people can see light past 720nm. (DVD, by contrast, uses a visible red 635nm or 650nm laser.)
The drive shines a laser through the polycarbonate (plastic) on the "bottom" of the disc. This bounces off the reflective layer, passes back through the polycarbonate, and is read by a photosensor in the drive head. The index of refraction for polycarbonate is about 1.55, so laser light bends when it enters, allowing a much finer focus for the laser (from 800um at the bottom of the polycarbonate down to about 1.7um at the metal surface). This minimizes the effects of dust and scratches, because the effects of any surface gunk are reduced as the laser's focus width is reduced. A 400um-wide piece of dust on the surface of a CD would completely block a laser focused down to 200um at the surface, but has little effect on a CD player.
If the photosensor sees a strong beam -- the CD standard requires the signal strength to be at least 70% when fully reflected -- it knows it's travelling over a "land". If it sees a weaker response, it's travelling over a "pit". Technically, it's travelling "under" a pit or land, so from its perspective a "pit" is actually a bump. The height of the bump is 1/4 of the laser's wavelength when travelling in polycarbonate, so that light reflected from the bump has a phase difference of one-half wavelength. The light reflected from the pit and from the surrounding land thus cancel each other out. (The geometries are actually such that a "pit" reflects about 25% of the intensity rather than 0%. For example, pits are 0.5um wide, or about 1/3 of the focused width of the laser.)
There are a lot of optical tricks involving polarization of light and the action of diffraction gratings going on. For example, the read head uses a three-beam auto-focus system that keeps the laser properly aligned on the spiral track and at the correct distance from the bottom of the disc. (Side note: if adjacent loops of the spiral are too close together -- the "track pitch" is too small -- the laser tracking can fail. This is why 90- and 99-minute discs are harder to write and read.) It's also worth mentioning that, because light travels more slowly in polycarbonate, the wavelength of the laser inside the CD is closer to 500nm.
CD-R and CD-RW discs do not have pits and lands. On CD-R media, the write laser heats the organic dye to approximately 250 degrees Celsius, causing it to melt and/or chemically decompose to form a depression or mark in the recording layer. The marks create the decreased reflectivity required by the read laser. On CD-RW media, the write laser changes the material between crystalline (25% reflectivity) and amorphous (15% reflectivity) states. This is done by either heating it above its melting point (500C to 700C) and letting it cool rapidly to convert it to amorphous form, or heating it to its transition point (200C) and letting it cool slowly to return it to the more stable crystalline state. The lower reflectivity of CD-RW makes the discs unreadable on most older players.
The rest of this discussion refers to "pits" and "lands", but applies equally to pressed CDs, CD-Rs, and CD-RWs.
The pits and lands on a CD do not directly correspond to 1s and 0s. The start and end of a pit (i.e. the pit edges) each correspond to 1s, and all other areas -- both in pits and on lands -- correspond to 0s. The number of zeroes between pit edges is determined through careful timing. This is an efficient approach that produces an easy to handle electrical signal (it's NRZI -- NonReturn to Zero Inverted -- which converts easily to NRZ where 1s are high voltage and 0s are low voltage).
The careful timing is possible because CDs are essentially self-clocking. Suppose you have a clock that ticks once per second. Plug your ears and count seconds to yourself, trying to keep the same pace as the clock. After ten seconds, unplug your ears. If you've drifted slightly, you can readjust to the clock without worrying that you've too far off. You might be missing the beat by a quarter of a second, but you can adjust forward or backward a fraction of a second and still be sure that both you and the clock got to 10 seconds at about the same time. Now try the same experiment for 10 minutes. When you unplug your ears you can get back in sync with the clock's timing, but unless you have a very good internal timer it's unlikely you will reach 10 minutes on the same tick. With your ears plugged for so long, you are likely to be off by several seconds.
CDs work the same way. Every pit edge represents an audible clock tick, while the insides of pits and lands represent inaudible ticks. If a pit or land is too long, the drive's clock will drift too far and possibly get out of sync. (This is why "blank" recordable discs aren't entirely blank: they have a pre-cut spiral groove with a "wobble" that the recorder can use as a timing signal. A clock accurate enough to produce a stable, reliable signal at these frequencies is too expensive to incorporate into a cheap consumer product. The 22.05KHz wobble is frequency-modulated by +/-1KHz to create the ATIP signal that, in the lead-in area, holds some bits of information about the disc.)
To guarantee pits of specific lengths, the CD standard requires that there are at least 2 and at most 10 zeroes between every 1. This is achieved by converting every 8-bit byte into a 14-bit value, a process called Eight to Fourteen Modulation (EFM).
The shortest possible pit (or land) thus represents 3 EFM bits (100), and the longest 11 EFM bits (10000000000). If a single bit requires time T to pass under the read head, then pits of these lengths can be referred to as 3T pits and 11T pits. If after seeking to a new location, the drive sees a pit shorter than 3T or longer than 11T, then it immediately knows that the disc is not spinning at the rate it was expecting, and can make appropriate adjustments.
Between each 14-bit EFM word there are 3 "merging bits". Because CDs aren't allowed to have runs shorter than 3T or longer than 11T, it is sometimes necessary to follow an EFM code with a 1 or 0. Suppose, for example, that an EFM code ending in 1 were immediately followed by an EFM code starting with 1. The merging bits also serve to prevent the frame synchronization pattern from appearing where it isn't supposed to (see next section).
If there is more than one possible arrangement of merging bits that satisfy the restrictions for run length and sync pattern, then a pattern is chosen that minimizes the low-frequency components of the signal. This is done by minimizing the Digital Sum Value (DSV), computed by adding one to a counter for every T after a transition to a land, and subtracting one for every T after a transition to a pit. Adding a 1 to the merging bits inverts the signal by causing a transition from a pit to a land or vice-versa. Minimizing the DSV is important because low-frequency signals can interfere with the operation of tracking and focusing servos.
With EFM there are more bits to encode, but the highest frequency possible in the output signal is decreased. The ratio of the number of bits transmitted to the number of transitions on the medium is high, making this an efficient way to store the data while still being able to recover the clock. It's also worth noting that a 3T pit is 0.833um long, while the laser spot is just over twice that length at 1.7um. If 2T or 1T pits were allowed, the laser would have a hard time detecting them. This is why it's important that transitions not occur too frequently: the laser is good at computing the time between transitions, but isn't so good at noticing transitions if they follow each other too quickly. Making the transitions more obvious requires making the pits and lands longer, which reduces the amount of data that will fit on the disc. (See the description of AMQ in section (2-41).)
EFM encoding is applied to a series of bytes called a "frame". Some people refer to a CD sector as a "frame", but that's incorrect. A frame holds 24 bytes of user data, 1 byte of subcode data, and 8 bytes of parity (error correction), for a total of 33 bytes.
When read from the disc, each frame is preceded by a 24-bit synchronization pattern and 3 merging bits. The sync data has a unique pattern not found elsewhere on the disc, and it ensures the read head correctly finds the start of the frame. (The pattern is 100000000001000000000010, three transitions separated by 11T, which can't occur otherwise because the merging bits are specifically chosen to prevent it.) If you don't understand why having a sync field is important, remember that every time the read head seeks to a new part of the disc or is confused by a scratch, it has to start reading in the middle of a stream of 1s and 0s and try to make sense of what it's reading. Until it sees a synchronization pattern, it has no idea if it's reading the start or middle of a frame, or even if it's at the start or middle of an EFM word.
The rest of the 33-byte frame is read as 14-bit EFM values followed by 3 merging bits. This means there are 588 (24 + 3 + (14+3)*33) "channel bits" in a frame. This 588-bit structure is called a "Channel Frame".
Once EFM is decoded and the merging bits discarded, we are left with an "F3 Frame". The subcode byte is removed, and the remaining data (now an "F2 Frame") is passed into the CIRC (Cross-Interleave Read-Solomon) decoder. The decoder is an important part of the reason why CDs and CD-ROMs work.
The raw error rate from a CD is around 1 error per 100K to 1 million bits. That's pretty good, but at 4 million bits per second (588 channel bits per frame x 98 frames per sector x 75 sectors per second = 4.3218Mbps), the errors add up quickly. CIRC encoding takes the 192 bits (24 bytes) of data and 64 bits (8 bytes) of parity, shuffles it around, and performs some weird math involving Galois Fields. The bits are processed by two error correction stages, referred to as C1 and C2. The efficacy of the results can be expressed as a set of error counts.
Errors are noted with a two-digit number that indicates the number of errors with the first digit and the CIRC decoder stage with the second digit. The E11 count indicates the number of single-symbol (correctable) errors in the C1 decoder. E21 indicates double-symbol (correctable) errors in C1, and E31 indicates triple-symbol (uncorrectable at C1) errors in C1. The sum of these counts is the Block Error Rate (BLER), a measure of correctable and uncorrectable errors. The CD standard sets the acceptable limit to 220 BLER errors per second, averaged over a 10-second stretch.
The E12 count indicates the number of single-symbol (correctable) errors in the C2 decoder. Because the data is interleaved after the C1 pass, one E31 error can generate up to 30 E12 errors, so a high error count here is not problematic. E22 counts double-symbol (correctable) errors, which are a bad sign. The sum of E21 and E22 form a burst error count (BST), which can be used to identify physical defects on a disc.
Any E32 errors, representing triple-symbol (uncorrectable) errors in the C2 decoder, result in damaged data. For an audio CD interpolation is performed, for a CD-ROM the damaged data must be repaired at a higher level. (This, incidentally, explains how some forms of audio CD copy protection work. The CD author introduces deliberate uncorrectable errors to the CD. An audio player will inaudibly interpolate across them, but a CD-ROM performing digital audio extraction will simply return the bad bits.)
With CIRC, the bit error rate is reduced to one in 10 to 100 billion. The 24 bytes that comes out of the CIRC decoder are referred to as an "F1 Frame".
It's worth noting that the subcode channels are not CIRC-encoded, and hence are the least-reliable storage directly accessible to the user. The EFM encoding provides some protection against single-bit errors, because only 256 of the 16,384 possible combinations are valid, but without any parity bits the best the drive can do is tell you that it failed to read the data correctly. The Q subcode channel, which can hold vital information about the disc, has a 16-bit CRC.
98 frames of 24 bytes are combined to form a 2352-byte sector and 98 bytes of subcode data. The sector is assembled from F1 Frames, which are byte-swapped, shuffled, and run through a descrambler. The purpose of the scrambler is to reduce the likelihood that regular bit patterns will induce a large digital sum value.
It should be pointed out that the 2352-byte sector is the smallest unit most CD-ROM drives will allow software to manipulate. It's only after all of the above that low-level CD-ROM operations, like "RAW DAO-96" reads and writes, begin. This is why making a "bit-for-bit" copy of a disc is tricky.
A sector on an audio CD holds 2352 bytes of data. 16-bit stereo samples require 4 bytes per sample, so there's 2352/4 = 588 samples per sector. At 75 sectors per second, that's 44100 samples per second (44.1KHz). At this point, the processing for an audio CD is essentially complete. CD players feed the samples through a DAC (or S/PDIF connector) and eventually out to the speakers, and send the subcode data to the front panel controller so it can update the HH:MM counter and track number.
A sector on a CD-ROM holds 2048 bytes of user data, leaving 304 bytes for other purposes. Every data sector begins with a 16-byte header:
The mode byte determines what the remaining 2336 bytes in the sector looks like:
CD-ROM/XA (eXtended Architecture) Mode 2 extends the definition of a Mode 2 CD-ROM. Form 1 looks like a slight rearrangement of a Mode 1 sector, with the 8 bytes of space moved ahead of the user data and filled with a sub-header. Form 2, intended for compressed audio/video data, has the 8-byte sub-header, 2324 bytes of data, and an optional 4-byte EDC code. The sub-header contains some channel and data type flags.
A CD session must be written in a single mode, but the XA spec allows the form to change. Using CD-ROM/XA Mode 2 allows you to choose between extended error correction and increased data capacity, and also change your mind several times in a single track.
There are 8 subcode channels, labeled P,Q,R,S,T,U,V,W, or sometimes "P-W" for short. (The ECMA-130 standard refers to subcode bytes as "Control bytes".) Every frame contains one byte of subcode data, and each byte holds 1 bit of P, 1 of Q, and so on. The bytes from 98 consecutive frames are combined to form a subcode "section". The first two bits in each channel are used for synchronization, leaving 96 bits of useful data per channel (which is where RAW DAO-96 gets its name).
The P and Q channels are defined by the CD audio standard. (They are unrelated to the P and Q parity fields.) The P channel can be used to find the start of a track, but in practice most devices use the more sophisticated Q channel. Q contains four chunks of information: control (4 bits), address (4 bits), Q data (72 bits), and an EDC (16-bit CRC).
The control bits determine whether the track holds audio or data, the number of audio channels (stereo or quadraphonic), and specifies the Digital Copy Permitted and Pre-emphasis flags. The address bits determine the format of the Q data section. Address mode 1 holds information about tracks, mode 2 holds a catalog number (such as a UPC code, constant for an entire disc), and mode 3 contains the ISRC (International Standard Recording Code, constant for a given track but may change with each track).
A disc has three main regions: the lead-in area, the program area, and the lead-out area. Subcode Q mode 1 data in the lead-in is used to hold the table of contents (TOC) for the disc. The TOC is repeated continuously in the lead-in area in case of damage (remember, no CIRC encoding on subcode channels). In the program and lead-out area, mode 1 contains track numbers, index numbers, time within the current track, and absolute time. Index 0 marks the start of a pregap (pause) before the audio in a track begins, index 1 marks the start of the music, and indexes 2 through 99 are usually not set but can be added if desired.
The ability to specify track and index markers when writing a Red Book audio CD is often referred to as "PQ editing" because that information is contained in the P and Q subcodes.
Subcode channels R through W are not defined by the CD standard, except to say that they should be set entirely to zero if not used. They're currently used for CD+G (e.g. Karaoke) discs, CD-Text, and some forms of copy protection.
It is interesting to note that, while bytes from 98 consecutive frames are used to create a subcode "section", those frames don't have to be from a single sector. It's possible for a subcode section to start in one sector and end in the next.
An excellent reference for is Ken Pohlmann's mammoth _Principles of Digital Audio, 4th edition_ (ISBN 0-07-134819-0), especially chapter 9 (on compact discs) and chapter 5 (on error correction). If you want something a little slimmer, try his older _The Compact Disc Handbook, 2nd edition_, 1992 (ISBN 0-89579-300-8).
Another good book is _The Art of Digital Audio_, 2nd edition, by John Watkinson, Focal Press, 1994 (ISBN 0-240-51320-7).
http://www.ee.washington.edu/conselec/CE/kuhn/cdmulti/cdhome.htm has a number of interesting pages. In particular, there's a good page about CIRC on http://www.ee.washington.edu/conselec/CE/kuhn/cdmulti/95x7/iec908.htm, and http://www.ee.washington.edu/conselec/CE/kuhn/cdaudio/95x6.htm has a nice explanation of disc construction and optics, especially the three-beam autofocus.
The page at http://www.tc.umn.edu/~erick205/Papers/paper.html provides some background information on sampling, aliasing, dither, DACs, and other relevant topics.
You can get a copy of ECMA-130 from http://www.ecma.ch/. This document describes the format of a CD-ROM, including physical dimensions and optical characteristics, as well as sector formats and Q-channel specs. It also features some interesting annexes:
If you want source code for the CIRC, RSPC, EDC, and scramble functions, look for Heiko Eissfeldt's edc_ecc.c (and related files). The code is part of Mode2CDMaker, CDRDAO, and possibly others.
If you want an explanation of DSV and the problems associated with it, read the Philips patent on the sector scrambler (US4603413), or one of the associated patents on removal of DC content from a digital signal. The full text of the patent can be found at http://www.uspto.gov/. In brief:
"[...] If the frequency of such oscillation is comparatively high, during the read operation the decision level for detection of the channel bit signals may be rendered inaccurate. As a result, read-out of the information will be disturbed to such an extent that even the error-correction measures cannot prevent errors. Moreover, the tracking system for controlling the read laser which reads the channel bits may become incapable of keeping the laser beam accurately positioned on the track."It appears that, when the DC offset in the signal becomes too large, the read head has trouble "seeing" the disc. The voltage level in the photodetector has pegged, so the difference between a pit and a land is unnoticeable.
For some technical information on how CD-Rs are constructed, look through the uspto.gov site for relevant patents. For example, US5348841 describes "Organic dye-in-polymer (DIP) medium for write-once-read-many (WORM) optical discs".
Digital audio CDs are superior to audio cassettes and 8-track tapes, and digital video DVDs are superior VHS videotapes. However, the analog film shown in a movie theater is superior to DVD, and the analog studio master tape is better than an audio CD. The sounds that an Apple II makes are generated digitally, but you wouldn't want to play your CDs that way.
Some formats are better than others. The low-cost consumer digital formats are generally superior to low-cost consumer analog formats (except perhaps for 35mm film, though that's changing). This does not mean that "digital" is better than "analog", though many people have that impression because the consumer electronics companies are marketing products that way.
Digital has some advantages over analog. The most significant is the ability to apply various algorithms to reproduce the original digital signal. With most forms of analog transmission, reconstructing the original signal without noise and distortions is difficult. The flip side is that, with too much interference, the digital signal becomes unusable. NTSC televisions (the kind used in North America and Japan) can display a transmission with a negative S/N ratio, i.e. there's more noise than signal. (If you're not part of the "cable TV" generation, think about a picture that was heavily snowed, but still decipherable. It was probably a sporting event.)
Digital also has disadvantages, although many of them can be minimized through careful system design. The most fundamental problem is the need to convert the digital signal back to analog. Human senses are analog, so audio has to be converted to voltages that drive speakers, and video needs to be turned into pixels on a screen. The human eye is pretty easy to fool -- update the image quickly enough and the brain will believe the motion is smooth -- but the ear is more discerning. Slight changes in frequency and timing, especially in a stereo signal, can be detected.
Many digital formats are compressed with "lossy" techniques. Algorithms like MPEG-2, MP3, DTS, and SDDS remove parts of the music to reduce the storage size. The parts removed are usually inaudible, though that depends on how much is removed and how good your ears are.
The upshot of all this is that it's wise to pay attention to what you're getting. Don't assume that a digital format is better just because it's digital.
Computers store things in "bits", which can be either 0 or 1. To store something in a computer, it must be converted to a series of bits. The process is called "digitizing".
You've probably seen an egg slicer. If you haven't, picture a device that looks like a book resting flat on table. Instead of pages it has an egg-shaped depression, and instead of a front cover it has a frame with thin wires stretched across it vertically at regular intervals. You raise the lid, insert the egg, and when you press the lid down the wires cut the egg into thin, round slices.
It usually helps to hard-boil the egg first.
Suppose we want to digitize an egg so we can make a nifty 3D model and display it on a computer. Our slicer has 9 wires, so we could end up with as many as 10 pieces. We place the egg into the device and slice it. Now we measure the height of each piece in centimeters (assume the pieces are perfectly round), measuring the diameter with calipers and rounding it to the nearest centimeter. Each slice could go from 0cm (the egg was short, so there was no slice) to 5cm (the width of our slicer).
When we're done, we spit out something that looks like this:
When we try to display our digitized egg on a computer screen, however, we discover a problem. The image doesn't look like a smooth egg. Instead, it looks like a bunch of stair steps in a vaguely egg-shaped pattern. The sizes aren't right either: our original egg was actually 3.4cm at its widest point, but we had to round it down to 3cm.
Suppose we improve our measurements down to the nearest millimeter. Now, when we have to round off the measurements, the round-off error is much smaller. The results look much better, but holding a value from 0 to 50 requires 6 digital bits instead of 3, so we've doubled our storage requirements to 60 bits. What's more, the image still looks stair-steppy.
The stairs happen because each slice has a single height value. When we go from slice #7 to slice #8, we abruptly jump from 3cm to 2cm. The reason our recreated egg doesn't look smooth is because we didn't really capture the original, in which each slice varied in height from one edge to the other. Our digitization could only capture the average height of each slice.
There are a couple of ways to improve this. The first is to guess at the shape of the original egg, and draw smooth curves based on the data we have. This is called "interpolation". The other approach is to buy a new egg slicer with wires that are closer together, so we have more slices, reducing the size of the jump from one slice to the next. This is called "increasing the sampling rate". If you double the number of slices, you double the number of bits required to hold the digital version.
If you slice the egg finely and measure it accurately, you can get a nearly perfect representation of the original. For example, if we create slices that are one molecule apart, and measure the height to the nearest molecule, we will have an extremely accurate picture, not to mention a seriously huge digital representation. The tricky part about digitizing something is to choose the height and thickness of the slices such that the likeness is very good but the digital size is small.
An audio CD cuts a one-second "egg" of sound into 44100 slices, and measures the "height" of each slice from 0 to 65535 (16 bits). It does this independently for the left and right stereo channels, using a format called Pulse-Code Modulation, or PCM. The technical shorthand, which you may have seen in a sound editor, is "44.1KHz 16-bit stereo PCM".
Measuring the "height" of each slice is called quantizing. The round-off error in the measurements is called quantization error. The problems associated with the error can be reduced by applying "dither" (low-level noise).
The reason for the number 44100 is explained in section (2-35). The choice of 16 bits is also fairly arbitrary, but extremely convenient on a computer.
There are other problems when digitizing (e.g. aliasing) and when converting back to analog form (e.g. jitter). See http://www.tc.umn.edu/~erick205/Papers/paper.html for an introduction.
Newer audio formats, such as Super Audio CD and DVD-Audio, offer different sampling rates (up to 96000), quantization (up to 24 bits), and numbers of channels (e.g. 5.1 surround-sound).
The term "CDR-ROM" was coined by Optical Disc Corporation in a February 2003 press release, and refers to a disc with writable and non-writable components. Some possible uses include burning a unique serial number on a full CD-ROM, or providing recordable discs with marketing content (e.g. a few tracks of audio to which more music can be added). More information can be found at http://www.optical-disc.com/.
Eastman Kodak had a similar product, called the "CD-PROM", a few years earlier. According to their web site, marketing and sales of the CD-PROM was discontinued in October 2002. See the notice on http://www.kodak.com/US/en/digital/progCDR/.
In April 2003, a few companies began announcing technologies that allow you to store larger quantities of data on standard CD-R media. Unlike DD-R and "ML" technology, special discs aren't required. The capacity and compatibility is different for each.
This is general information about recommended ways to do specific tasks.
Just about every piece of CD recording software comes with a CD copier. In some cases it's a stand-alone extra, in some it's integrated with other features, and in a few cases the software does nothing else.
Most disc copying software will allow you to make a CD image on a hard drive that can then be written to multiple CDs. A few will allow you to record the same image to multiple CD recorders simultaneously (see section (3-17)).
It's important to remember that, when copying directly from one CD to another, the source MUST be faster than the target, and must be error-free. If the source pauses or spins down to read a marginal area of the disc, the target may outrun the source, and the CD-R will only be useful as a frisbee. Most programs have a "test write" feature that put the CD-R device into a mode where it goes through all the motions but doesn't actually write anything; it's a good idea to do this right before copying something for the first time.
If you're wondering about copying Mac CD-ROMs on a PC or vice-versa, see section (3-50).
Some suggestions for software good at copying a variety of discs:
See section (2-4) for more information about copy protection, section (3-51) for the details on "RAW" reads, and (3-4) for some notes on game console discs.
CDs don't have circular tracks. They're laid out on a spiral, with multiple sessions composed of multiple tracks composed of sectors, and the data in the sectors is interleaved and spread over a large area. The sector format is standard, but there's more than one standard.
"The nice thing about standards is that you have so many to choose from."
-- Andrew S. Tanenbaum, _Computer Networks_, 2nd ed, p.254
The ability to read certain portions of a CD depends on the CD firmware. Some CD players aren't capable of understanding multi-session discs or of reading audio tracks as digital data. Jitter, described in section (2-15), is also a problem for most drives.
Start with the CD-DA FAQ [once at http://www.tardis.ed.ac.uk/~psyche/cdda/, currently missing?] Take a look at http://come.to/cdspeed to see if your CD-ROM drive is up to the task. EAC, from http://www.exactaudiocopy.de/, is often recommended for extracting ("ripping") audio tracks.
To copy from CD to CD, the source drive needs to support digital audio extraction, which is rare among older drives but universal in current models. Ideally, the copy program will use disc-at-once recording to produce a duplicate that mimics the original as closely as possible. As with copying CD-ROMs, you must be able to read data off of the source drive faster than your recorder is writing. If you can only extract audio at 1x, you're not going to be able to do a CD-to-CD copy reliably.
If you're just interested in extracting digital audio, you don't even need a CD-R unit, just a CD-ROM drive that supports Digital Audio Extraction (DAE) and some software. The CD-DA sites noted at the top of this section list drives that support DAE, have software to evaluate your existing drive, and have links to several different DAE applications.
Different drives can extract digital audio at different speeds. For example, the Plextor 6Plex can extract audio at 6x, while the NEC 6Xi can only extract at 1x. Most recent drives extract at well over 20x, which is about the limit for an IDE drive that doesn't support DMA.
Some CD-ROM and CD-R drives have trouble extracting digital audio at high speed, so if you're getting lots of clicks and pops when extracting you should try doing it at a slower speed. You may also run into trouble if you try to extract faster than your hard drive can write. One user found that he was able to eliminate clicks and pops by defragmenting his hard drive. Another found that the Win95 "vcache" fix (section (4-1-2)) solved his problems.
It should be pointed out that, while digitally extracted audio is an exact copy of the data on the CD, it's an exact copy as your CD player perceives it. Different drives or different runs with the same drive can extract slightly different data from the same disc. The differences are usually inaudible, however. Some newer drives will report the number of uncorrectable errors encountered, so you can get a sense for how accurate the extraction really is.
The quality of the audio on the duplicate CD-R, given a high-quality extraction, depends mostly on how well your CD player gets along with the brand of media you're using. See the next section for some comments about avoiding clicks and pops.
Some older drives have trouble starting at the exact start of audio tracks. The extraction starts a few blocks forward of where it should, and ends a few blocks later, so the track may not sound quite right and the extraction program will report errors at the end of the last track. See section (4-19).
The Lite-On LTN483S 48x CD-ROM drive has a fairly unique bit of brain damage: it doesn't extract the last two seconds of a track correctly. This is only apparent on audio CDs with a "cold stop", where the music plays right up to the very end of the track. If the track has two seconds of silence at the end, there are no apparent problems. Apparently there is a firmware fix for this (the PD03 update), available from http://support.euro.dell.com/de/de/filelib/download/index.asp?fileid=R20664 or http://support.dell.com/us/en/filelib/download/index.asp?fileid=R20664.
One minor note: the data on audio CDs is stored in "Motorola" big-endian format, with the high byte of each 16-bit word first. AIFF files also use this format, but WAV files use "Intel" little-endian format. Make sure your software deals with the endian-flipping correctly. Byte-swapped CD audio sounds like "static".
A common reason for wanting to do this is to have a disc that can be sung along with, either for personal practice or for karaoke. There isn't a perfect method for doing this, but it's possible to get close with some CDs.
Music is generally recorded in independent tracks and then mixed into a balanced whole. The recording studio can create masters with or without the vocals, which is where a "clean" karaoke source comes from. The music is usually recorded in stereo, and the vocals in mono (the singer has one microphone). The mixed result has slightly different signals on the left and right channels for the music, but the same signal on both channels for the vocals. By removing all signal components that are equal on the left and right channels, the vocals can be removed with relatively little distortion of the music. This is called "center channel elimination".
This doesn't always work out in practice. If the track in question doesn't keep the vocals "centered", all bets are off. Many musicians apply effects to the vocals to achieve a certain effect -- often, to make it sound like they can sing better than they actually can. These effects aren't usually "centered", so part of the voice remains.
Center channel elimination can be done with a good sound editor, such as Cool Edit 2000 (6-2-14). The procedure to follow with Cool Edit is:
The converse operation -- extracting the vocals and deleting the music -- is not currently possible. (If you express the situation mathematically, the problem is one of three variables in two equations. The software needs a new feature that subtracts tracks and retains the other part.)
Extract the audio from the CD, then encode it into an MP3 at a quality level you like. Some programs combine the "rip" and "encode" into one easy step.
Higher quality settings result in larger MP3 files. Most people can't tell the difference between an MP3 at 160Kbps and the original.
Some tutorial sites:
If your MP3s have a static sound in them, you might be getting a bad "rip". The all-in-one rip+encode programs don't always do a great job extracting audio from the CD. You may want to "rip" the audio manually with EAC (6-2-12) and then encode the WAV files. (Recent versions of EAC can extract to MP3 if you have a codec installed.)
If you're interested in removing noise from audio captured from an analog source, such as a record player or analog cassette tape, skip to section (3-12-3). This section is about unexpected noise in audio from digital sources, such as tracks extracted from a CD. (Start with section (3-2) if you are new to "ripping" or copying audio tracks.)
The single most important rule of noise removal is to figure out where the noise came from. Play the .WAV files off of your hard drive (if you're doing direct CD-to-CD copies, extract a track and listen to it). If you hear noise in the .WAV on your hard drive, the digital audio extraction isn't working very well. You either need to extract more slowly, extract from a different device, find a program that works better, or maybe just clean the dust and grime off the source CD. For more information, including a URL for recommended software and the CD-DA FAQ, see section (3-2).
Always start by inspecting the CD. If you borrowed it from a library, don't expect it to be in pristine condition. With enough abuse, even CDs will sound bad, and audio *extraction* is more susceptible to such errors than audio *playback*. (This is what makes copy-protected CDs possible; see section (2-4-2).)
If the problem sounds like repeated or skipped samples, rather than clicks or hissing, the problem is probably jitter during extraction. See section (2-15) for an overview, and then give EAC a try (section (6-2-12)).
A nifty trick for comparing two .WAV files is to use the "Mix Paste" feature in Cool Edit. Extract a track twice, then use Mix Paste to copy an inverted version of one file on top of the other. The two sound files will cancel each other out wherever they are identical, and have little spikes where they are different. This can be useful for seeing if the problems are only on one channel or are happening at regular intervals. You need to make sure though that both files start at the same place though. If your CD-ROM drive doesn't always extract from the start of the block, you will need to adjust the files so they line up.
Useful things to do with this include comparing two extractions from the same drive, extractions from different drives, or extractions from the CD-R you just wrote to the original .WAV file you used to write it.
If you just want to see if the files are the same, use the DOS File Compare command, with the "binary" switch set: FC /B FILE1.WAV FILE2.WAV.
Some CD-ROM drives may put a click a few seconds into the first track being extracted. This appears to be related to the drive spinning up. Try starting the extraction, cancelling, and then immediately restarting.
It is possible, though still somewhat unlikely, that you are trying to extract from a copy-protected CD. Section (2-4-2) discusses this in some detail.
The rest of this section only applies if the extracted audio sounds fine on disk, but has problems when played back from the CD-R.
If you're using track-at-once recording, you may get a short click or silent "hiccup" at the start of each track. Hiccups are unavoidable, but you should be able to get rid of the click by using different software.
If you're using disc-at-once recording, and are still getting a short click at the *start* of every track, then your recording software is probably writing the sound file with the headers still on it. You should either use a smarter program, or remove the header manually (see the URL for "StripWav", below).
If you are getting clicks in the middle of a track, they are either being added when pulling the data off the disc or when writing it. If the .WAV (AIFF on the Mac) file plays without clicks, then your CD recorder may be failing somehow during the write process. Some people who got "static" in audio recorded on an HP 4020i found that reducing the DMA transfer rate to 2MB/sec helped.
One user was told by Yamaha tech support that crackling (similar to a dirty vinyl LP) was a symptom of laser misalignment. If you've been writing audio CDs for quite a while, but lately you've been getting "crackly" results from tried-and-true media, this might be the culprit. Since it requires returning the unit for repair, you should exhaust all other possibilities first. (Side note: it's not clear how a laser gets "misaligned". They have to adjust themselves constantly to stay in the spiral groove. It might be due to poor focus, but that should be causing all kinds of problems.)
If you are getting clicks at the end of a track, it's possible that the software used to create the .WAV file put some information at the very end, which is legal but not handled correctly by some CD-R software. See section (3-12-3) for tips on using CoolEdit to remove the data. If you are finding that tracks extracted from CDs don't have clicks but tracks that you have recorded or edited do, chances are the data size isn't a multiple of 2352 bytes, and the last block is being filled with junk. This is common on live recordings or when large tracks are cut into smaller ones. Jeff Arnold's DAO will fill out the last block with zeros (digital silence) if there is space left over, but most of the other programs will write garbage that is audible as a short (less than 1/75th second) click. The fix is to split the track on 2352-byte block boundaries.
A program called "StripWav" will remove .WAV headers and footers that may be interfering with some applications. The program is available from http://www.lightlink.com/tjweber/.
If you must use track-at-once, make sure you're writing it all in one session. PC-based CD players may be able to see tracks in later sessions, but the CD player in your stereo system almost certainly can't.
A distantly related problem can arise if you use "shuffle play" to play random tracks from a CD-R. If the audio of track N begins immediately, some CD players will slide from the end of track N-1 into the start of track N, playing a short burst of track N before seeking elsewhere. This can be avoided by putting a gap at the start of such tracks (e.g. with "INDEX 01 xx:yy:zz" in a DAO cue sheet).
For PCs, CloneCD (6-1-49) or CDRWIN (6-1-7) should work as well as anything. For Macs, Astarte's CD-Copy (6-2-8) used to be recommended but may no longer be available.
Note that the software does NOT defeat the copy protection. I'm told that the "copy protection" on Playstation discs is in fact a region code -- America, Europe, Japan -- encoded near the start of the disc. The "MOD chip", a device attached to the Playstation that defeats one aspect of the copy protection, emulates the country code reading process. It sends all three region codes back, enabling the game console to play original discs from other regions as well as copied discs. Some people say the code is written in a block with damaged ECC, some say it's in the barcode on the hub, others have insisted that it's in the ATIP region of the lead-in. Whatever the case, it doesn't get copied by a CD recorder, and claims of hacked recorder firmware that can create MOD-chip-free duplicates are false.
Instructions for copying discs and vendors who sell MOD chips can be found by searching the net. If you don't have a PC, or if your drive doesn't support disc-at-once recording, you will need to look for disc copying instructions on the net.
Sega Dreamcast discs use a proprietary format, called GD-ROM, which can hold 1GB of data. This makes it impossible to make an exact copy, though it is possible in many cases to copy "enough" stuff to make them work. Persistent rumors claiming that CeQuadrat's PacketCD can copy the discs are false. GD-R (Gigabyte Disc Recordable) media has two regions, a "single-density" area near the hub and a "high-density" area farther out. A visual inspection of GD-R media suggests that the single-density area starts at about 22mm from the disc's center (same as a CD-R) and goes to 29mm. From 29mm to 31mm is a "no-mans" land that isn't recordable, and the high-density area goes from 31mm to 58mm. An image of one is available on http://www.fadden.com/cdrpics/.
Incidentally, posting requests or advertisements for pirated software on one of the non-warez Usenet groups is generally regarded as a mark of extreme stupidity. Whatever your opinion of software piracy, it is against the law in much of the world.
There are several different ways, most of which only work with some operating systems. The next few sections discuss the various methods. See http://www.roxio.com/en/support/cdr/filesystems.html for a compatibility chart.
It's important to remember that the most common CD filesystem (ISO-9660 Level 1) only supports eight-character filenames with a three-character extension. Longer filenames are added either as an extension to ISO-9660 (Joliet, Rock Ridge) or a replacement (UDF, HFS). These are discussed in the sections below.
Getting mixed-case filenames onto a disc is a similar problem. Burning an ISO-9660 disc with lower-case filenames isn't recommended, because some systems aren't able to access the files even though they appear in directory listings.
"mkhybrid" and recent versions of "mkisofs" (1.12b1 or later), described in sections (6-1-32) and (6-1-10), respectively, are able to create CDs that have both Joliet and Rock Ridge extensions. "mkhybrid" can create discs with Joliet, Rock Ridge, and Mac HFS on the same disc, sharing the same file data.
Level 1 ISO-9660 defines names to be the familiar 8+3 convention that MS-DOS users have suffered through for many years: eight characters for the name, a period ("full stop" for those of you in the U.K.), followed by three characters for the file type, all in upper case. The only allowed characters are A-Z, 0-9, '.', and '_'. There's also a file version number, separated from the name by a semicolon, but it's usually ignored.
Files must occupy a contiguous range of sectors. This allows a file to be specified with a start block and a count. (Most disk-based filesystems require index blocks that list all the blocks used by a file.) The maximum directory depth is 8.
Level 2 ISO-9660 allows far more flexibility in filenames, but isn't usable on some systems, notably MS-DOS.
Level 3 ISO-9660 allows non-contiguous files, useful if the file was written in multiple packets with packet-writing software. Also unavailable under MS-DOS. For the Mac, you can add support by installing Joliet Volume Access (http://www.tempel.org/joliet/).
Some of the CD creation programs will let you select how closely you want the CD to conform to the ISO-9660 standard. For example, Easy-CD Pro 95 can restrict filenames to be ISO-9660 compliant, or allow the full set of valid MS-DOS filenames. (Most systems can handle MS-DOS filenames.)
Incidentally, the ISO-9660 spec requires that all files be displayed in alphabetical order, with directories first, no matter how they are recorded on the CD-ROM. You can't arrange files on the disc, because the ISO-9660 reader (e.g. MSCDEX) sorts them before displaying them.
The Rock Ridge extensions to ISO-9660 define a way for UNIX-isms like long mixed-case filenames and symbolic links to be supported.
Because it's still an ISO-9660 filesystem, the files can still be read by machines that don't support Rock Ridge; they just won't see the long forms of the names.
Rock Ridge is supported by UNIX systems. DOS, Windows, and the Mac don't currently support it.
Copies of the Rock Ridge standard and System Use Sharing Protocol (SUSP) can be found at ftp://ftp.ymi.com/pub/rockridge/. Pay a visit to http://makecd.core.de/Rock_Ridge_Amiga_Specific for a description of Amiga-specific extensions.
HFS is the Hierarchical File System, used by the Macintosh. This is often used instead of the ISO-9660 filesystem on Mac CD-ROMs, making the disc unusable on systems that don't support HFS.
At present, the systems that can natively read HFS CD-ROMS are Macs, Amigas (with AmiCDROM, available from ftp://ftp.cdrom.com/pub/aminet/disk/cdrom/), PCs running Linux or OS/2 (with appropriate patches), the Apple IIgs, and SGI machines running Irix (they appear as AppleDouble format).
Windows machines can read HFS disks with the appropriate software. One example is "Conversions Plus" from Data Viz, http://www.dataviz.com/products/conversionsplus/. Another is MacDisk, from http://www.macdisk.com/prospen.php3.
Some authoring packages for the Mac and Windows allow the creation of "hybrid" CDs that have both an ISO-9660 filesystem and an HFS filesystem. Such discs can be used on non-Mac systems, but still have all the file attributes (creator type, resource fork) that Mac OS likes.
Apple has defined some ISO-9660 extensions that allow Macintosh files to exist with file and creator types on ISO-9660 CD-ROMs. A description of the extensions is available as tech note FL 36 from: http://developer.apple.com/technotes/fl/fl_36.html
Microsoft, being Microsoft, created their own standard called "Joliet". This is currently supported by Win95 and WinNT. It's useful when doing backups from Win95 onto a CD-R, because the disc is still readable as ISO-9660 but shows the long filenames under Win95. The limit on Joliet filenames is 64 characters. (Some software reportedly allows up to 110.)
The spec can be found at http://bmrc.berkeley.edu/people/chaffee/jolspec.html.
Recent versions of Linux (kernel >= 2.0.34 and 2.1.60) have Joliet support. Older versions can be patched; for details, see http://www-plateau.cs.berkeley.edu/people/chaffee/joliet.html.
To patch Joliet support into OS/2, visit: http://service.software.ibm.com/os2ddpak/html/miscellb/os_2warp/updatedc/index.htm
For the Macintosh, use Joliet Volume Access (http://www.tempel.org/joliet/).
Some old Creative CD-ROM drivers have trouble with CD-ROMs that have Joliet filenames. You may need an updated copy of sbided95.exe. It used to be available from http://www.ctlsg.creaf.com/, but that site no longer exists.
Adaptec's Easy-CD Pro software allowed creation of discs in "Romeo" format. Filenames may be up to 128 characters long, which is very useful for certain types of files. Sadly, this format never really caught on. NTI's CD-Maker software (section (6-1-12)) supports Romeo.
One person reported having trouble reading Romeo-format discs in Win2K, others have had no problems.
These are (relatively) new standards intended to replace ISO-9660. The UDF filesystem specification is based on ISO/IEC 13346 (which is closely related to ECMA-167). For more information about these standards, see the links in section (6-3-1).
Short answer: you don't, unless you have a CD-i add-on board. Even if you have a CD reader compatible with the CD-i (Green Book) standard, there are still a number of obstacles in your way. The filesystem used isn't ISO-9660, and CD-i players are based around a 680x0 CPU and have special hardware for video and audio.
Longer answer: it depends on what kind of disc it is, and what you mean by "use".
PhotoCD and VideoCD discs are CD-ROM/XA "Bridge Format" discs that play on CD-i players as well as dedicated players and computers. These use the ISO-9660 file system, and can be read with commonly available PhotoCD software and MPEG-1 players.
DigitalVideo discs from Philips manufactured before June, 1994 are in CD-i format, not VideoCD format. If your CD-ROM drive supports raw 2352-byte sector reads, it's possible to pull tracks off of a Green Book format disc, and extract audio or MPEG video data. You can get a CD-i filesystem for Windows from http://www.icdia.org/articles/filesystem.html.
VCD PowerPlayer from CyberLink (http://www.cyberlink.com.tw/) can play CD-i movies directly off of a Green Book disc.
In-depth information is available from http://www.icdia.org/.
Typical Red Book audio CDs don't have this information. Software audio CD players like those provided by Adaptec or Microsoft require you to type in the information, which is then stored in a database on your hard drive. The discs are identified by computing a signature based on track offsets and other fields. http://www.cddb.com/ acts as an Internet database of CD info.
Some newer formats, like CD Extra, allow or even require such information to be included on the CD. See Sony's pages at http://www.cdextra.com/.
Some recent CD players are advertised as "CD-Text Ready". These use the CD-Text data embedded in the P-W subcode channels to display disc and track title data. See section (3-28) for more about CD-Text.
CD-R's have a pre-formed spiral track, and the sector addresses are hard-coded into CD-R media, so there's no flexibility. Every disc holds a predetermined amount of data.
Most discs rated at 74 minutes hold slightly more than that. How much more depends on the brand of media, batch of media, and perhaps even on the recorder used (see section (7-6) for more details on how much a CD-R can hold). In some situations you can exceed the stated capacity of the disc; see section (3-8-3) below.
Since CDs are written in a spiral, the amount of data you can get on a disc is affected by how tightly spaced the "groove" is. A standard Red Book audio CD or Yellow Book CD-ROM is designed to allow at most 74 minutes of data. By using a tighter track pitch on the spiral "groove" on the glass master, manufacturers can get more data onto the disc. In theory this could make it harder for some CD readers to use the discs. See section (3-8-1) for notes on 80-minute discs.
The easiest way to get more data onto a disc is not to try. For audio CDs, you can leave off one or two tracks that you're not overly fond of. For data CDs you may be able to drop some images or sample data. The most common problem people encounter with data CDs is trying to copy them as a collection of files rather than doing a bulk copy of the entire disc. See also section (3-24).
One user suggested using the "speed up" function of SoundForge or CoolEdit to increase the speed of extracted WAV files by 3%. This supposedly gives better results than resampling, and allows writing 77 minutes of audio onto a 74-minute disc.
If you have a mono recording, you could double the length of a CD by recording half the sound on the left track and half on the right. The sound would be recorded as two monaural files, and then merged into a single stereo file with a sound editor like Cool Edit. (With Cool Edit 96: load first mono file. Use "Convert Sample Type" to convert to Stereo. Select the right track, and Delete Selection. Use Mix Paste to load the right track from the second file, or just fire up a second copy of Cool Edit with the other track, and use Copy and Paste commands.) The person playing the CD back will need to use a "balance" knob to select the left or right track. One issue with this method is that the track markers apply to both tracks, so providing random access to specific sections can be tricky.
If you're trying to copy a CD-ROM or VideoCD and running out of room, you may have a different problem. See sections (3-24) and (4-25).
Incidentally, don't get confused when you discover you have 700MB of audio extracted from a CD that only holds 650MB. Audio sectors use 2352 bytes per sector, while standard CD-ROM data uses 2048 (the rest is for error correction). You can put roughly 747MB of audio onto a disc that only holds 650MB of data.
In general, they work just fine. Reports from people who have used 80-minute CD-Rs indicate that compatibility with different CD-ROM drives is very good. However, bear in mind the following statement, which was sent by e-mail from a TDK representative:
"The CD-R80 is a special product developed by TDK to meet the application needs of software developers and music studios. To achieve its 80 minute recording time, track pitch and scanning velocity specification tolerances had to be minimized, reducing the margin of error between drive and media. This means limited compatibility between some CD-Recorders and CD-ROM Readers. If you intend to use this recording length, please check with your hardware manufacturer. Use of the CD-R80 is at one's own risk. No guarantees of performance are made by TDK."Whether it's better to use 80-minute discs or "overburning" (described in the next section) is a worthy subject for debate. Both can cause problems on different CD-ROM drives, and not all recorders are capable of doing one or the other. Because of consumer demand, nearly all recent drives can do both.
An 80-minute disc has roughly 360,000 sectors instead of the usual 333,000. This increases the CD-ROM capacity from 650MB to 703MB.
If you're making backups of your hard drive or writing valuable data, don't use either. Stick to 74-minute blanks, and only record as much as you're supposed to. CD-R media is too inexpensive these days to justify pushing the limits for a slight increase in storage. Long-term reliability is the most important factor in backup media.
Here's a few personal notes on my experiments with TDK 80-minute "green" blanks, back in late 1997. Similar discs are now commonly available in most retailers, often for the same price as 74-minute media. Back then this wasn't the case, but I was able to purchase a small quantity (three discs) from Microboards at http://www.microboards.com/. This is rather outdated now, but I'm leaving it in as a historical footnote.
The discs were part number SCWA-ETC80A-X, priced at US$40.00 per disc in October 1997. That was about 20x the cost for an extra 8% storage. The discs were unbranded. The only difference I could see between these and other TDK green discs is that on the hub it says "CD-Recordable 6129B-80". Easy CD Creator Deluxe v3 showed 359,624 blocks (702.8MB in MODE-1) on the TDK 80-minute blanks, versus 333,010 blocks (650.8MB) available on my Mitsui gold 74-minute blanks.
The first challenge was finding software that would work correctly with the discs. Neither Easy-CD Pro 95 v1.2 nor Easy CD Creator Deluxe v3.0 would allow me to do a test recording with more than 650MB of files. I ended up using mkisofs to create an image file with 341,163 blocks (666.3MB) of data, composed of two large .AVI files, and three smaller pieces of one of the other .AVI files. (With Easy CD Creator Deluxe v3.5 and later, you can choose to ignore a warning about the data size.)
Using a Yamaha CDR-102 with v1.0 firmware, the first thing I tried was to burn the image file to a 74-minute blank. Easy-CD immediately rejected the disc, saying there wasn't enough space. I then put the 80-minute blank in and did a test run. Easy-CD Pro 95 had no problems burning the ISO-9660 image file, until the screen saver activated and McAfee anti-virus "screen scan" kicked in. Good thing it was a test burn; I got a buffer underrun. I killed the screen saver and virus checker and ran again, had a successful test run, and followed it with a successful burn.
To verify the data, I used Easy-CD Pro 95's "compare track" feature. This failed, complaining that one track was shorter than the other. My guess is that the compare feature has some sort of track length limitation. My next attempt was to use the Linux "sum" command to make sure that the disc was readable in my Plextor 8Plex. This worked fine, and the output of "sum" matched what I got on the 4x CD-ROM drive in the Sun workstation at work. I also tried the disc in a Mac 7500 and a Dell Pentium, and had no problems with either.
The next step was an 80-minute audio CD, and that's where things fell apart. Easy-CD Pro 95 v1.2 didn't work at all (!), Easy CD Creator Deluxe v3.0 again refused to allow me to create a long audio CD, and with Jeff Arnold's software (both the DOS version and CDRWIN) the test write failed after a minute or so (after the lead-in had completed?). Strangely, removing the last two tracks from the cue sheet, which reduced it to 72 minutes, allowed the test write to succeed on both 74-minute and 80-minute blanks. It appears that the Yamaha CDR-102 drive is unwilling to write that much audio data.
Small quantities of 90-minute and 99-minute blanks have appeared, but since their introduction in late 2000 they haven't become as commonplace as other lengths. Indications are that many recorders and some software don't really work with the longer discs.
The discs have capacity of roughly 791MB (90 min) and 870MB (99 min). However, all the capacity in the world won't help you if you can't read the disc back. If you're interested in larger but incompatible discs, and don't want to pay the premium imposed by DVD-R, read about DD-R/DD-RW in section (2-37) and ML in section (2-39).
CD time stamps are two digits (binary coded decimal, in case you were wondering), so exceeding 99 minutes isn't possible. You could, in theory, declare there to be 99 seconds in a minute and 99 sectors per second, but that would break just about everything that tried to read one. The limits of the specifications are being pushed at 80 minutes and even harder at 90, so don't expect much more out of CD-R. Some knowledgeable individuals have stated that the longest possible CD-R is 79 minutes, 59 seconds, 74 blocks long, because of the way that the last possible start time of the lead-out is encoded, but you can use "overburning" (discussed in the next section) to write past that point.
See http://www.mmore.com/download/Technical_write-up-MMORE_90_min.pdf for a tutorial on burning 90-minute discs with Nero. In short: make sure your drive supports overburning, set "Enable overburn" in the "Expert features" tab of the preferences, ignore the warnings, and cross your fingers. Always verify the disc afterward.
The capacity of a CD-R is calculated to allow enough space to hold at least 74 minutes of Red Book audio data and 90 seconds of digital silence. The silent area is called the "lead-out", and is included so that a CD player will realize that it has reached the end of the disc, especially when fast-forwarding.
When a recording program tells you the exact capacity of the disc, it's not including the area reserved for the lead-out. There's nothing magic about this reserved area though. With the right kind of setup -- and a willingness to accept write failures as a matter of course -- you can put data into the reserved area, and possibly into a few blocks past the end of it. This is often referred to as "overburning" a disc.
How much more you can fit depends almost entirely on the media. Some brands will hold as much as 78 minutes, but it varies from batch to batch. You can use Feurio! (section (6-1-42)) to compute the maximum size of a specific disc without actually writing anything on it.
You also need the right recorder and the right software. The Teac CD-R55S, Plextor PX-R412C, Yamaha 4xx/4xxx, and Memorex/Dysan CRW-1622 units have been used to write "extra long" audio discs successfully. The Philips 36xx, HP 71xx, and Ricoh 62xx units don't seem to be willing to do so. In some cases, getting the firmware revision may be important. A recorder that isn't able to do this sort of writing will usually reject the cue sheet before writing begins.
To write such a disc, you need to use a program that won't refuse to exceed the disc capacity. Easy CD Creator, in an attempt to prevent you from making mistakes, will refuse to allow you to write more than you should be able to. CDRWIN will warn you that the write may fail, but will allow you to continue anyway. Nero has a preference (under Expert Features) called "enable oversize disc" that allows the longer write.
One approach to determining the maximum disc length is to gather a large collection of audio tracks, and start writing. Eventually the recorder will attempt to write past the end of the disc, and the write process will fail. Now play the disc, preferrably in a player that shows the total elapsed time for the entire disc. When the music cuts off, make a note of the time. That's the absolute capacity of the disc.
Most (all?) CD players will display the total disc time when you first put the disc in. This value represents how much you tried to write, not how much was actually written. If you want to impress your friends, try to write 88 minutes of music. You won't get anywhere near that far on 74-minute media, but the CD player will show it.
It should be possible to write a CD-ROM in the same manner as an audio CD, but the space would have to be calculated so that the write failure occurred when the lead-out was being written. Otherwise, some of the files that appeared to be on the disc wouldn't actually exist.
Recording in DAO mode may be helpful to ensure that the lead-in gets written. Without a table of contents, the disc is useless. It's very likely however that you will be able to finalize the disc even after the write fails.
Depending on the disc and your player, you may have trouble seeking out to tracks near the end of the disc. Also, your CD player may behave strangely when it walks off the end of the disc: one user said he had to open and close the player afterward to convince it that a disc was still loaded.
The disc surface past the end of the area reserved for the leadout may be unreliable. Attempting to use more than 90 seconds (about 15MB of MODE-1 data) beyond the rated capacity of a disc could be asking for trouble.
It's possible to perform similar tricks on 80-minute media. Experiments with TDK 80-minute discs resulted in a recorded length of 82:09. MMC recorders don't seem to like having the lead-out position any later than 88:29:74, but that shouldn't get in the way.
Further commentary and instructions can be found at http://www.cdmediaworld.com/ under "OverSize / OverBurn CD-Rs", including a list of recorders that are known to work and step-by-step instructions for using popular software.
The first thing you have to do is get them onto your computer. There are three basic approaches: use a scanner to convert printed photographs, use a video digitizer to pull images off of a video tape, or use a digital camera to take pictures that can be transferred directly.
There are a great many different scanners, with different resolutions and capabilities. http://www.zdnet.com/special/filters/sc/scanner/ is a fair place to start. (If the link doesn't work, go to zdnet.com and look for reviews of scanners.)
Video digitizers are mentioned in section (3-16). If you're scanning off of VHS video tape, you are going to get disappointing results.
Digital cameras will generally give you the best results. A mid-range digital camera will give you pictures that look as good (when printed on a photo-quality printer, which are inexpensive now) as a 35mm point-and-shoot film camera. A few links:
Once you've got the images in a reasonable state, save them in a widely accepted format such as JPEG or TIFF, and write them to a CD-ROM like you would any other files. You may need to use an "Export" function rather than "Save As...", because consumer photo software authors tend to use proprietary image formats as the default.
If you want to create a PhotoCD that can be played in a PhotoCD player, continue on to the next section. If you're interested in arranging the pictures into an album, see (3-9-2).
First off, you need to be aware that certain aspects of PhotoCD creation are proprietary to Kodak. Programs like Roxio's Easy CD Creator will allow you to create CD-ROMs with PhotoCD image files, and you will be able to view the images with Mac or PC programs that understand the PhotoCD file format, but you won't be able to look at the disc with a PhotoCD player.
http://www.kodak.com/country/US/en/corp/pressReleases/pr19950328-10.shtml has the glossy brochure information, with some Kodak contact information. The Build-It and Arrange-It software, which allow you to create "real" PhotoCDs, costs about US$450. Kodak apparently pulled the software from the market in December 1997, so it may be difficult to find.
http://www.shiresoft.com/ gives you step-by-step instructions and software for creating "real" PhotoCD discs with Kodak's software. The Build-It program will only write to Kodak CD recorders, but a translator available from this web site will allow it to work with GEAR or CDRWIN. Follow the Kodak links on that page.
There are some utilities that will convert images into PCD format, but they only support the uncompressed base resolutions. The higher resolutions are compressed with an algorithm proprietary to Kodak.
There are programs available that will do this for you, or you can take a "do it yourself" approach. Some examples:
Roxio "Photo Relay" (part of Easy CD Creator Deluxe Edition - see section (6-1-26)). According to their web page, it "lets you organize digitized photos and videos, then create Slide Shows, Web Albums and Video Postcards that can be stored to CD and shared with others - no proprietary viewer is required by the recipient!".
Cerious "Thumb's Plus" (http://www.cerious.com/). Helps you organize images and create slide shows. Free evaluation version.
Firehand "Lightning" (http://www.firehand.com/lightning/). Photo albums, slide shows, screen savers. Free evaluation version.
Tlonstruct "CDView Pro" (http://tlonstruct.com/). Fancy picture viewer. Free shareware download.
G&A Imaging "PhotoRecall" (http://www.ga-imaging.com/). Commercial program with lots of features.
InMedia "Slides & Sounds" (http://www.inmediapresents.com/slideshows.html). Create fancy presentations. Demo available.
Extensis "Portfolio" (http://www.extensis.com/portfolio/). Heavy-duty software for "media asset management". Supports every file format you've ever heard of, and has support for hybrid CD recording.
The do-it-yourself approach. Make an HTML page with pictures, using a program like Microsoft FrontPage to create thumbnails (the auto-thumbnail feature is *very* handy), so that when you click on the thumbnail image you get the full-sized image. Put the HTML page and all of the graphics onto a CD-ROM, and view the pictures with a web browser. For bonus points you can use "shellout" with autorun.inf (section (3-21)) to have Windows automatically launch the default web browser when the disc is inserted, and "mkhybrid" to create a disc with long filenames and correct file types for Rock Ridge, Joliet, and MacOS.
The "Film Factory" software that comes with some Epson printers has an "export to web page" function that works pretty well. The "lite" version that comes with their greeting card paper may or may not support this feature.
The easiest way is to use a program that does it for you. Ulead's "DVD PictureShow" will create VideoCD or DVD discs with your photos on them. More information is available at http://www.ulead.com/. A similar product is PictureToTV from http://www.picturetotv.com/.
The first step is to make sure your DVD player can play CD-R media. Create an audio CD on CD-R media, put it into your DVD player, and try to play it. If it works, great. If it doesn't, try the experiment again, this time with CD-RW media. If neither works, or CD-R doesn't work and you can't record CD-RW discs, you're out of luck. See section (2-13) for more about DVD players and compatibility.
The next step is to find a way to display the photos. Some DVD players can display PhotoCD discs, but there isn't a way to create "real" PhotoCD discs with currently available software (see section (3-9-1)).
The alternative is to create a VideoCD with still frames. Each still frame is a medium sized (704x480 in NTSC) JPEG image. By gathering these into a collection, you can create a VideoCD "slide show" that will play on most DVD players. Be careful though: a fair percentage of DVD players do not support VideoCD. You should be able to figure this out by looking through the manual. If no reference to VideoCD can be found, you'll just have to try it and see.
See section (3-16-1) for more about VideoCD.
The MPV (MultiPhoto/Video) specification was announced in November 2002. It's purpose is to define a standard way of storing pictures, videos, and audio on digital media. This should allow you to create discs with multimedia content easily and display them on compatible DVD players. See http://www.osta.org/mpv/.
[ Moved to section (3-35). ]
As always, it depends.
MS-DOS lets you see the first data session. Usually. Win95 lets you see the last data session. Usually. Roxio's Session Selector and Ahead's MultiMounter will let you choose which session you see.
Some CD creation software (e.g. Roxio Easy CD Creator) writes a complete table of contents in each session, some of which refers back to the files from the previous session, allowing a form of incremental backup. (This will work for ISO-9660 discs, but won't work for HFS. However, this is less painful than it seems because a properly-configured Macintosh will let you mount all the sessions as individual volumes.)
Roxio's Easy CD Creator will allow you to combine the contents of several previous sessions by creating a new session (load the file/directory info from more than one session, then write and close a new session with that directory structure).
Some of it depends on the SCSI or CD-ROM driver you have installed. It's unwise to expect somebody else's system to treat multisession discs the same way yours does.
Conversion of cassette tapes and vinyl records is increasingly popular. Common reasons range from plans for long-term preservation to a desire to listen to old favorites while driving in a car without a tape player.
There are two basic kinds of CD recorders: those that attach to a computer, and those that stand alone. The latter, described in detail in section (5-12), are usually connected to a stereo system. They are easier to work with, but less flexible.
The first step, regardless of equipment, is figuring out how to physically connect your tape player, turntable, or wax cylinder player to something else. You almost always want "line-level" sound. The output from a turntable is typically not line-level, so it has to be connected to a receiver or pre-amplifier "phono" input. You then use the outputs from the receiver or amplifier; if you can find outputs labeled "tape out" or "preamp out", use those.
(A pre-amplifier raises the voltage level from the phono cartridge up to "line level" voltage. An amplifier increases the signal from line level to whatever is needed for your speakers. A pre-amplifier will also compensate for pre-emphasis in the recorded material.)
You could connect your recorder to the headphone jack on the receiver or amplifier, but that's not the best way to go. The voltage level coming out of the headphone jack varies on the volume setting, while line-level output doesn't. This makes line-level easier to set up. If all you can find is a headphone jack, you will have to fiddle with the volume control until the sound is as loud as possible without "clipping". If one of your devices has little colored bars that bounce up and down according to how loud the sound is, you need to play something "loud" on your tape player or turntable, and adjust the volume until the loudest parts rise up just shy of the maximum.
Connect the output from your tape player, receiver, or amplifier into the CD recorder (if you have a stand-alone model) or the "line in" on the sound card on your computer (if you're using that). Continue with section (3-12-1) if you have a stand-alone model, section (3-12-2) if yours is attached to a computer.
You can find odd bits of hardware that will play or enhance playback of older recording formats (78's, LP's, 16" Radio Transcriptions) at Nauck's Vintage Records (http://www.78rpm.com/).
For those of you wondering what the deal with pre-emphasis is, this little tidbit is courtesy Mike Richter:
"Preemphasis has been used since the earliest days of commercial recording. In general, the high-frequency content of the music (or whatever) being recorded is low and the noise is high. Therefore, treble was boosted and lows were cut by a preemphasis curve which was removed in playback. The standard RIAA curve for turnover and rolloff (the amount and frequency for treble and bass, respectively) was not accepted universally until the 50's, and some fine preamps offered selectable values with presets for the common curves into the early transistor era."
Once you've got everything hooked up, hit "record" on the CD recorder and "play" on the other device. Wait a while. You're done.
You may want to fiddle with it to mark the start individual tracks. See the instructions that came with your recorder.
Recording into a PC is a little trickier, but you have much more control over the final result. It's easy to edit away silence and reduce or remove clicks and hissing.
In addition to the material here, you may want to read one or more of these tutorials:
http://www.blazeaudio.com/howto/lp-overview.htmlThe page at http://www.octave.com/library/audiocd.html is also useful.
The most crucial component is the sound card. The sound card converts the audio signal from analog to digital (an "A/D conversion"). Some cards do this conversion better than others. You can use the A/D converter built into a sound card like a SoundBlaster 16, but the sound quality will not be very good. The sound cards from Turtle Beach (Tropez, Tahiti) and CrystaLake are a step up, and a Digital Audio Labs CardD+ is about as good as it gets for internal A/D cards. If you're really serious, you should get an external A/D converter like the Symetrix 620 or the Lucid AD9624 and feed the digital output from that into the computer. (Looks like the Lucid device has superseded the Symetrix one -- it's the same company. Relevant URLs are http://www.symetrixaudio.com/ and http://www.lucidtechnology.com/.) Other products can be found at http://www.midiman.com/.
Another way of accomplishing the same thing is to record to an audio DAT deck and then use the digital output on the DAT recorder; see section (3-13) for details. With some decks, such as the TASCAM DA-20 mkII and DA-302, it's not even necessary to record to tape. You can play straight through the recorder.
A problem with some sound cards (really cheap Opti and ESS cards have been named) is that the crystal that controls the recording sample rate is off. If the card doesn't do the sampling at the correct rate, the recorded audio may end up slightly slower or faster than the original. This will become apparent when the sound is played back off of a CD or through a better sound card. Most sounds cards don't have this problem.
If you have questions or need a recommendation on a sound card, you might want to try:
news:rec.audio.techSome highly technical benchmark evaluations of cards are available at http://www.rockpark.com/soundcards/ and http://www.pcavtech.com/.
Roxio's Easy CD Creator (section (6-1-26)) includes an application called "Spin Doctor" that performs most of the tasks needed to transfer LPs to CD. Depending on your needs, it may provide a simple all-in-one solution.
A simpler approach is to use a program capable of recording large amounts of audio from the sound card. Cool Edit 2000 (section (6-2-14)) works nicely. Whatever you choose, you should again play a loud passage and watch the "VU meter" display to make sure you're getting as much signal as you can without clipping. If the little colored bars are slamming against the top, you're clipping. The Windows volume control panel (double-click on the yellow speaker icon in the lower-right-hand corner) has a VU meter in it, and allows you to set the input gain.
Configure the application to record 44.1KHz 16-bit stereo sound, click "record", hit "play" on your tape player or turntable, and wait a while. When the music is done, stop the recording on the computer. You can either record the result directly to a CD, or clean it up a bit first. See the next section for some suggestions.
Bear in mind that CD-quality audio uses up about 10MB of disk space per minute, so one side of a 45-minute tape will require roughly 450MB. Make sure you have enough disk space before you start.
There are a variety of programs that can automatically remove pops, clicks, and hissing from digitized audio. Few automated tools can do as good a job cleaning up pops and other noise as an experienced person, however. If you want to perform the transfer by hand, the following method has been suggested for PC users with Cool Edit:
Software that may come in handy:
Don't forget that CD audio is 16-bit PCM stereo samples at 44.1KHz, and will chew up disk space at roughly 176K per second. Playing back large sound files is difficult with simple-minded applications like the standard Win95 sound player, because they try to load the entire file into memory all at once. Cool Edit 2000 is able to play files back as it reads them, and works very well even over a network. (Section (4-20) has some other suggestions on this same topic.)
See section (3-3) for some tips on avoiding clicks when committing the audio to CD.
If, for some reason, you'd like to record "live" to the CD-R instead of recording to the hard drive first, see section (3-54).
Buy a card that will allow you to go from DAT to hard disk digitally. Make sure you get one that can handle the same digital standard the DAT recorder uses, i.e. S/PDIF (Sony/Philips Digital Interface Format, sometimes referred to as "domestic") or AES/EBU ("professional").
Some of the solutions for the PC are:
Visit http://www.digitalexperience.com/cards.html for a feature comparison of many different models.
An inexpensive S/PDIF card available from Computer Geeks (http://www.compgeeks.com/) was evaluated by some newsgroup readers in mid-1998. Apparently there were some problems with the physical dimensions of the card (too wide for some PC slots), the documentation is poor, and the voltage level for both input and output was TTL instead of standard S/PDIF. You're probably better off with one of the established brands unless you're sure about what you need.
For technical information on S/PDIF, check out http://www.plompy.co.uk/music/digital_audio.html#cmedia.
You should record from the DAT onto your hard drive, and then record the CD from there. If you try to record directly from DAT you'll likely end up with a lot of wasted CD-Rs due to buffer underruns or minor mistakes. You should use Disc-At-Once recording for best results.
One issue you need to be aware of is that some older DAT recorders can only record at 48KHz, while CDs are recorded at 44.1KHz. If this is the case with your equipment, you will have to do a sample rate conversion. The DSP on cards like the ZA2 will do this for you, or you can use an audio editing program like Cool Edit or Sound Forge.
There *are* CD-R drives that have analog inputs, and can record directly from audio sources. See section (5-12).
If you use a DAT and haven't been to the DAT-heads home page, you should definitely check out http://www.atd.ucar.edu/rdp/dat-heads/.
If you want to manipulate audio DATs directly from your computer, you need a DDS drive with special firmware. The SCSI DDS drives that are typically sold for backups don't have the firmware required to handle DAT tapes. Most SGI workstations can do this, and Mac users should check out http://www.demon.co.uk/gallery/StudioDAT.html [link dead?]. If you have an Archive Python DDS drive, check out http://www4.informatik.uni-erlangen.de/~eckert/. Reputable Systems (http://www.reputable.com/) sells DDS-2 drives with SGI firmware, Archive/Conner/Seagate model CTD-8000HS.
Some other drives can be supported with appropriate firmware updates. See http://www.trygve.com/playaudiodat.html.
An interesting combination of technologies is the DAT-Link, formerly available from http://www.tc.com/. It connects to the digital connectors on the DAT machine (or MD, DCC, or CD player) and the SCSI interface on a computer. The device can be controlled from other computers on a network.
If you're interested in mastering production audio CDs, you should take a look at http://www.sadie.com/.
There are two ways to do this. The first is to put the data on track 1 of the CD, and audio on the next several tracks (discs created this way are referred to as "mixed-mode" CDs). The CD-ROM drive will automatically look at track 1 and ignore all other tracks, so you'll be able to get at the data and -- depending on the operating system -- will be able to play the audio tracks. Remember that all of the tracks, both audio and data, need to be recorded in a single session. See section (3-2).
The down side of this is that audio CD players may attempt to play track 1, which can be obnoxious or downright harmful to audio equipment. Most modern CD players are smart enough to ignore data tracks, so this won't usually be a problem.
The other approach is to create a multisession disc with the audio tracks in the first session and the data track in the second. This is how CD Extra (the format formerly known as CD Plus) works. Audio CD players only look at the first session, and CD-ROM drives are (supposed to) start with the last session, so it all works out. Sony Music has some pages at http://www.cdextra.com/.
(NOTE: it appears that in some situations a Macintosh will not handle multi-session audio/data CD-R discs correctly. For example, a G3 with a DVD-ROM drive running Mac OS 8.6 works fine, but a G4 or iMac running Mac OS 9 will reject the disc as unreadable. The same system will handle pressed discs correctly -- only CD-Rs fail. The reason for this is uncertain, but it may be possible to work around it by disabling the system's audio CD extension when you want to read the data portion.)
A common question is how to write the audio in the first session without gaps between tracks, because you can't use disc-at-once recording. (If you did use DAO recording, the disc would be closed, and you wouldn't be able to write the data track). With the right hardware and software, you can do "session-at-once" recording to write the audio without gaps. For example, if you're recording with Nero and SAO-capable hardware, you just select disc-at-once mode but don't select "finalize CD".
What happens when you try to play one of these as audio in your CD-ROM drive? As with most things multisession, it depends on your drive. (The player that comes with Plextor CD-ROM drives does the right thing. If you're using a different drive, you're on your own.)
There's actually a third way to do this that involves putting the data track into the extended pregap of the first audio track. Instead of the audio starting at minute:second:block 00:02:00, the data starts there, and the audio is written after. The pregap is adjusted accordingly. This method never gained popularity because some drives started playing at 00:02:00 regardless. There doesn't seem to be a way to do this on CD-R.
Some CDs perversely put audio in the pregap. You can play it by starting to play track 1, then holding the "reverse" button until it seeks all the way to the start of the disc. Some older digital audio extraction programs would just ignore the "hidden" audio, but most newer ones will extract the entire track.
For example, _Factory Showroom_ by "They Might Be Giants" looks like this:
See section (3-36) for more information on "hiding" audio tracks.
On a Mac, this is reasonably straightforward. A CD can be bootable if it has a bootable system folder on it. Tell the recording software that you want to make the CD bootable; this usually involves clicking in a checkbox before burning the first session. Then, copy a bootable system folder onto the disc. An easy way to create an appropriate system folder is to launch the system installer, tell it you want to do a "Custom" install, choose the "Universal System" option, and then install it onto the CD source volume. One caveat: any control panels or extensions that want to write to their preferences files will fail. You may need to write from a system folder that has been booted at least once.
Detailed instructions for creating a bootable CD with Toast can be found at http://www.roxio.com/en/support/toast/toastbootable.html.
Holding down the 'c' key while booting will cause the Mac to boot from an internal CD-ROM drive. Alternatively, the "Startup Disk" control panel will allow you to select a CD-ROM.
The rest of the section applies only to PCs, which are more challenging.
The BIOS or SCSI card on most newer machines support booting from CD-ROM, but on many older machines it's just not possible. Phoenix (the BIOS developer) and IBM have created the El Torito standard for doing this sort of thing. When the machine boots, if the BIOS recognizes a bootable image on the CD-ROM, it maps that image onto the A: floppy drive. (Depending on implementation, A: will move to B: and B: will go away.) From that point onward, it's just like booting a floppy.
Not surprisingly, the way you create a bootable CD-ROM is to take an image of a bootable floppy disk and write it in a specific way onto the CD. Many of the current CD writing programs, including Easy CD Creator and CDRWIN, will do the hard work for you.
A very nice page with lots of technical and how-to information:
http://www.nu2.nu/bootcd/You can find El Torito specifications and a "how to" guide at:
http://www.phoenix.com/products/specs.htmlIf you like to do things the hard way, step-by-step procedures with varying levels of detail can be found here:
http://www.cdpage.com/Compact_Disc_Variations/bootablecdarticle.htmYou can learn how to make bootable Win95b/Win98 CD-ROMs here:
http://www.heise.de/ct/Service/English.htm/99/11/206/When booting the PC, you may need to change the boot order in the BIOS from the typical "A, C" to "A, SCSI, C", and configure the SCSI interface to attempt to boot from CD. On some adapters, the boot-up SCSI bus scan may take an extra second or two while the interface tries to determine if a bootable CD-ROM is present.
Some programs insist that bootable CD-ROMs be written in plain ISO-9660 format, not Joliet. One way around this is to write the bootable portion in the first session, and then write the rest of the data in a second session. However, not all PCs will boot a multisession disc. A better approach is to use a program like mkisofs (6-1-10) to create the image.
The El Torito standard allows CD-ROMs to have more than one bootable image, but few applications support creating such images. You can use mkisofs with the "-eltorito-alt-boot" option to do this.
If you're having trouble finding drivers for your CD-ROM drive, try the Win98 boot disk, or http://www.drivershq.com/.
This topic is largely outside the scope of this FAQ, so I'm not going to go into much depth. The Usenet newsgroup news:rec.desktop.video is more applicable. I'm not aware of an FAQ for that group, but the links found at http://www.videoguys.com/jump.htm will get you started.
You need a capture device to transfer the video to your hard drive. Capturing high-quality video can eat up 2MB or more per *second* of video at full resolution (640x480x24 at 60 fields per second for NTSC) with a reasonable degree of compression, so this isn't something to be undertaken lightly. The lower your quality requirements, the lower the bandwidth requirements. On a fast machine, you can even get away with just a TV tuner card, using the software from http://www.winvcr.com/.
If MPEG is your only interest, you might be better off with an MPEG-only card rather than a hobbyist video capture board. http://www.b-way.com/ and http://www.darvision.com/ are good places to look. The Broadway card has been given high marks for quality.
Once you've captured the video, you'll probably want to edit it, at least to clip out unwanted portions or add titles. Packages for doing this, like Adobe Premiere and Ulead MediaStudio, are usually included with the capture card. These will also let you adjust the resolution, color depth, and compression quality to output the video so that it's suitable for playback on double- or quad-speed CD-ROM drives.
You can convert AVI files to MPEG and vice-versa with a program from Ulead (see http://www.ulead.com/), Xing Technologies, or several other vendors. You should be able to create QuickTime or AVI movies using the compression codec of your choice from the video editing software. A good choice is TMPGEncoder, from http://www.tmpgenc.com/e_main.html.
Once created, you can write the AVI, MPEG, or MOV (QuickTime) file to a CD-ROM like you would anything else. If you'd like to view the disc in a DVD player or other VideoCD playback device, read the next section. Note that not all DVD players are capable of reading CD-R media, so if VideoCD on CD-R playback is important to you, check the DVD player feature set before you buy.
Converting directly to DVD format is pretty reasonable now, with relatively inexpensive DVD-R recorders and authoring software. Some Macintoshes ship with iMovie/iDVD and a DVD recorder built in.
The MPV (MultiPhoto/Video) specification was announced in November 2002. It's purpose is to define a standard way of storing pictures, videos, and audio on digital media. This could eventually be the preferred way to store movies on a disc. See http://www.osta.org/mpv/.
This section assumes you already have the video captured on the hard drive of your computer. If you don't know how to do that, read the previous section.
The goal is to create a White Book VideoCD, which can be viewed on any VideoCD-compatible playback device. Most PCs and Macs have some amount of support, as do many DVD players, so even if you can't find a dedicated VideoCD player or CD-i box you should be able to find a way to watch them.
VideoCDs can only be read by CD-ROM drives capable of reading CD-ROM/XA discs. If your drive doesn't claim to support PhotoCD, you're probably out of luck, but this is rare. Microsoft's ActiveMovie (now Windows Media Architecture) and Apple's Video Player can play movies off of a VideoCD. Depending on the software you have installed, you may get a nice player, or you may need to examine the disc manually and open the ".dat" files in the "mpegav" directory.
If you were hoping to play your VideoCD on a DVD player, you should read about VideoCD and CD-R/CD-RW compatibility with DVD players first. See http://www.dvddemystified.com/dvdfaq.html#2.4.5 and section (2-13).
CD-R software packages like Easy CD Creator, Nero, and GEAR can write MPEG-1 movies onto a CD in the necessary format. You have to be careful when creating the MPEGs, because if the encoding parameters (frame rate, number of pixels, etc) don't match the VideoCD parameters you may have trouble getting the CD writing software to accept the movie.
You can include still frames from JPEG images as well. Most VideoCD creation software provides a way to organize "assets"
John Schlichther's "avi2vcd" combines standard tools into an easy-to-use program for Win95 and NT. You can use it to convert an AVI file into a VideoCD-compatible stream. http://www.mnsi.net/~jschlic1/.
Another choice is TMPGEncoder, from http://www.tmpgenc.com/e_main.html.
If you're running Linux you should take a look at Bernhard Schwall's "avi2yuv" program. It converts M-JPEG movies created with popular video capture boards into a format accepted by the Berkeley MPEG-1 and MPEG-2 encoders (ftp://bmrc.berkeley.edu/pub/mpeg/). The README for avi2yuv lists the additional software packages (all of which are free and run under Linux) needed for creating MPEG movies complete with sound. Most (all?) of the utilities can also be built to run under DOS. http://sunsite.unc.edu/pub/Linux/apps/graphics/convert/.
"iFilmEdit", from http://www.cinax.com/Products/ifilmedit.html, will convert MPEG to VideoCD, and can reportedly convert a VideoCD .DAT file back into a plain MPEG file.
"VCDGear", from http://www.vcdgear.com/, converts between .dat and .mpg.
http://www.vcdhelp.com/ has software and information.
The "VideoCD Cook Book" at http://www.flexion.org/video/VideoCD/0.html is worth a look.
Easy CD Creator, as of v3.x, requires that an MPEG MCI driver be installed in the system (unlike CD Creator, it doesn't come with Xing's MPEG software). The popular VMPEG 1.7 doesn't quite work: ECDC can't see the audio, and you're not allowed to select the frame to view when shuffling streams around. If you have VMPEG installed as the MCI driver -- select "About ECDC" from the Help menu to check -- you need to *remove* VMPEG and then install ActiveMovie. (I removed under Win95 it by going into the Advanced section of the Multimedia control panel, expanding "Media Control Devices", selecting vmpegdll, and clicking on "Remove", but you may be able to use Add/Remove Programs instead.) ECDC v3.x was very picky about the video streams; v4.02 is much better.
Finally, you should be aware that MPEG playback is rather CPU intensive, and it's possible to create movies that don't play very well on slower machines (90MHz Pentium, 68K Macs) without hardware support. Machines built in 1997 or later shouldn't have trouble.
First, read about creating a VCD in section (3-16-1).
Next, read http://www.uwasa.fi/~f76998/video/svcd/overview/.
The links near the end of the document point to some pages with SVCD authoring instructions. Programs such as Nero Burning ROM (6-1-28) and Enreach I-Author (6-1-61) are able to create such discs.
Some discs have been produced that call themselves "AVCD", as in audio-video CD. For example, Kylie Minogue's "Fever" CD was released as a two-disc set in Asia. Disc one was the "Fever" audio CD, disc two had four VideoCD video tracks and five bonus audio tracks.
If you put disc two into a CD player, you would hear nothing for track 1 (which holds the VideoCD filesystem) or tracks 2 through 5 (the video data). If you fast-forwarded to track 6, you would hear music.
If you put disc two into a VideoCD player or compatible DVD player, you would be treated to the first video track. By skipping forward you could get to the later video tracks and eventually play the audio tracks.
This makes perfect sense until you try to figure out how the same audio track is being played on a CD player and on a VideoCD player. If you try to create a VideoCD with extra audio tracks, the VideoCD player will not find them.
The trick used by the AVCD publishers is to encode the audio tracks twice. The songs are present both as Red Book CD audio tracks and as VideoCD compressed audio. A directory called "CDDA" holds files with names like "AUDIO06.DAT" that contain compressed audio. Unlike the video tracks, these don't actually correspond to tracks on the disc.
To create such a disc, you would need VideoCD authoring software capable of incorporating audio tracks. You could then record the VideoCD while leaving the session open, and append the audio tracks using track-at-once recording. Better results would be obtained by writing the video and audio tracks with disc-at-once recording, but that might require a greater level of VideoCD support than most recording applications currently provide.
See section (3-16-1) for more tips on VideoCD.
You can if you have several CD-R drives and the right software. Two examples are CD Rep from Prassi Software (section (6-1-21)) and DiscJuggler from Padus (section (6-1-27)).
Both products are SCSI multiplexors. You use your existing CD writing application (such as Easy-CD Pro 95) like you normally would, and the program sends the same commands to each of the CD-R drives. There are a number of limitations, notably that all devices must use the same command set and may need to have the same firmware revision. There may also be limits on the number of drives you can have attached at once.
DiscJuggler bills itself as "the professional CD Duplicator", CD Rep as "the ultimate professional recording solution". If you're interested in either of these, you should read the web pages for both, and compare the features available.
There are several hardware-based solutions to this, including CD-R units that support daisy-chaining, and control units that vary from the simple (a handful of units wired together) to the complex (robotic arms to move discs around). Most cost more than a Hyundai.
See http://www.cd-info.com/CDIC/Technology/CD-R/duplication.html for an overview of several different hardware solutions, or visit a vendor web page like http://www.princetondiskette.com/.
The following was part of an e-mail message from Jeff Arnold back in mid-1997:
"I do not recommend making "copies of copies" with SNAPSHOT. The reason this does not always work is because many CDROM readers do not perform error correction of the data when doing raw sectors reads. As a result, you end up with errors on the copy that may or may not be correctable. When you make a second-generation copy of the same disc, you will make a disc that has all of the errors of the first copy, plus all of the new errors from the second reading of the disc. The cumulative errors from multiple copies will result in a disc that is no longer readable."This initially generated some confusion, so further explanation is needed. The heart of the problem is the way that that the data is read from the source device. When a program does "raw" sector reads, it gets the entire 2352-byte block, which includes the CD-ROM error correction data (ECC) for the sector. Instead of applying the ECC to the sector data, many drives just hand back the entire block, including any errors that couldn't be corrected by the first C1/C2 layer of error correction (see section (2-17)). When the block is written to the CD-R, the uncorrected errors are written along with it.
The problem can be avoided completely by using "cooked" reads and writes. Rather than create an exact duplicate of the 2352-byte source sector, cooked reads pull off the error-corrected 2048-byte sector. The CD recorder regenerates the appropriate error correction when the data is written.
Some drives and some software will error-correct the 2048 bytes of CD-ROM data read in "raw" mode. This limits the risk of generation loss to errors introduced in the ECC bytes. If the software also regenerates the ECC, it is effectively emulating "cooked" reads and writes in "raw" mode.
This begs the question, why not just use cooked writes all the time? First of all, some older recorders (e.g. Philips CDD2000 and HP4020i) didn't support cooked writes. (Some others will do cooked but can't do raw, e.g. the Pinnacle RCD-5040.) Second, not all discs use 2048-byte MODE-1 sectors. There is no true "cooked" mode for MODE-2 data tracks; even a block length of 2336 is considered raw, so using cooked reads won't prevent generation loss.
It is important to emphasize that the error correction included in the data sector is a *second* layer of protection. A clean original disc may well have no uncorrectable errors, and will yield an exact duplicate even when copying in "raw" mode. After a few generations, though, the duplicates are likely to suffer some generation loss.
The original version of this quote went on to comment that Plextor and Sony CD-ROM drives were not recommended for making copies of copies. The reason they were singled out is because they are the only drives that explicitly warned about this problem in their programming manuals. It is possible that *all* CD-ROM drives behave the same way. (In fact, it is arguably the correct behavior... you want raw data, you get raw data.)
The final answer to this question is, you can safely make copies of copies, so long as the disc is a MODE-1 CD-ROM and you're using "cooked" writes. Copies made with "raw" writes may suffer generation loss because of uncorrected errors.
Audio tracks don't have the second layer of ECC, and will be susceptible to the same generation loss as data discs duplicated in "raw" mode. Some drives may turn off some error-correcting features, such as dropped-sample interpolation, during digital audio extraction, or may only use them when extracting at 1x. If you want to find out what your drive is capable of, try extracting the same track from a CD several times at different speeds, then do a binary comparison on the results. PC owners can use the DOS "FC" command to do this, as described in section (3-3).
It's worth noting that the C1/C2 error correction present on all types of CDs is pretty good, so it is entirely possible to make multi-generation copies with no errors whatsoever. The "cooked" approach for CD-ROMs just happens to be safer.
The easiest way is to use your favorite compression or encryption utility and process the files before putting them on the CD. However, this isn't transparent to the end user.
CRI-X3 enables programs like DoubleSpace to work on a CD. It's intended for a publisher or for significant internal use, and the licensing is priced accordingly. See http://www.cdrominc.com/. (Side note: the company filed patent infringement suits against Traxdata and CeQuadrat in Sep 1998 for distributing CD compression software. This might account for the dearth of similar applications.)
A straightforward solution is to write all of the files onto the disc as .ZIP files, and then use ZipMagic (formerly ZipFolders) to view the contents. It can be found at http://www.ontrack.com/zipmagic/.
PGP at http://www.nai.com/ (was http://www.pgp.com) has some good encryption software, but none of it seems directly applicable to software distribution. PGPdisk, available for the Mac, might be useful but it isn't clear whether it can be used to distribute CD-ROMs.
ScramDisk, from http://www.scramdisk.clara.net/, writes files into encrypted "containers" on disk. It can be used with CD-ROMs, runs under Win95 and Win98, is free, and even includes source code.
http://www.c-dilla.com/ had information on CD-Secure 2, which allowed publishers to distribute network-licensed or "pay for the parts you need" products, and CD-Compress 2, which provides a way to compress data transparently on production CDs. The company is now part of Macrovision.
EnCrypt-CD encrypts the blocks as they are written to CD. It's a shareware product, available from http://www.shareit.com/programs/102046.htm.
Encrypted Magic Folders from http://www.pc-magic.com/ claims to transparently encrypt data as it's being used. Whether it would work from a CD-ROM isn't stated.
http://cd-lock.com/ offers Blowfish encryption and scrambled filenames. End users don't need to install software to decrypt the disks if they're running Win2K or WinXP. (Appears to be related to pc-magic.com, above.)
You can install a cryptographic filesystem (called "CFS") under Linux; see http://www.linuxdoc.org/HOWTO/Security-HOWTO-6.html#ss6.10. Create a crypto-fs, copy your data onto it, then use mkisofs with Rock Ridge extensions enabled to create an ISO-9660 disc image of the encrypted data. Burn the image to CD-ROM.
You may be able to use E4M, from http://www.e4m.net.
BestCrypt, from http://www.jetico.com/, lets you create encrypted virtual volumes in a file that can be stored on CD-R media.
You can get PC Guardian's CD-ROM encryption from http://www.pcguardian.com/.
WinDefender, available from http://www.RTSecurity.com/products/windefender, provides transparent CD-ROM encryption from Windows.
Dynamic-CD can encrypt and password-protect CD-ROMs. See http://www.phdcc.com/dynamic-cd/.
Yes. See section (6-7) for software.
Of course, it's not really necessary to use special software if you're just backing up your data files. Most CD creation programs will allow you to copy arbitrary files onto CD-ROM, and by using the Joliet standard or the UDF filesystem you can preserve long filenames. Unfortunately, if you're not using packet writing, the individual files may show up as read-only under DOS and Windows, so write permission must be re-enabled by hand when the files are restored. With packet writing applications like DirectCD or PacketCD, the correct file permissions are maintained.
(See section (3-57) for instructions on clearing the read-only flag.)
One thing to be careful of on Windows-based PCs: most programs that put files on CD don't preserve the *short* file names that are automatically generated for files with long file names. This presents a problem because the short form is often stored in the Registry and INI files instead of the long form (try searching your Registry for "~1"). When your system is restored, it may not be able to find the files anymore.
A way to work around this is to use a backup program that understands only the short filenames, and save the long ones with LFNBK. A program called DOSLFNBK at http://www8.pair.com/dmurdoch/programs/doslfnbk.htm may be more convenient than LFNBK.
Is CD-R better than, say, DDS-3 tapes? Maybe. Tape formats like DDS and DLT hold considerably more than a CD-R, but because the drives are streaming rather than random access, recovery of a specific file can be slower. For backing up a large system or network, tapes are more convenient. For making backups of a small system, especially one where access to older versions of files is frequently desired, CD-R is the better choice.
Some people prefer CD-RW. For daily incrementals, CD-RW makes sense. For weekly or monthly full backups, you probably want to retain the discs in case file corruption or deletion goes unnoticed for some time.
The longevity of magnetic tape is well understood (around 15 years for most formats). The longevity of CD-R is a little harder to quantify. See section (7-5) for details.
This can get surprisingly involved on a PC. The next few sub-sections go into detail. For a Mac, the answers are pretty simple:
You can use the Macintosh equivalent of Autorun (QuickTime 2.0 Autostart) to automatically launch an application or document on the Mac. The "-auto" flag of mkhybrid (6-1-32) lets you specify this.
Changing the icon on the Mac can be done by using Toast to record a disc image (record by "Volume" instead of "Files and Folders"). Change the icon on the disc image file from the Command-I window in the Finder, then record it.
The "autorun" feature of Windows 95 and later allows a program to be executed right after a CD-ROM is inserted. For this to work, the system must have autorun enabled, and Auto Insert Notification ("AIN") must be turned on for the CD-ROM drive. See section (4-1-1) for more information on AIN and the use of "TweakUI" to modify settings. It may also be necessary, in some configurations, to close the last session on the disc, or AIN will not work.
When preparing a CD-ROM for Windows, put a text file called "autorun.inf" in the root directory that contains something like this:
[autorun]When inserted, the CD-ROM will be shown in the "My Computer" window with the specified icon. If the disc is inserted on a system with AIN and autorun enabled, the program named on the "open" line will be launched.
Icons must be in Windows icon or bitmap format. You can't use a GIF or JPEG. Make it square, 32x32 pixels. If you're going to be doing a lot of these, you may want to try Axialis "IconWorkshop", from http://www.axialis.com/axicons/.
There doesn't appear to be a way to specify custom icons for individual folders.
Incidentally, the "root" directory is the top level of the disc, e.g. "D:\". (If you viewed a directory hierarchy as a tree growing upward, the topmost directory would be at the root of the tree.)
Here's a more complicated example:
[autorun]Taking it line by line, this says:
open = setup.exe /i
icon = setup.exe, 1
shell\configure = &Configure...
shell\configure\command = setup.exe /c
shell\install = &Install...
shell\install\command = setup.exe /i
shell\readme = &Read Me
shell\readme\command = notepad help\readme.txt
shell\help = &Help
shell\help\command = winhlp32 help\helpfile.hlp
If you'd rather not have to deal with all this, try one of the applications listed in section (3-21-3).
In the past it was recommended to use the "start" command, e.g. "open=start index.htm". However, "start.exe" doesn't exist in the Windows NT family (NT4, 2000, XP).
You can launch documents with Windows Explorer on any version of Windows, like this:
[autorun]However, it appears to ignore your browser settings. So, even if you've chosen to make Netscape or Opera your web browser, it will still open the HTML file with Internet Explorer.
An alternative to "start", called "shellout", is available from the "files" section on http://www.mrichter.com/. This is a trivial launcher that you copy onto a disc and use like this:
[autorun]It appears to avoid the above problems, is only 20K, and is free.
For more information on autorun:
http://www.microsoft.com/msj/defaulttop.asp?page=/msj/0499/win32/win320499top.htmInstructions for making a VideoCD autoplay under Windows can be found at http://navasgrp.home.att.net/tech/autoplay_vcd.htm.
Some simple, configurable autorun applications (launchers and menus) are available, most as shareware:
The easiest way is to compare the original with the copy. Some programs, such as recent versions of Nero, will automatically compare the disc contents with the original files. You can also use something like CD-R Verifier from http://www.cdrom-prod.com/cd-r_verifier.html or CDCchedk from http://Fusion.zejn.si/ to check the contents of an entire CD-ROM easily.
Another way is to do a recursive file-by-file comparison. Programs that compute CRCs on files and then compare them (often used for virus-checking) will work.
One way to do this is with use the UNIX "diff" utility, which is available for Windows (along with many other similar utilities) from http://www.reedkotler.com/. If you had copied the contents of C:\MyData onto a CD-R at E:\, you would use:
diff -q -r C:\MyData E:The "-q" flag tells it to report if the files differ, but not show what the differences are, and the "-r" flag says to descend into directories recursively.
There are many other options. A utility called "treediff", available from the Simtel archives (http://www.simtel.com/), may be helpful. http://www.funduc.com/directory_toolkit.htm has a shareware program with some relevant features. http://www.araxis.com/ has an evaluation copy of PMdiff, available for Windows and native OS/2. You can get "FileSync" from http://www.fileware.co.uk/.
You can also use Microsoft's WinDiff, which -- unlike some of the programs mentioned earlier -- understands long filenames. It can be found on Microsoft's recent operating system discs, e.g. on Win98 it lives in \tools\reskit\file\windiff.exe. It used to be available for download from ftp.microsoft.com, but they rearrange that site frequently, so there's not much point in including a URL.
An alternative to windiff is xdiff, from http://www.wookie.demon.co.uk/xdiff/.
Rocksoft Pty has a product called Veracity (http://www.veracity.com/) that can check the integrity of a directory tree.
Visit http://www.fuw.edu.pl/~jt/cdvfy/ for some shell scripts that will compute MD5 checksums on a tree. Under Windows, try Advanced CheckSum Verifier from http://www.irnis.net/ for MD5 and CRC32, or md5summer from http://www.md5summer.org/.
If you *really* want to verify your discs, try http://www.audiodev.com/.
For playing Karaoke and CD+G:
See http://magicland.com/karaoke/drives.htm for a list of CD-ROM drives compatible with Karaoke CDs, and check the CloneCD page for a list of recorders that support "raw" reads and writes.
You don't. The CD-ROM doesn't actually have that much data on it. Some CD publishers use a trick where they reference the same spot on the disc several times with overlapping files. If you try to do a file-by-file copy from the disc onto your hard drive, you'll end up with several copies of the same blocks, and more data than can fit on a CD-ROM.
VideoCDs often appear to have individual files that are 700MB or more. In this case, they really *are* that big. They're written in a special format (CD-ROM/XA Mode-2 Form-2) that drops error correction in favor of more space. This works fine for video data, but is definitely not recommended for ordinary data.
If you want to duplicate a CD-ROM, you should use a program meant for the purpose (CloneCD, CDRWIN, etc). Some software is more capable of dealing with complex CDs than others, so if you have a particular kind of CD in mind (such as VideoCD) you should check the capabilities of the software before making a purchase.
There are a large number of companies that will do modest production runs of pressed CDs, but listing them is beyond the scope of this FAQ.
Do a web search on "CD duplication" and "CD replication", or check out http://www.cd-webstore.com/BurningIssues.html (a licensed-access web site from the www.cd-info.com folks).
Sometimes a disc submitted for duplication will be rejected due to E32 (uncorrectable) errors. If you have a disc rejected, make sure you are using disc-at-once recording mode -- the gaps left between tracks by track-at-once mode are sometimes interpreted as errors. If the problems persist, try changing to a different kind of media, or even a different recorder.
Most CD recorders are capable of doing this, given the right software. The key is to use disc-at-once recording instead of track-at-once.
Some programs give you a great deal of control. Golden Hawk's CDRWIN (6-1-7) will let you specify the gap size for each track, down to zero, and set the location of the track and index marks. You can put each track in a separate file or have the entire recording in a single file. Other programs, like ECDC (6-1-26), are easier to use but less flexible.
You will almost certainly need to use disc-at-once recording. Most drives insist on inserting a two-second gap between tracks when track-at-once recording is used, and those that don't will at best leave an instant of silence between tracks. You can eliminate the gaps from a TAO recording by putting the entire CD into one track, but then you lose the ability to seek immediately to the start of a song.
Most PC and Mac software support both TAO and DAO recording modes. It's prudent to check the web pages before you buy.
If you want to break up a long recording into several WAV files (one per track), it's important to split tracks on precise 2352-byte boundaries. If you don't, you'll get tiny periods of silence or noise, lasting less than 1/75th of a second, that may be clearly audible depending on the context. A handy Windows utility called "CD Wave" (section (6-2-16)) is good at splitting large WAV files into smaller ones, and can do so on block boundaries.
If you want to mix WAV tracks together, take a look at Multiquence, http://www.goldwave.com/multiquence/index.html. A simpler merge utility is "wavmerge", from http://www.mrichter.com/cdr/files/files.htm.
Most CD players can only handle uncompressed audio in "Red Book" format. Some newer player, such as the AIWA CDC-MP3 and Philips Expanium, can play MP3 files from a CD-ROM. Such discs should be written in ISO-9660 with 8+3 filenames, and ought to use 128Kbps and "plain" stereo for broadest compatibility. The documentation for the I-Jam (http://www.ijamworld.com/) recommends putting no more than 50 MP3 files in a directory.
If you don't have such a player, though, you need to write a standard "Red Book" audio CD. The first step is to convert from whatever format the sound is in to WAV or AIFF. In some cases (e.g. MP3), many of the popular CD recording programs will do the conversion for you. If not, you will need to convert it to 44.1KHz 16-bit stereo PCM format. Once it's in WAV or (on the Mac) AIFF format, you can record it as you would audio taken from other CDs. Be sure to play it back once after you convert it to make sure that it came out okay.
For a tutorial on converting CD-DA to MP3 and vice-versa, see http://www.cdpage.com/Compact_Disc_Consulting/Tutorial/mp3.html. The "getting started" guide at http://help.mp3.com/help/ is worth reading, and the newsgroup FAQ for alt.binaries.sounds.mp3.* at http://www.mp3-faq.org/ is also useful. Making MP3s from CDs is discussed on http://mmsound.about.com/compute/mmsound/library/weekly/aa032700a.htm.
WMA is Windows Media Audio, part of Microsoft's attempt to create an architecture for "Digital Rights Management" protected media. A WMA player isn't supposed to let you hear any music you don't have the right to play. If you want to record it to CD, and the player won't let you do the conversion to WAV, you can still use a general-purpose sound recorder like Total Recorder to do the job.
There may or may not be a converter for the format you're interested in. Here are some links to try:
See http://www.howstuffworks.com/mp3.htm for an intro to MP3 technology. The site at http://privatewww.essex.ac.uk/~djmrob/mp3decoders/ has comparisons of various MP3 players.
http://www.sonicspot.com/multimediaconverters.html has a collection of converters for different formats.
If you *really* want to be able to play MP3-compressed songs while driving down the freeway, check out http://utter.chaos.org.uk/~altman/mp3mobile/ (or the commercial counterpart at http://www.empeg.com/).
CD-Text is a standard that allows disc and track information to be embedded on an audio CD. The data can be read by some CD players, providing a way to have disc information available without having to enter it manually or look it up in a database.
Adding CD-Text to the discs you record requires a compatible recorder and capable software. Support was scarce in mid-1999, but is more common now.
The currently available software supports writing of album title, artist names, and track titles, and can copy discs with CD-Text data already on them. Storing lyrics within the tracks is possible but not widely supported.
Not all CD players and CD-ROM drives can read CD-Text. If this feature is important to you, check the specifications before you buy. Some programs, notably Windows Media Player, claim to read CD-Text but will actually use an Internet database instead.
Some MD recorders have a feature that lets you copy the CD-Text info from audio CDs (e.g. "Joint Text"), but it appears that some CDs prohibit the copying. The result is the message "Text Protected".
The site http://www.ncf.carleton.ca/~aa571/cdtext.htm has some additional details.
You need to include the content and a browser on the CD. Some products that might be helpful are:
See http://www.microsoftfrontpage.com/content/ARTICLES/fp_to_cdrom.html for an article about creating HTML CDs using FrontPage 2002.
If it doesn't need to be in HTML format, the full Adobe Acrobat writer can reportedly convert an entire web site into a PDF document.
Incidentally, if you burn the disc with plain ISO-9660, you don't have to worry about the upper-case filenames conflicting with lower-case names in URLs. The filesystem code on Windows, Mac, and UNIX converts the names to upper case before comparing them. This may not hold for other formats, e.g. Rock Ridge.
In general, you shouldn't. Generally speaking, the only reason you'd need to clean a recorder or (for that matter) a CD-ROM drive is if you went and stuck your finger on the lens. Cleaning kits and well-intentioned Q-tips are unnecessary and potentially dangerous. If you push too hard on the lens while cleaning and damage the mounting, it will no longer matter how clean it is.
Some people report drives coming back to life after a careful cleaning, so there may be some value in doing so. If your drive has become increasingly flaky over time, cleaning it may help.
[ Personal note: I've never had to clean a lens in *any* CD player, including a flip-up top-loading boom box that I've had since mid-1990. I can *see* the dust inside, and I can see the lens, but it has no problem playing discs. I can't imagine how a recorder that's only a year or two old is going to collect enough dust to fail, unless you play a lot of really crusty discs. ]
If you have an overwhelming desire to clear loose dust out of your recorder, and can't or don't want to send it to a service center, use gentle(!) bursts of compressed air (like that used to clean camera lenses). The idea is to knock any dust loose without knocking the lens free of its mounting. A more vigorous approach is to use a Q-tip and isopropyl alcohol, but this should only be used if the previous approach fails.
The Repair FAQ at http://www.repairfaq.org/ has a section about CD-ROM drives that seems relevant. Find the "Compact Disc Players and CDROM Drives" section, and skip down to part 4. One relevant quote, from section 4.3, regarding "cleaning discs":
"I generally don't consider CD lens cleaning discs to be of much value for preventive maintenance since they may just move the crud around. However, for pure non-greasy dust (no tobacco smoke and no cooking grease), they probably do not hurt and may do a good enough job to put off a proper cleaning for a while longer. However, since there are absolutely no sorts of standards for these things, it is possible for a really poorly designed cleaning disc to damage the lens. In addition, if it doesn't look like a CD to the optical pickup or disc-in sensor, the lens cleaning disc may not even spin. So, the drawer closes, the drawer opens, and NOTHING has been accomplished!"
It depends on your recorder, media, and who you talk to. For example, some informal testing with the venerable Yamaha CDR-100 determined that it worked best at 4x speed with media certified for 4x writes. 1x worked almost as well, but 2x would occasionally produce discs with unrecoverable errors.
With audio CDs, the results are more subjective. Some people have asserted that you should always write at 1x, others have stated that 2x may actually be better. It depends on the recorder, media, player, and your ears. Try it both ways and listen. See section (4-18) for some notes on how you can write the same set of bits to two CDs and still have audible differences.
CD-R media is written by heating up tiny sections of the disc. When the disc spins faster, the laser has less time to shine on a particular spot, so the laser has to be controlled differently. Different formulations of media may require a different "write strategy" at certain speeds, and each recorder may adjust its write strategy differently to accommodate those speeds. This can potentially result in combinations of recorder and media that work perfectly at one speed but fail miserably at another.
Put simply, there's more to writing at high speed than just spinning faster. It's entirely possible that writing slowly to "high-speed" media will produce significantly worse results than writing to it quickly.
There is no One True Answer to this question. Do what works best for what you have. Some experimentation may be required.
See "The Speed of Sound: How Safe is High-Speed CD-Audio Recording?" at http://www.emedialive.com/EM2000/starrett5.html, for a very thorough analysis of audio disc quality at several different speeds. With some recorders and some media, it's actually better to write faster -- but in none of the tests performed did the error rate get anywhere near danger levels, regardless of speed.
See the graphs at http://www.digido.com/meadows.html for an examination of BLER (BLock Error Rate) with different recorders, different media, and different recording speeds. A few of the graphs show the same recorder and same media at different speeds, and in some cases the BLER increased at higher speeds, while in others it decreased.
There is some cause to believe that recording at higher speeds can result in increasing "jitter". This doesn't cause any difference in BLER or in the extracted audio, but is audible during playback. See section (2-41).
See http://www.cd-info.com/CDIC/History/Commentary/Parker/stcroix.html for commentary about "write strategy" selection and different media types.
In general, you don't need them. Software that burns CD-Rs has the necessary drivers built in.
If you want to use certain older recorders as CD-ROM drives, you may need drivers for them. See section (5-8).
This varies significantly from country to country. Information for USA and Canada follows. Most nations have some form of copyright protection that restricts duplication.
You are allowed to make an archival backup of software, but the same doesn't necessarily hold true for music. The Home Rights Recording Act will allow you to duplicate music under certain circumstances.
A discussion of the topic, including details on past and pending legislation, can be found on the Home Recording Rights Coalition web site at http://www.hrrc.org/. The text of the Home Rights Recording Act can also be found here.
The Recording Industry Association of America, which represents the music industry, has a web site at http://www.riaa.com/.
An article entitled, "Copying Music to CD: The Right, the Wrong, and the Law" is at http://www.emediapro.net/EM1998/starrett2.html.
http://www.brouhaha.com/~eric/bad_laws/dat_tax.html has some relevant information and pointers.
http://www.bmi.com/ and http://www.ascap.com/ have yet more perspectives on legislation.
Rules for copying software resemble those in the USA.
The rules for music are more lenient. Because of the media tax imposed by the Canadian government (see section (7-13)), you are allowed to copy any music for your own personal use. This means that you can go over to a friend's house and copy any number of discs you like, so long as they are for your own use. You are not allowed to make copies of music and then give them to others.
See http://www.cb-cda.gc.ca/decisions/toccopy-e.html, "Tariff of levies to be collected by CPCC in 1999 and 2000 for the sale of blank audio recording media in Canada".
The only possible basis in fact for the, "if it was recorded at 2x, you can't read it faster than 2x" rumors is that some drives have trouble reading CD-R media. Discs that are hard to read when spinning at 12x may become easier to read when spinning at 4x. It has also been noted that some recorders will write more legible discs at certain speeds (e.g. the Yamaha CDR-100, which works better at 1x or 4x than it does at 2x). None of this should lead anyone to conclude, however, that the write speed and read speed are tied directly together. The reader, writer, and media all have a role in determining how quickly a CD-R can spin and be readable.
It's also the case that discs written at high speed (say 8x) can be read by drives *slower* than 8x. So if you're distributing discs to people with old 4x CD-ROM drives, you don't have to worry about them not being able to read at 8x. Of course, if the CD-ROM is poorly constructed, or the writer is producing marginal discs at high speeds, you might see evidence to the contrary, but there is no technical barrier to reading discs recorded at 8x or 12x on a slower drive.
This is a tricky one because of issues with long filenames and file attributes. Mac CD-ROMs are typically burned with an HFS filesystem, not ISO-9660, and WinNT uses a different scheme for long filenames (Joliet) than UNIX does (Rock Ridge). Some variants of UNIX will recognize the Joliet names, but neither Windows nor the Mac understands Rock Ridge. You might be able to use an HFS CD-ROM on a platform other than the Mac, but if you're distributing software, it's not wise to assume that your customers will be able to do the same.
The easiest way to create a disc that will work on all platforms is to use plain level 1 ISO-9660, with 8+3 filenames and no special file attributes. If you need to include Mac applications as well as data -- or pretty much anything with a resource fork -- this simple approach won't work. Also, some older versions of Mac OS and HP/UX might not work as expected unless you record the disk without the usually-invisible version number (";1").
There is an Apple-defined extension to ISO-9660 that allows the Mac file and creator types to be present on an ISO-9660 filesystem. This allows most of the features of the Mac filesystem on an otherwise plain ISO-9660 disc. It's not clear how many of the software products in section (6-1) take advantage of this, but "mkhybrid" (section (6-1-32)) and MacImage ( section (6-2-10)) seem to. Section (3-5-3) has a URL to an Apple tech note with implementation details.
A common way to construct a disc for the Mac and PC is as a "hybrid" disc that has both an ISO-9660 filesystem and an HFS filesystem. To save space, the data itself is shared by both sections of the disc. This is possible because the ISO-9660 directory entries use an absolute block offset on the disc, so they can point at data residing in the HFS filesystem.
There are various applications that will do HFS/ISO-9660 hybrids. Roxio's Toast for the Mac and "mkhybrid" for the PC are two examples. Search for "hybrid" in the list of software in section (6-1) for more examples.
The issue of Joliet vs. Rock Ridge can also be solved, by including both kinds of extensions on the same disc. The "mkhybrid" program can include Joliet, Rock Ridge, and HFS all on the same disc. You can even have files appear on one kind but not the other, and rename files on the fly, allowing you to have a "readme.txt" with different contents for Mac, UNIX, and Windows.
With a little searching you can find an audio CD that will cause your CD player to show a negative track time when one track finishes and the next begins. The negative sections are usually filled with silence, but some rare discs will have material in them. If you seek directly to the track, you don't see (or hear) the negative-time section.
The trick here is also described in section (3-14). You can specify the start position of an audio track anywhere within the track. The start position is at time index 00:00 (in minutes and seconds, MM:SS), so the music before the start point is usually displayed with negative time values. When you seek directly to a track, the player jumps to time index 00:00, but when you play through from a previous track you hear the entire track.
When using CDRWIN-style cue sheets, the actual start of the track is at "index 00", and the place where the player seeks to is "index 01". The The distance between the indices is called the pre-gap. The Red Book standard requires that index 01 in track 01 be at least two seconds (150 sectors) from the start of the CD.
You can specify additional index markers, but most CD players will simply ignore them. Some CD-ROM games have tried to use the index markers as a form of copy protection, because they won't get copied automatically by many programs.
If you want to create your own discs with "hidden tracks", you need a program that gives you full control over where the index markers go (CDRWIN is one such program). Combine two (or more) tracks with an audio editor into a single file. Specify the file as a single track in the cue sheet, set "index 00" to time zero, and set "index 01" to a point right after the "hidden" song finishes. There are other ways to approach this, but this is probably the most straightforward.
It should be mentioned that the only truly "hidden" track is in track 1. Most CD players will play the entire disc, from index 01 on track 1, straight through to the end, so any tracks you try to "hide" in the middle of the disc are simply difficult to seek to. The only way to play audio tucked into the pre-gap in track 1 on most players is to hold down the rewind button.
For more information about unusual audio CDs, see "CD Oddities" at http://www.turbine.com/wj/oddcd/.
Absolutely. Infected CD-ROMs are every bit as nasty as infected floppies, if not worse: you can't disinfect the source media. It is prudent to scan your files before creating a CD-ROM for distribution, and it's not a bad idea to scan the CD-ROM afterward (in case somebody has cleverly infected your CD writing software).
The dangers of boot sector viruses on bootable CD-ROMs are probably low. Because the boot sector is created directly by the recording software, and can't be modified after it has been written, the opportunity for infection is small.
You don't. With a CD-ROM you could use multisession writes to hide unwanted data, but you can't create multisession audio CDs. (Well, you can create them, but nothing outside of a CD-ROM drive will be able to play the tracks outside the first session.)
On CD-RW media, it might be possible to overwrite an individual track. You would need software that supported this capability. Erasing the disc and starting over is probably easier.
Requests for information on how to copy recent games occasionally sprout up on the newsgroups. Generally the publisher has employed some form of copy protection that prevents the disc from being duplicated easily. If you try to play the game from the duplicate, the game will usually act as if the CD-ROM weren't present and tell you to insert it.
Most publishers are well aware that there is no such thing as an unbreakable copy protection scheme. It is possible though to implement a method effective enough to slow the tide. If you don't believe that, start counting posts the next time a popular game with decent protection is released. See section (2-4) for some technical details, and section (3-42) for a discussion of why you can't write a general-purpose disc copier that works for everything.
If you're looking for information, the most appropriate places to search are "warez" newsgroups and web sites. Searching the net for tips is a good way to get started. Be forewarned that any "cracks" you download may very well also be viruses, and that if you give away or accept a copy of the disc from someone else you are probably breaking the law.
Aiding and abeting the illegal distribution of copyrighted works is not part of this document's charter. There are plenty of newsgroups and web sites devoted to the subject, so please don't waste bandwidth in "legitimate" forums asking for cracks. A search engine such as http://www.google.com/ will turn up many sites with such information.
Incidentally, the government of the USA and several other countries are starting to crack down on illegal trading of software and digital video. See http://www.usdoj.gov/opa/pr/2001/December/01_crm_643.htm for a press release on a December 11 2001 crackdown.
First and foremost: you do not need to format a disc unless you're using a packet writing program like DirectCD. If you're running a program to create a CD, chances are good that you don't need to format it. If you're using "drive letter access", i.e. treating the CD-R or CD-RW like a big floppy disk, then you do need to format it.
Simple rule of thumb: don't format it. Most software that needs a formatted disc will format it for you as needed.
Formatting and erasing are different things. Formatting prepares a disc for recording. On a CD-R it writes a few basic things, on CD-RW it may write to most of the disc. The fixed-packet formatting that DirectCD does for CD-RW discs takes about 50 minutes on a 2x-speed rewritable drive.
Erasing, which can only be done to CD-RW media, restores the disc to a pristine state. If you want to erase a disc, use the software that came with your CD-ReWritable drive. Somewhere in the army of applications and mountain of menus is the command you're looking for.
The difference between "erase" and "quick erase" is that the former erases the entire disc, while the latter just stomps on the Table of Contents (TOC). It's like erasing the directory off of a floppy disk. The file data is still there, but since there's nothing pointing to it, the disc appears empty. (Some people have asked if it's possible to recover data from a quick-erased disc. Acodisc can do this; see section (4-35).)
The difference between "format" and "fast format" (such as is offered on the HP8100/Sony CRX100) is of a different nature. Both format the entire disc, and both operate at the same speed, but the "fast" format allows you to use the drive before formatting has completed. After a few minutes, you are allowed to access the drive while the formatting process continues in the background.
Incidentally, most conventional (pre-mastering) software will refuse to record on a disc that has been formatted for packet writing. In some cases the error message may be a confusing remark that insists the disc isn't writable.
A common problem when creating an audio CD compiled from many different sources is that the sound is at different volume levels. This can be slight or, after you've cranked up the volume to hear the first track, very much the opposite of slight.
There are actually two issues that determine how loud the music sounds. The first is the signal amplitude. Put simply, if you open a WAV file, this is how close to maximum the squiggly line gets. You can adjust the WAV file so that the highest amplitude is at maximum with the "normalize peak" function of a sound editor. Some programs, such as Roxio's Spin Doctor, may even do this for you automatically.
The second major issue is the dynamic range compression. This differs from data rate compression in that it doesn't make the WAV file smaller. Instead, it can make the quiet parts louder and the loud parts quieter.
A CD-DA has a dynamic range of about 96dB. If a symphony is recorded with a range of more than 110dB, it has to be compressed to fit on a CD-DA. In practice, you don't want whispers to be inaudible and shouts to be deafening, so the audio is often squeezed into an even narrower range. Radio stations often compress their broadcasts "up" so that music can be heard more clearly by listeners in cars or work environments.
(According to Ken Pohlmann's _Principles of Digital Audio_, 4th edition, page 35, ideal 16-bit quantization of a sinusoidal waveform is 6.02n+1.76 decibels, or 98.08dB. Using "dithering" techniques, it's possible to extend the effective resolution well beyond this, because of the way the ear perceives sound. There is an *excellent* introductory article at http://www.digido.com/ditheressay.html. Compression is more often employed on pop music recordings, where louder is better, than something like classical music, where accurate reproduction is desirable.)
To make a CD that sounds like it has equal volume across all tracks, you need to have the average sound level uniform across all tracks and have the peak volume be about the same on all tracks. One program that does essentially this is Audiograbber v1.40 and later, available as shareware from http://www.audiograbber.com-us.net/. (As of v1.41, you went into "Normalize Settings" and hit the "Advanced" button.) The tool is a little clumsy for serious audio mastering, but should do fine for preparing a "mix" CD that you'll be listening to in your car.
Another tool is "WAV file leveller", at http://www.plompy.co.uk/software.
Some programs approximate compression by letting you normalize against average RMS power. In this case, you are using a value that more closely matches the apparent loudness of the recording.
If you aren't dissuaded yet, http://www.digido.com/compression.html has an excellent article on compression, intended primarily for the budding recording artist but a good general reference nonetheless. Cool Edit 2000, available as shareware (section (6-2-14)), can do different kinds of compression, and is fun to play with.
Sidebar: "dB" is the abbreviation for "decibel", a signal strength ratio measured on a logarithmic scale. In a WAV editor like Cool Edit, which can show the sound level in dB, the signal level doubles every time you add 6dB, and the "loudness" doubles every 10dB. This is different from signal power levels, which double every 3dB (what you see in a WAV editor is analogous to voltage, not power). Detailed information is available from the Acoustics FAQ at http://www.campanellaacoustics.com/faq.htm. See also http://www.ews64.com/mcdecibels.html and http://www.modrec.com/about/excerpt.php. There is a comparison table at http://www.gcaudio.com/Archives/volatgeloudness.htm that breaks things down nicely.
A commonly posed question from the newsgroups: "what software can do bit-for-bit copies?" The expectation is software that can make an exact copy of the original.
There isn't any. If it helps to have a (convenient albeit somewhat inaccurate) mental image, picture a long string of bits arranged in a spiral. There are bits at the start of the spiral that you can't copy (the lead-in area), there are bits outside the spiral that you can usually copy if you request them ("raw" MODE-1 CD-ROM ECC and sector goop), and there are bits *under* the spiral that are blurry and hard to see (the subcode data).
What's more, there are copy protection features, such as *physically* damaged blocks, that a recorder isn't generally capable of writing. Other tricks, such as out-of-specification track lengths, can't be duplicated by most CD recorders because the firmware refuses to write them.
In no event can you guarantee an exact duplicate of the level 1 ECC (CIRC) encoding. In practice this doesn't matter, since no CD-ROM drive provides an interface for reading it directly.
Making a "bit-for-bit" copy of a disc would require reading the data at the lowest possible level, something that no production CD-ROM drive is capable of doing. Even if it were possible, there aren't any CD recorders that can write that sort of data.
Because of these limitations, you have to read a sector of data as a sector of data, not as a collection of frames scattered over half the circumference of the disc. The best you can do currently is "raw DAO-96" (section (3-51)), which reads the subcode data along with the the sector data.
Bear in mind that CD-ROM drives and CD recorders were designed for people who want to read and write data, not decipher arcane standards documents and perform their own error correction. Creating exact one-off copies was not a major consideration of the original design.
In general, however, you don't *need* a "bit-perfect" duplicate of the original. If what you're copying is a simple MODE-1 CD-ROM, you can make an "identical" copy by reading the sectors off the original and writing them to a duplicate. For most situations this is good enough: you have copied the bits that matter.
On the other hand, if it's a copy-protected CD-ROM with index markers in strange places, you have to use software and hardware that can see the "blurry bits" reliably and copy them.
See also sections (2-43), (3-1-1), (3-18), (3-39), and (6-1-49).
The name of a CD-ROM is determined by the CD-ROM volume label. This determines how the disc shows up on the Mac or Windows.
The ISO-9660 standard limits the characters in the volume name to the same set of characters allowed in a filename, namely A-Z, 0-9, '.', and '_'. Some programs enforce strict adherence to the standard, while others are more relaxed.
For example, if you wanted to create a disc with Nero that had a hyphen in the volume name, you would go into the "file options" and change the Character Set to "ASCII". Nero will then allow a broader range of characters. Other programs may or may not have similar features.
Remember that standards are guidelines, not laws enforced by threat of punishment. You are welcome to create discs that deviate from the standard in any way you choose. The only price you will pay is that, if you stray too far from the standard, your disc may not be readable by everyone. For the specific case of a volume label, deviations are pretty harmless.
Applications like "Toast" insist on showing the data track only. You can play the audio tracks, but you can't seem to extract them.
SoundJam MP from http://www.soundjam.com/ is reported to do the trick. The CD-ROM toolkit from FWB (http://www.fwb.com/) might also be of use.
There are two basic approaches: (1) run the uninstall program, or (2) make changes to several entries in the Windows registry.
You CANNOT disable it by killing a task.All these really do is stop the DirectCD control interface from running. The icon is gone from the system tray, but DirectCD itself is still active, which you can verify by inserting an unfinalized packet-written disc. If DirectCD were actually disabled, the disc would be unreadable.
You CANNOT disable it by un-checking it in msconfig.
You CANNOT disable it by removing it from the system StartUp list.
Writing data to such a disc without the user interface component active can lead to data corruption, because some of the safeguards are no longer in place. It's like you've taken the steering wheel off the car while it's still rolling.
If you do choose to use one of the "easy" methods, you will probably be okay so long as you don't try to write to a disc with packet writing.
DirectCD puts some drivers in C:\Windows\System\Iosubsys\. The set appears to be CDUDFRW.VXD, CDUDF.VXD, CDRPWD.VXD, and CDR4VSD.VXD. If you are having trouble un-installing DirectCD, check for the presence of these files, and rename the extension to ".VX_" if found.
NOTE: the DirectCD icon in the system tray is different from and independent of the "Create CD" icon that Easy CD Creator 4 adds to the system tray. You can get rid of that by right-clicking on it and telling it not to load.
You don't. The ISO-9660 specification requires that the files appear sorted.
Most modern OSs sort directories anyway, so unless you're greatly concerned about the appearance under DOS, there's little value here anyway.
Encrypt the data on it. See section (3-19) for options.
That depends on what you're trying to accomplish. There are two issues that complicate matters:
Some people have CD players that will play songs from every session. If you do, and compatibility with other players isn't important, you can write each group of tracks into its own session. The down side of this approach is that there is an appreciable amount of overhead when opening a new session (23MB for the first and 14MB for each additional one).
If your hard drive has enough space, you can just keep the WAV files on the drive, and burn the disc all at once. If it doesn't, you can write the tracks to a CD-R or CD-RW disc as WAV files on CD-ROM, and record from there. Write a new CD-R or CD-RW every time you get more tracks. (The advantage to using CD-ROM is that additional error correction is used.)
It isn't possible to take the contents of a DVD-Video or DVD-ROM and record the whole thing onto a CD-R, unless the DVD is nearly empty. The capacity of DVD discs is considerably greater. Generally speaking, you can't play DVD content from a CD-R disc anyway, because the DVD drive needs to read encryption keys from outside the filesystem area.
You could, of course, capture the video from a DVD-Video disc with a video capture board, re-encode it with MPEG-1, and write that as a VideoCD. The quality would be VHS-grade though. (You can get better results with MP3 audio and MPEG-4 video, but the process is a little convoluted. See http://www.digital-digest.com/dvd/support/dvd2mpeg4.html.) The next section talks about some ads you might have seen for products that do this.
You may have heard of DivX (sometimes "DivX ;-)"). Originally the name for a limited-playback DVD system, it now usually refers to MPEG-4 encoding of DVD video. See http://www.divx-digest.com/help.html for more details.
If you're only interested in the audio portion of a DVD-Video, you can extract the AC3 audio directly from the .VOB file, using some freely available utilities (notably "ac3dec" and the elusive "DeCSS"). You will need to convert the audio from 48KHz to 44.1KHz. You can also capture it under Windows with Total Recorder (6-2-19).
The story is the same with DVD-ROM: you can probably copy it to a CD-R if it will fit. If the contents only took up about 650MB, though, it probably wouldn't have been shipped on a DVD-ROM.
I'm guessing you've also heard of ways to get rich by sending money to other people, legal ways to get your bad credit history erased, and drug-free side-effect-free low-cost super cures made from all natural ingredients on distant tropical islands.
They're all nonsense. I can't help you if you believe in the above, but I can speak to copying DVDs with a CD recorder. Here's a piece from a message that was spammed at me (spelling and grammar errors left uncorrected):
COPY ANY DVD MOVIE
With our revolutionary software you can copy virtually any DVD Movie
using your existing equiptment! Conventional DVD copying
equiptment can cost thousands of $$$
Our revolutionary software cost less than the price of 2 DVD Movies!If you go to the web site, it goes on to say:
Learn How To Burn DVD's onto Regular CD-R Discs and watch your newAnother, possibly unrelated, site says:
movies on Any DVD Player, not just the computer DVD.
No DVD Drive Required!!!
With detailed, easy to follow, step-by-step instructions, you canIt has a link for their "frequently asked questions" document, but you have to give them your e-mail address to get it. Any company that refuses to give you information until you submit to their spam list is best avoided.
BURN your own DVD Video using nothing more than our software and
o No DVD Burner Required
o Superior Reproduction Quality
Let's start with the facts:
This software will let you create a movie that could be played back in computers or *some* DVD players -- not all DVD players support CD-R media, and not all will play VideoCD -- but at roughly VHS quality, and without any of the features that make DVDs special. Most notably, you will lose all of the menus, audio options, and special features. You will not be burning "DVD Video", and in some parts of the world (most notably the USA) you will be breaking the law even if the copy is for personal use.
Software that does this sort of thing can be found, for free, on various sites on the Internet. (Because of the legal issues, it isn't always available in one place for long.) If you really want low-quality MPEG editions, save your money and search the web for DVD copiers or converters, and download the software for free instead of giving money to spammers. (The previous section has a couple of links that might be useful.)
A program that copies the entire disc as an image should work. Don't try to copy it as a collection of files.
You can create a hybrid HFS (Mac), Rock Ridge (UNIX), and Joliet (Windows) CD-ROM with "mkhybrid" in section (6-1-32). The output of the program is a simple ISO-9660 image file. It stands to reason that you should be able to copy such discs as easily as you can create them.
The same applies to copying arbitrary discs from the Mac, or any other platform -- just copy it as a disc, and you should be fine.
If you're trying to copy a game, and it doesn't work, see (3-39).
A sector on an audio CD holds 2352 bytes, enough for 1/75 of a second of stereo sound. A sector on a MODE-1 CD-ROM holds 2048 bytes of data. The 304 "lost" bytes are used for sector addressing, synchronization, and error correction.
If you read a MODE-1 CD-ROM sector in "cooked" mode, you get 2048 bytes of data. When you write that to a CD-R or CD-RW, the error correction bytes are reconstructed. If you read that sector in "raw" mode, you get all 2352 bytes of data. If you simply wrote those bytes to a CD-R, any errors that slipped past the CIRC encoding while reading would be propagated, and could result in generation loss (see sections (2-17) and (3-18)).
There are times when you don't *want* to have the error correction reconstructed. For example, some games deliberately distort the error correction bytes as a form of copy protection. See section (2-4).
The recording software has the option of error-correcting the 2048 bytes of CD-ROM data and even regenerating the ECC data. Doing either reduces the risk of generation loss; doing both eliminates the risk by effectively doing a "cooked" read and write. (Apparently some drives will error-correct CD-ROM data for you even in "raw" mode.)
To copy a disc in "raw" mode, you need the right reader, the right writer, and the right software. Programs like CloneCD specialize in "raw" copies, but require that the CD-ROM drive used to read discs and the recorder used to write them support "raw" reads and writes. The web page for CloneCD (6-1-49) is a good place to look for a list of capable hardware.
"RAW DAO-96" refers to a method for writing "raw" 2352 byte sectors with 96 bytes of associated P-W subcode channel data (section (2-6)). This is useful for copying discs with CD+G, CD-Text, and certain forms of copy protection. "DAO" refers to its use in combination with disc-at-once recording.
There's also "RAW DAO-94", which is the same as DAO-96 except that the two bytes of Q channel CRC data are always generated by the recorder, and "RAW DAO-16", which includes only the P-Q subcode channels.
A "cross-fade" is a smooth transition from one track into another. If done properly, with compatible music, the tracks appear to blend into one another.
Some of the fancier recording applications, such as Sound Forge (http://www.sonicfoundry.com/) and Waveburner (6-1-55), will do cross-fades. An "Advanced CrossFading" plug-in for Winamp can do them; set the output device to a file on disc (with a "disk writer plug-in"?), and play the music you want to record.
It's important to use disc-at-once recording when writing the tracks to avoid having two-second gaps inserted. See section (3-26).
If you want to create a CD that includes songs from several other CDs, there are two basic approaches:
If you have a stand-alone audio CD recorder, this should be straightforward. Either you have a microphone input or you don't.
On a computer, you probably don't want to do this. The greatest advantage of using a computer-attached recorder is that you can edit the result before recording it. CD-R is write-once media, so if you make a mistake, you can't fix it later.
If you're determined to do this, Roxio's Spin Doctor (part of Easy CD Creator) can do what you want. Connect the microphone to the input on the PC sound card, start up the software, and record when ready.
The situation on non-PC platforms is similar: you can do it if your software supports it.
Yes, though the quality won't be as good as if you had recorded directly from the original CD.
MP3 is a "lossy" compression format, meaning that it gets its exceptional compression ratios by throwing some of the data away. (MP3 can get a 10:1 reduction with hardly any degradation in audible quality; "lossless" compression is hard-pressed to do better than 2:1 on 16-bit samples.) The clever part about MP3 is the way it figures out what parts of the audio to throw away and what to keep, based on a model of human hearing.
Because it's a lossy format, every time you compress something you lose some of the quality forever. The smaller you compress it, the more you lose. The loss is more easily audible on some music than others, and if your equipment (or your ears) aren't very good you may not notice it at all.
If you like to copy CDs by ripping them into MP3 format and then recording them to MP3, be aware that your copies aren't quite as good as your originals. At 160Kbps it's going to be hard to notice, but at 64Kbps it should be easy to tell the difference between the original and the copy.
(Side note: if you want to do a double-blind test, play the original and the duplicate in random order for somebody else, and ask them if they can identify the original music. The test isn't to tell that the discs sound *different*, but rather to figure out which disc sounds *better*.)
For more information about lossy and lossless audio compression, see:
You have a few options.
You can do a trivial check of an ISO disc image with WinImage. See section (6-2-2).
Under Linux, you can mount it via the "loopback" filesystem, e.g.: "mount ./cdimg.iso /mnt/test -t iso9660 -o loop".
Under DOS/Windows, you can "SUBST" a directory to make it look like a drive, e.g. "SUBST J: \goodies\NewCD" will make the contents of "\goodies\NewCD" appear to be mounted on the J: drive. This is a useful way to test autorun.inf files.
A more robust approach under Windows is to use a CD emulator. These programs usually use their own proprietary disc formats, but some converters are available (e.g. http://www.bluebitter.de/), and some can mount ISO images directly. Examples include Microtest Virtual CD (http://www.virtualcd-online.com/), Paragon CD Emulator (http://www.cdrom-emulator.com/), and Daemon Tools (http://www.daemon-tools.com/).
If you write files to a CD-R with conventional recording and then try to copy them back, under Windows the files will all have their "read only" flags set. This can be annoying for documents you want to update.
The files aren't written to the disc as "read only". There isn't any such permission flag in the filesystem. They're simply presented that way by Microsoft operating systems. Mac OS deals with this in a nicer way, showing unlocked files on write-protected media, rather than the dopey Microsoft approach of showing write-protected files on unlocked media.
You can avoid this situation entirely by using packet writing (where you just copy files to the disc like a big floppy, e.g. with DirectCD), which preserves the file attributes, or by using backup software, which will restore the files to their original state. Stuffing the files into a ZIP archive works too, but may be less convenient than other approaches.
If you've already got the read-only files, changing them back to read-write isn't too hard. Some approaches:
If you're using Win2K or WinXP, right-click on the top-most folder(s), and un-check the read-only box. You will be asked if you want to apply the change to all files and folders in the folder. Say "yes".
For DOS or older versions of Windows, from a DOS prompt run "ATTRIB -R *.* /S" on every subdirectory with read-only files in it.
If you prefer a Windows application, try "ReadOnly" from http://www.sente.co.uk/downloads.htm. They also have a more sophisticated application called "FlagRASH".
If you can boot into Linux, su to root, mount the volume as vfat, cd to the directory in question, and do "find . -print | xargs chmod +w" to enable write permission for all files in the current directory and in all subdirectories. If you've got the GNU utilities, use "find . -print0 | xargs -0 chmod +w" instead, because it'll work correctly on files with spaces in the names. (Of course, if you're a Linux user, you could just use mkisofs with the appropriate options and have Rock Ridge file permissions that match the originals, but this is a Windows question.)
There is no general way to access a CD recorder on a remote machine. You need to have software running on the machine with the recorder. This might be something as simple as DirectCD, to provide a filesystem that Windows can write files directly to, or something fancy that accepts disc images and queues them for recording.
Ahead's NeroNET (http://www.nero.com/) provides a client/server model for sharing CD recorders. See also CD Studio+ (section (6-1-6)).
This is usually referred to as "spanning", and is a standard feature of most backup software (see section (6-7)). With a little extra effort, you can accomplish the same thing with standard software.
One approach under Windows is to create a ZIP archive with WinZip (http://www.winzip.com/), and then use the "Split" item on the Actions menu to break the archive into pieces small enough to fit onto CD-Rs. The feature was originally created to split archives across multiple floppy discs, but it works just as well with 650MB pieces.
On a UNIX system, use the "split" command, e.g. "split -b 650m myfile". Write each file to a separate disc, and combine them later with "cat". These commands have been a standard part of UNIX for just about forever, so you should have no trouble finding them.
The best approach is the one that leaves you with a 100% readable disc today and a few years down the road. The key ingredients are:
Problems that arise when burning a CD-R.
Some suggestions that fix most common problems:
It means you have an attractive new coaster for your table.
Generally speaking, the CD recording process can't be interrupted in mid-session. Once the laser starts writing, any interruption would create a physical gap on the disc that could confuse CD readers. The recorder must always have data to write, from the moment the recording starts until the session ends. To avoid a situation where a temporary slowdown in the computer causes the write process to fail, the makers of CD recorders put a write buffer in the drive, usually between 512K and 4MB in size. Data read from the hard drive, tape, or another CD is stored in the buffer, and pulled out as needed by the recorder.
If the recorder requests data from the write buffer, but there's none there, it's called a buffer underrun. The disc is still spinning, but there's no data to write, so the recording process aborts.
This was a very common and very annoying problem for many years, so most recorders released in 2001 or later have optional "buffer underrun protection" features available. See section (2-31).
You can sometimes use a disc that failed during writing by closing the session and starting another, assuming there's enough space left on the CD, and assuming your pre-mastering software didn't choose to finalize the disc for you. If you were using disc-at-once recording, you're probably out of luck.
Advice for preventing buffer underruns is scattered throughout this FAQ. A brief summary:
Some game discs use a form of copy protection where bad sectors are deliberately placed on the original CD. Attempting to copy one of these discs on the fly may fail, because some CD-ROM drives slow down and repeatedly try to read the "damaged" blocks. The slowdown may result in a buffer underrun before the CD-ROM drive reports an error.
A utility included with Microsoft Office, called "FindFast", will occasionally start up and scan your hard drives. Disabling this by deleting the shortcut in the Windows\Start Menu\Programs\StartUp folder may be necessary.
If you're using Windows, see the sub-sections on Auto-Insert Notification and VCACHE settings, below.
http://www.roxio.com/en/support/cdr/bufunder.html has a comprehensive collection of buffer underrun info.
http://www.adaptec.com/support/configuration/cdrec.html is interesting reading for users with CD-Rs attached to Adaptec SCSI cards. They're pretty far on the conservative side, but if you're having trouble this may help you.
An article by Dana Parker entitled "CD-R on the Safe Side: Seven Rules of Successful CD Recording" in the April 1997 issue of Emedia Professional (formerly at http://www.emediapro.net/EMtocs/emtocapr.html) listed the Seven Habits of Successful CD-R Users:
(Side note for search engines: some versions of Ahead's Nero refer to buffer underruns as "loss of streaming".)
Some of the Windows-based recording software recommend turning off Auto-Insert Notification. Having this on can interfere with closing sessions or even just inserting discs into the drive. Most of the recent software will disable it automatically, but some of the older products require you to disable it manually. You can do so under Win95/Win98 by opening the "System" icon in the Control Panel, and selecting "Device Manager". For each item under CD-ROM, select the device, click on the "Settings" tab, and make sure the "Auto Insert Notification" checkbox is unchecked. [With a vanilla Win95 setup I got SCSI errors when AIN was off for my CD-R but on for my CD-ROM, even if the CD-ROM drive wasn't in use at the time.]
If you're using WinNT, you can turn it off with the "TweakUI" program available in PowerToys (available from the Microsoft web site at http://www.microsoft.com/), or by modifying a registry key with Regedit32 (0=disabled, 1=enabled):
HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ Cdrom \ AutorunIf your software automatically turns AIN off, and you can't figure out how to turn it back on, the TweakUI program may be able to help. Check the "Paranoia" settings. (Incidentally, if installing the Power Toys screws up your icons, select "Rebuild Icons" from the "Repair" menu.) If you turn it off and on again, You may have to reboot in some configurations before it will work again.
Sidebar: the trouble with Auto Insert Notification is that it periodically attempts to find a valid disc in the CD recorder. A blank disc isn't very interesting to Windows, so nothing happens. When the table of contents is written to the disc, it suddenly becomes interesting; and if Autorun or Autoplay are enabled, enough activity is generated by Windows' attempts to read the disc that the write fails.
Because it only affects CDs with actual data being written to them, a test write won't end in failure. It can be very frustrating to have 100% success with test writes and 100% failures with actual writes! With disc-at-once recording, the process will abort very near the start of recording, probably leaving an empty but useless disc. With track-at-once recording, it will fail at the end, and you may still be able to finalize the disc. Audio CDs will most likely work fine even if interrupted at the end of the write process.
IMPORTANT: if you are using DirectCD for Windows, you must have AIN turned *on*, or some things won't work quite right. The most obvious failure mode is that long filenames aren't shown, but some reports indicate that data on the disc can get trashed as well. This can make life interesting if you're also using a conventional writing application, unless the application is good about turning AIN off before writing. The other Windows applications currently sold by Roxio (notably Easy CD Creator) will automatically disable Auto-Insert Notification when appropriate and re-enable it afterward, so you don't have to worry about AIN at all.
One problem with Win95 is that by default the size of the file cache is unrestricted. This means that all available memory will eventually get filled up with file data, which will cause the virtual memory system to start swapping out pages from executing applications. When something needs to be executed from a page that has been swapped out, it takes time to pull it back in off the disk. While this is happening, the CD recorder's buffer could drain completely.
The procedure is simple:
If you have an older system with only about 16MB of RAM, you might want to use instead:
MinFileCache = 512The [vcache] change has reportedly cured severe buffer underrun problems with some versions of CDRWIN and removed popping noises during digital audio extraction with Easy CD Creator. It's a good thing to do to any PC running Win95. It's not necessary for WinNT. It's not clear whether this will help with Win98, but it doesn't seem to hurt.
MaxFileCache = 4096
If you are uncomfortable tweaking your SYSTEM.INI file, try CacheMan at http://www.outertech.com/. It allows you to modify the above settings, and a few more besides.
Typical symptoms can be described like this:
The SCSI driver needs to believe that the CD-ROM drive can handle multisession discs. Most likely you will need to update your SCSI drivers before this will work.
(This problem was reported with an HP4020i and a Buslogic BT946C controller; if you have an HP drive you should get the c4324hlp.vxd driver from the HP web site. See section 6 for the address.)
One possible cause of this problem is writing a multisession disc in MODE-1 format. Some older CD-ROM drives incorrectly assume that a MODE-1 disc can't be multisession, so they don't look for additional sessions unless it's written in MODE-2 (CD-ROM/XA) format.
Also, if the final session on the CD isn't closed, standard CD players may become confused (the NEC 6Xi certainly does under Win95). This doesn't mean that the *disc* must be closed, just that the *session* must be closed. (Actually, the NEC 6Xi doesn't like open discs either... sigh.)
A note on one of the Ricoh pages indicates that the Ricoh 1420C is unable to read sessions smaller than 3 minutes (about 26MB) until firmware 1.6x.
There's a couple of possibilities. One is that your data source can't keep up with the CD-R; try using disc-at-once writing from a disc image with the speed set to 1x. If it seems to be getting worse over time, you may just need to defragment your hard drive.
If that fails, a number of people have discovered that the problem is a faulty CD-R unit (similar behavior has been reported on Sony and HP units, which have different mechanisms). You should try 1x writing from a fast source and with different sets of data before contacting the manufacturer, since they will likely tell you to do exactly that anyway.
Be sure that there aren't environmental factors creating difficulties. CD-R units are usually built to handle small shocks, but having a set of speakers playing loud music on the same table as a CD-R may cause it to skip, resulting in a failed write. Sonic booms, heavy construction equipment, and nuclear detonations may have similar effects.
It's also possible that you simply have a bad batch of media. Try a different type and brand of disc. Some distributors (e.g. dataDisc) will exchange media that's provably defective.
Be careful with Advanced Power Management functions on some PCs. If the keyboard and IDE devices are completely idle, the system may decide that nothing is going on and switch to a low-power mode. Ditto for screen savers that kick in after the system has been idle for a certain period.
Most CD recorders need to clear their memory between the "test" pass and the "write" pass. For some recorders, the only command that does this is "eject". If the recorder has a tray it just goes out and back in, but if it uses a caddy manual intervention is needed.
Some CD-R packages allow you to start the real write pass a few seconds after the test pass has succeeded. They may not disable this even though they know that the disc will have to be ejected. Make sure the option is set to "wait until told to continue."
A very simple test is to take a CD that DOES work, copy it, and try both (this ensures that your problems aren't being caused by, for example, a drive that doesn't support multisession CDs).
Sometimes the firmware can be at issue. In one specific case, a Goldstar GCD580B CD-ROM drive was able to read CD-Rs under Win95 but not MS-DOS 6.22. Upgrading the firmware from v1.01 to v1.24 solved the problem.
If it fails with different kinds of media, the CD-ROM drive either doesn't like discs written with your recorder, or doesn't like CD-R media at all. In one case, returning the CD-ROM for an identical unit resolved the problems.
While there are stringent specifications for discs, there are no such specifications for CD players and CD-ROM drives. They just have to play the discs. If the disc and the drive are both marginal, you lose.
The ISO-9660 standard says the version number (a semicolon followed by a number at the end of every filename) has to be there. Most operating systems simply ignore it, but until recently the Mac didn't, causing some problems.
(For the Mac, look at "ISO 9660 File Access" in the System:Extensions folder with Command-I. If the version shown is 5.0 or greater, your system should handle the version numbers just fine. If not, you should update your system software.)
If you can't find a way to work around it, "mkisofs" has an option to omit the version number when constructing an ISO-9660 image.
http://www.adaptec.com/support/configuration/cdrec.html has some advice on SCSI configuration. Basically, check your cabling and termination (see section (4-17) for more advice there), turn off features you don't need, and make sure Auto Insert Notification is off (see section (4-1-1)).
(This is for failures other than buffer underruns. For those, see section (4-1) and perhaps section (4-4).)
If it's failing right as the disc is being finalized, and you're recording in track-at-once mode, try recording in disc-at-once mode instead. It has been suggested that some recorder+media combinations have trouble reading the PMA (Program Memory Area, where a copy of the TOC is kept until the disc is finalized) at the end of a write. With disc-at-once mode the TOC is written early, so it doesn't have to get read out of the PMA. See section (2-19) for the low-down on disc finalization.
When in doubt, check your ASPI layer. See section (4-44).
One user with an ATAPI recorder found that disabling DMA (from the Win98 peripheral properties) made things better.
Try letting the drive cool down (leave the machine off for a couple of hours if you have an internal drive). Power up the machine and immediately record the disc. Sometimes heat buildup can cause problems, though this is less common with recent drives.
This was happening frequently with the HP4020i running off an AdvanSys SCSI card under Win311 (i.e. WfWG). The solution here was to remove IFSHLP.SYS from the CONFIG.SYS. (IFSHLP.SYS is somehow involved with 32-bit file access and network support, so you may have to disable both of these before disabling IFSHLP. You may have better luck under Win95.)
Another user with the same setup found that doing power-up diagnostics and device reset right before burning the CD helped.
This seems to happen on Philips CDD2000-based units, such as the HP4020i, usually a short while after the warranty runs out. The most common cause is a spring that weakens with age, but it might also be due to lubrication breakdown. After a while, the recorder starts failing when trying to write beyond a certain point on the disc.
The ways of dealing with this range from minor system changes to the placement of chicken entrails on selected components. Reducing the DMA rate on the AdvanSys SCSI card (for the HP4020i) may help, buying better SCSI cables and checking for proper termination may make a difference, or even powering off and on again right before the burn. For some users, however, the problem is mechanical rather than spiritual.
One user was told by Philips tech support that if error 50h (write append) occurs, it means the drive has to be returned to the repair center. Other users have been told that the error can occur when attempting to write an empty directory or zero-length file. Under Easy-CD Pro '95, this is reported as error 171-00-50-00 (see the Roxio web site for a complete list of error codes).
If the fault is caused by the worn spring, it may be possible to fix the problem by replacing the spring. This will definitely void your warranty, and you shouldn't even think about trying this unless the only alternative is to throw the drive away. Jonathan Oei posted some details about the process (search for comp.publish.cdrom.hardware, subject "CDD2000 & Spring Fix", on http://newsone.net/), and a detailed description of the procedure can be found on http://www.fadden.com/doc/fix-hp4020i.txt.
This procedure requires some special tools (mini torx drivers and really fine jeweller's pliers), and involves disassembling much of the drive. If you open up the drive and remove the circuit boards, you will see that the laser writing assembly is moved by a DC stepper motor. The motor has a plastic drive gear that is meshed with a plastic "rack" on the laser. The spring in question is a piece of wire that pushes the rack against the drive gear, so when it weakens the gear slips and the write fails. Replacing the 0.012" wire with a 0.02" diameter wire solves the problem.
The high temperature in the drive may contribute to the breakdown of the lubricants that allow the laser head to travel. You may be able to prevent the situation by installing a fan.
This question is also covered in the HP4020i FAQ, available at http://www.cd-info.com/CDIC/Technology/CD-R/HP-FAQ.html.
There's a 150-sector postgap at the end of the data track. Most programs deal with this automatically, some older ones don't. If you're getting errors, try subtracting 150 from the total number of sectors to read for that track.
There are a few of possibilities, some software and some hardware.
It may be that the system is looking at the disc, not finding a TOC (table of contents), and ejecting it as useless. One way to tell the difference between the operating system rejecting the CD and the drive rejecting the CD is to unplug the SCSI or IDE cable from the back of the CD recorder before inserting the disc.
If the drive pauses for a little while before ejecting, it may be rejecting the media. On some units you get a blinking warning light instead. If this is happening, try a different brand of media.
If the problem is the operating system, you probably need to disable certain features. Under Win95, disable auto insertion for all CD-ROM devices (see section (4-1)). One user found that reinstalling Win95 helped. On the Mac, you may just need more recent drivers. On a Solaris system, remove the recorder (probably the "cdrom" entry) from /etc/vold.conf.
If that doesn't work, make sure the CD-R drive is perfectly level. Apparently some older (1996-ish) units were sensitive to being tilted at an angle. Some users have had trouble when a CD-R has been on for a while and has overheated, so if you only have trouble when the machine has been powered on for a while, try putting a small fan above the unit to blow air over it.
With some drives, improper SCSI termination can cause this behavior.
For the Yamaha CDR-200/CDR-400, this may be a sign that the drive has broken down and needs to be replaced. See section (5-1-1).
If nothing helps, there's a strong possibility that the drive is mis- aligned and needs to be serviced. This has been known to happen to drives during shipping.
One user with a caddy-based drive reported problems when using the wrong type of caddy. It has to be a Sony-type caddy, which is the kind most commonly found in stores.
The optical power output range of the laser in a low-speed CD-R is between 4 and 8 milliwatts. (By comparison, the read laser runs at about 0.5mW.) High-speed recorders and CD-RW devices use a greater range. At the top end of the scale are DVD-R recorders, which output around 100mW for 4x recording and 200mW for 16X recording. CD-R and CD-RW discs have a section outside the standard recording area called the Power Calibration Area (PCA) that is used to adjust the laser for the brand of media you're using and the speed at which you're recording.
Power calibration errors indicate that the drive is having trouble calibrating the power setting. The most common cause is incompatibility with the media you're using -- if you just switched to a new brand or batch of media, this is a likely culprit -- but it can also be caused by a dirty lens or a dying recorder.
If you're seeing "power calibration area full", it means the recorder ran out of space in the PCA area. There are 99 regions in the PCA area. After 99 attempts to calibrate the power level, there won't be any places left, and the recorder will report an error.
Try a few different kinds of media to see if the problem is an incompatibility between your recorder and the discs you're using. If that doesn't make a difference, there are a couple of things you can do to mitigate the problem. First, you can try recording at a slower speed. The recorder will use a different "write strategy", which usually means a lower power level. Second, if you're storing the discs in a cold place, you may want to try heating them up to slightly above room temperature (placing them near a heating vent works). One user found that this helped.
If all else fails, and the drive is still in warranty, you should have the drive checked by a repair facility. If it's out of warranty, or there's no easy way to have it checked out, you can try cleaning it. See section (3-30).
Some versions of the firmware for the Philips CDD2000 (and HP 4020i) will report a power calibration error if you try to do a 1x write after a 4x read.
It's also good to verify, if your CD recorder is an internal unit, that your power supply has enough capacity to run everything. Recent PCs systems should have a 300W or better power supply.
One user found that his problems went away when he created an image file with Easy CD Creator, quit out of the program, restarted it, and then recorded from the image at a moderate speed. (Doesn't make much sense, but if it works, use it.)
This was observed with a Yamaha CDR-100. The solution is to go into the Adaptec BIOS (hit Ctrl-A during boot), and disable the "support removable disks under BIOS as fixed disks" option and the "boot from CD-ROM" option.
There's a couple of possibilities: either they aren't there, or they're there but you can't see them. Looking at the disc from different machines (e.g. Mac and PC) should give you some idea.
Out-of-date versions of MSCDEX have been known to "forget" certain files when browsing a disc. If you're using DOS or are using the "real mode" drivers from within Win95, make sure you're using the most recent version of MSCDEX.
Old versions of certain CD creation programs would occasionally omit things when asked to burn a large number of files. These problems haven't been reported for some time, however.
If you were burning a multi-session CD, read the next section.
A common mistake when burning a multisession CD is to forget to link the files from the previous session into the current one. This results in a CD where you can see the new files but none of the old, unless you have a program that lets you choose which session you look at.
If you're using Easy-CD Pro for Win31, CD Creator, or Roxio Easy CD Creator v3+, you can load the contents of all the previous sessions, and burn a new session that has all the files you want. This feature wasn't available in Easy-CD Pro 95, which only allows you to link to one previous session.
The files themselves aren't really lost. Most recording software will allow you to extract a track as an ISO-9660 image, and you can use WinImage (section (6-2-2)) to pull individual files out of it. If all else fails, CD-R Diagnostic (section (6-2-6)) claims to be able to recover data from "lost" sessions.
One caution: without something like Roxio's Session Selector, you may not see the last session on the disc anyway. Some CD-ROM drives stop looking for sessions after a certain point.
Good SCSI cables and correct termination are absolutely essential. SCSI bus errors can cause buffer underruns or corrupted data (especially since some vendors ship drives with parity checking disabled).
Bertel Schmitt wrote an excellent article on the ins and outs of proper cabling and termination. The article can be found in text form at http://www.fadden.com/doc/scsi-trm.txt. Granite Digital, a company that makes high-quality cables and terminators, can be found at http://www.scsipro.com/.
If you're using an HP 4020i with the AdvanSys SCSI card, reducing the DMA transfer rate may help.
There are actually two questions here, so I've split them into separate sections. The most common problem is that the audio extracted to the hard drive doesn't quite match the original.
Most problems are due to poor digital audio extraction from the source media. Some CD-ROM drives will return slightly different data every time an audio track is read. Others, like the Plextor line (e.g. 4Plex, 8Plex, and 12Plex, but not 6Plex) will return the same data every time so long as the source media is clean.
The most fundamental problem is that, if the CD is dirty, the error correction may not be able to correct all of the errors. Some drives will interpolate the missing samples, some won't.
Another problem some CD-ROM drives face is "jitter". See section (2-15) for details.
See also section (3-3) on avoiding clicks in extracted audio, and section (5-5) on which CD-ROM drives are recommended.
Suppose you extract the audio track from the copy, and it's an exact binary match of the track you wrote from your hard drive, but the CDs don't sound quite the same. What then?
Most people don't notice any difference between originals and duplicates. Some people notice subtle differences, some people notice huge differences; on better CD players, the differences are harder to hear. Some say CD-R is better, some say worse. While it's true that "bits are bits", there *are* reasons why CD-Rs may sound different even when the data matches exactly.
The most prominent problem is jitter. This isn't the DAE "jitter" described in section (2-15), but rather a timebase error. A good overview can be found in the jitter article on http://www.digido.com/. A brief explanation follows.
Most CD players use a clock derived from the incoming digital signal to drive the digital-to-analog conversion. Even if the CD player gets all of the digital bits accurately, it will produce inferior results if the timing of the bits on the disc isn't precise. Put another way, something has to send a sample to the speakers 44100 times per second, and if it's speeding up and slowing down many times each second your ears are going to notice.
If you play a CD digitally (e.g. by ripping it and then playing it through a sound card), the quality of the CD doesn't matter, because it's the timing of the clock in the sound card that drives the output.
A fancy CD player could provide its own clock to drive the DAC, buffering up bits and playing them out in carefully controlled time. This is tricky though, because when you have two clocks in a system they are likely to drift apart, and you have to deal with buffer underruns and overruns when one outpaces the other. (A man with two watches never knows what time it is, because the watches almost never agree.) The timing from the disc is generally good when considered over a long period, so the challenge to CD player manufacturers is to design circuitry that produces a stable timing signal from a somewhat unstable source.
(This begs the question: does a CD player with anti-shock protection produce better sound? The player has to read the disc at 2x so it can buffer enough data to continue playing even when the CD player is jolted and loses tracking. Such players tend to do *worse* with CD-Rs because the higher read speed magnifies problems with marginal discs, but it's possible that they have less of a problem with jitter -- assuming, of course, that their internal clock is accurate and stable.)
It has been asserted that the clocking of bits on a CD-R isn't as precise as on a pressed CD. Writing at different speeds on different types of media requires adjustments to the "write strategy" (section (3-31)) that can result in individual "marks" being sloppier than at other speeds. This could account for inferior -- or at least different -- sound.
Yamaha believes they have found a partial solution for jitter problems with their Audio Master Quality feature. See section (2-41).
Some people have asserted that *any* two CDs, pressed or otherwise, will sound slightly different. Some claim to hear differences in identical CDs from different pressing plants. The former is silly, but the latter makes sense if one pressing plant is using a less-precise technology.
The manual for the CDD2000 reportedly states that the drive uses 4x oversampling when playing pressed CDs, but switches to 1x for CD-R. This affects the quality of the D/A conversion, and can make an audible difference.
http://www.mrichter.com/cdr/primer/losses.htm has some further thoughts, including a table showing signal level differences.
A paper was reportedly submitted to the Audio Engineering Society, entitled, "An Investigation of the Sonic Differences Between Numerically Identical Compact Discs", by Julian Dunn. Preprint 4339, the 101st AES convention.
An extremely technical introduction to CD reading is available at http://www.tc.umn.edu/~erick205/Papers/paper.html. This may shed some light on why reading audio CDs is difficult, as well as explain concepts like aliasing and dither.
If you are finding your CD-Rs to be noticeably inferior, try different media, different write speeds, a different player, or perhaps a different recorder. There is some evidence that different brands of media and recorders may work better for audio, but in the end it's a highly subjective matter. Some people say CD-Rs sound worse, some people say they sound better (and some people think vinyl records are still the best).
Some recorders don't correctly extract digital audio if the pregap of the first track isn't exactly two seconds. A bug in the firmware causes the drive to start extracting slightly past the start of the track, and stop extracting slightly past the end. This can result in an audible glitch if the music starts at the exact start of the track, and can cause the drive to fail with an error when extracting the last track on the CD.
CDs that start at 00:02:32 (0 minutes, 2 seconds, and 32 blocks) are surprisingly common. The problem can be worked around manually, by looking at the output of Jeff Arnold's freeware TOC program (available from http://www.goldenhawk.com/) and supplying "/start=" and "/end=" parameters that adjust backward by the number of blocks in excess of two seconds.
For example, if the first track started at 00:02:32, you would subtract 32 from the starting and ending Logical Block Addresses.
A better solution is to use a CD-ROM drive that doesn't have this problem (and most likely can extract audio more quickly than the CD-R can).
The Yamaha CDR-100/102 and the Philips CDD2600 are known to have this problem, though it may get fixed by a firmware update. The Ricoh 6200S reportedly does not return the disc's table of contents correctly for these sorts of discs.
Newer recorders, and newer software, should deal with this situation correctly.
The default audio player in Win95 tries to load the entire file into memory. When an extracted track is 40 or 50MB, and you don't have that much RAM, Win95's virtual memory system starts writing pieces out to disk. The disk thrashes, and you get nowhere.
There are several ways around this. If you right-click on the file and select "properties", you will see a "preview" tab. This will play it directly from disk. Another way is to use a different program. One possibility is the Media Player, which is optionally installed with Win95. You can make it the default WAV file player by selecting View/Options from Win95 explorer, clicking on the "File Types" tab, and choosing "Wave Sound". Double-click on Play and change the program name from "sndrec32.exe" to "mplayer.exe", leaving the "/play" and "/close" flags intact.
You can also use a program like CoolEdit, which will let you preview WAV files from the Open File dialog.
The WMA player in more recent versions of Windows should work correctly.
This problem is often experienced by HP7100/7110 users. HP chose to ship packet-writing software with their drives rather than conventional premastering software, leaving users with discs that couldn't be read on a fair number of systems. (The HP7200 is the same drive, shipped with updated firmware and a more complete set of software.)
The following is an excerpt from an Adaptec readme.txt file. It talks about DirectCD, but the problem is inherent in all packet writing solutions:
"When the disc is in the native format used by DirectCD, you will only be able to read the disc on a CD-R device running DirectCD. This is a direct result of the technology used when writing to a CD-R disc. In order to make the disc readable on a standard CD-ROM DirectCD must write certain data to the disc. This provides compatibility with many of the current drives on the market today. Unfortunately, there are still a number of CD-ROM drives that cannot read the packet written media that DirectCD produces. If you experience problems in this area, you should go to System in Control Panel, select Performance, File System, CD-ROM and set the Access Pattern to "No Read-Ahead". If you still experience problems after making this adjustment, it is likely that the CD- ROM drive itself is having problems reading packet written media.If you want to share data between systems, and the remote system isn't guaranteed to have a MultiRead CD-ROM drive, you should write the disc with conventional software.
It should also be noted that there is an industry initiative called MultiRead that addresses these issues and has the support of all the major vendors of CD-ROM and CD-R/RW devices. This initiative will eliminate the above problems and should be available on all new drives."
There have been a fair number of people who have burned a CD-ROM only to discover that, while they can read text files, run applications, and look at graphics, they can't extract from .ZIP archives or run compressed applications (e.g. some "Setup.EXE"s under Win95). A common complaint is a dialog with "the file is not a valid win32 application".
The problem they're seeing isn't just corruption of .ZIP files though. Most kinds of files have a lot of redundancy in them. If a single bit is lost out of a long text file, the chances of it being noticed are very slight. For an application, the chances of it causing a failure depend on where in the file the error falls. For a compressed file, though, every bit is significant, and in a .ZIP archive the CRC has a very high probability of detecting errors. (CRC is cyclic redudancy check. Most file archivers compute a 32-bit CRC on the uncompressed input and store it in the archive. When you extract the files, the CRC is checked to ensure that nothing has been damaged.)
Eliminating these errors could be as simple as replacing a bad SCSI cable. One way to narrow the possibilities down is to try the disc in different readers on different machines. If the same error shows up in the same place, the error was introduced during writing rather than while reading the data back. Another thing to try is to burn the same disc twice. If the data written to the CD-Rs doesn't match the original, but they do match each other, then the errors are happening in the same place every time, rather than at random, so the trouble might be with a driver or firmware instead of a flaky cable or bad RAM.
If a file appears to be getting corrupted on the CD-R, try copying it back to the hard drive and then comparing it to the original. If possible, see if the file is missing large chunks or just has sporadic damage throughout. You can use the DOS "fc" command (e.g. "FC /B FILE1 FILE2") or one of the fancier applications listed in section (3-22).
If you can identify the problem as being with the reader or the writer you may be able to focus on just one part of your system. If the trouble appears to be with your writer, and you can't get it to work, try to move it to somebody else's system and see if it works from there. It's possible, though unlikely, that the CD recorder is flaky.
Whatever the case, the place to start is to check all cables, connections, SCSI termination, L2 cache, and RAM. One user with an otherwise properly functioning system was able to fix the CD-R corruption problems by correcting the RAM timings in the BIOS setup. Use a memory tester, such as "Memtest86" from http://www.memtest86.com/, to look for bad RAM. A couple of others found that their problems went away when they disabled the L2 cache on the motherboard. Sometimes adding a new device will make cables (especially longer ones) turn flaky. Sometimes the flakiness only affects one device. Swapping the cables is inexpensive, easy, and very likely to root out the cause of your problems. Section (4-17) has some tips on SCSI stuff. If your problem is media compatibility, and the errors are a result of the BLER (error rate) exceeding the error correction's ability to fix them, then changing to a different brand of media might help.
One last thing: make sure the original files are valid before you go on a wild goose chase!
There are a few possibilities. First and foremost is media compatibility. Not all players get along with all brands of CD-R media. You need to find a combination of recorder, media, and player that get along. Read section (7-2) to learn more. A CD-R media identifier (like the one listed in section (6-2-9)) can help you be sure that you're trying discs from different manufacturers, but they aren't 100% reliable (section (2-33)).
If you're trying to use CD-RW media, your odds of success are worse than with CD-R. CD-RW discs simply won't play on most CD players.
Another common problem is failing to close the disc at the end of writing. You can't play an audio CD on a common CD player until the session has been closed. You may be able to play it back with the CD recorder though. Also, don't forget that you have to write all of the audio data into the first session of a multisession CD. CD players don't know how to find the later sessions, so tracks written there won't get played.
Sometimes the CD player will spin the disc up but won't start playing it. Sometimes it will have no problem playing the tracks, but will have a great deal of difficulty seeking between tracks or moving fast-forward. Using a different brand of media or a different CD player may produce better results.
If you're getting skips and jumps, make sure that you don't have anti-skip protection enabled. This is usually only available on portable or car players, and you may not be able to disable it on car players. Car CD players are notoriously picky about media. See also section (4-40).
One user with a Jensen car CD stereo was unable to use blanks immediately after recording them. After a couple of days, the discs suddenly started working. This "delayed finalizing" behavior appears consistently repeatable, not a one-time event. Recording at 1x instead of 4x resulted in discs that were immediately usable.
Some media works better at 1x, 2x, or 4x than it does at other speeds. You may find that slowing down or speeding up the recorder helps.
If the disc plays okay at first and starts sounding bad later, or it sounds okay on the first few tracks but gets noisy toward the end of the disc, see section (4-47).
One reader reported that many CD players have a laser power adjustment that can be tweaked to improve things. Fiddling with the insides of devices you don't have manuals for is generally unwise, so don't go looking unless you're desperate.
Finally, remember that you have to write the disc in CD-DA format! If you just write a bunch of .WAV files to a disc in CD-ROM format, it's not going to work in your home stereo.
As with audio CDs, discussed in the previous section, there are several possibilities. The media compatibility issues mentioned above apply to CD-ROM as well.
If you're using CD-RW media rather than CD-R media, you have to be sure that the CD-ROM drive in question is MultiRead compliant. Some older drives are able to read CD-RW media, but most are not. Newer drives should work fine.
If the disc was written using a packet writing application like DirectCD (where you format a disc and then copy files directly to it, instead of creating a disc layout and recording a whole bunch of stuff all at once), some CD-ROM drives will stumble on packet boundaries. Refer to section (4-21) for information and a possible workaround.
If a packet-written disc was closed in ISO-9660 Level 3 format, it won't be usable on systems that don't support ISO-9660 level 3 (e.g. DOS). If the disc was *not* closed as ISO-9660, and is still in UDF, you will need a UDF driver; see sections (6-3) and (6-3-1) for an overview and pointers to free drivers. If the failing system is running Windows XP, see http://support.microsoft.com/default.aspx?scid=KB;EN-US;Q321640& for an article on using UDF discs under XP.
If you put a VideoCD (White Book) into your CD-ROM drive, you will see a bunch of files and directories like you would on any other CD-ROM. In fact, with the appropriate software installed, on some platforms you can double-click on a file to play the video.
In practice, however, the video files are stored on separate tracks, using CD-ROM/XA MODE-2 FORM-2. This allows more data to be stored on a VideoCD, at the price of less error correction. If the video is short enough, you may be able to copy the disc as a collection of files, but some players may be unable to play back selections if the original disc had more than one track.
You need to use a program like Roxio's CD Copier or GoldenHawk's CDRWIN to copy the disc track-by-track, preserving the mode of the original.
If your drive only supports track-at-once recording, you may have trouble copying VideoCDs because the starting address gets shifted when the drive writes a gap between tracks. NTI's CD-Copy (section 6-1-12) gives you the option of dropping the last part of the previous track to preserve the start position of the next track.
Note that MODE-2 FORM-2 holds 2324 bytes of data per sector, so instead of a total capacity of around 650MB, you can put closer to 740MB on a disc. If you don't record the VideoCD data files in the correct format, you will find yourself running out of room. (The extra space is gained by throwing out error correction codes that aren't necessary for video data. Writing ordinary data in this format is not recommended.)
This often used to be a problem with auto-insert notification being enabled when it shouldn't be. See the discussion in section (4-1).
If you're using track-at-once recording, and the actual write is failing when the disc is 100% complete and the TOC is being written, you may be able to solve your problems by using a different brand of media. See the notes in section (4-9).
One person supposedly fixed a similar problem by replacing the power supply in their computer. Apparently the 200W supply wasn't enough to handle everything that was connected to it, and the resultant "brown out" may have been causing problems during writing.
It's possible that the disc has developed a region that can't be erased. More likely is that the software or firmware is acting up. If you're using Easy CD Creator, insert a good CD-RW disc, and start the Erase process. Just before you hit the final "OK" button to start the erase, swap the troubled blank disc in place of the good one.
If this succeeds, you probably ought to run it through the erase procedure one additional time before using it.
Super Blank, from http://www.ping.be/kris-schoofs/, reportedly accomplishes the same thing without requiring a disc swap.
If this doesn't work, there is an (unconfirmed) report that a UV EPROM eraser will do the trick. Experiments have shown that leaving the disc out in direct sunlight for a couple of hours may also help. The resulting disc won't be fully erased, but it may be "blank enough" that you can then use Super Blank to finish the job. (Somebody else has reported that polycarbonate is opaque to UV light, suggesting that the discs should be left label-side-up if this is to work at all.)
If nothing at all works, make a careful examination of the write surface of the disc. It's possible the disc is physically damaged and can't be used.
First off, see section (3-40) for an explanation of the different ways to make a disc look empty. For conventional CD recording, you don't want to format the disc at all.
If it's a CD-RW that you've used before, try erasing it first. If you can't seem to do that either, see section (4-27).
One user with DirectCD 5.01 had troubles that went away by changing the VCACHE settings from min=2048 max=6144 to min=0 max=10240. See section (4-1-2) for information about the surprisingly important VCACHE settings.
It has been reported that some virus scanners, notably TBAV, can interfere with the format process and should be disabled.
This was sent to me by Jac Goudsmit, regarding formatting CD-RW media with DirectCD for Windows 2.0a:
"When [Roxio] DirectCD refuses to format a CD-RW for packet-writing, it's possible that the disc is not completely blank. This may happen because you chose the "quick" option when you last erased it. The quick-erase option only erases the lead-in area to make the hardware and software think the disc is empty. This is fine if you're going to use the disc for "normal" writing as a CD-ROM, audio disc or whatever.
The packet-writing formatter in DirectCD 2.0a however (apparently) requires the disc to be totally empty, so you really have to do a full erase if the disc contained data previously.
BUT: there's another problem: after you do a full erase and shut down the program you erase with (e.g. EasyCD Pro or Easy CD Creator) it's possible that the DirectCD program won't recognize the disc as valid media, and you still won't be able to format it, until you restart the computer.
Unfortunately this means that if you want to start using a previously recorded CD-RW for packet writing, you'll have to wait a total time of at least an hour and a half for the erase and format to complete..."
(Many users had trouble with Win98 shortly after it was released. These problems can still arise if you re-install the original Win98.)
If you're using Easy CD Creator 3, try uninstalling it, rebooting, and then reinstalling it. This seems to fix the problems for the people reporting them. Doing the same for other software may have similar beneficial effects. Apparently ECDC3 installs its own versions of some system drivers (e.g. ASPI), which get overwritten when Win98 is installed. Uninstalling and reinstalling the drivers puts the ECDC3-friendly versions back.
Make sure your ASPI (Advanced SCSI Programmer's Interface) layer is up to date, even if you have an IDE recorder. See section (4-44).
(This refers to systems upgraded from Win95 to Win98.)
This problem has been recognized by Microsoft. The resolution is posted on http://support.microsoft.com/support/kb/articles/q186/2/97.asp.
The basic problem is that, after upgrading to Windows 98, copies of some CD-ROMs (usually copy-protected games) will refuse to run, insisting that you insert the original disc. Microsoft has recommended two methods for resolving this issue. The first is to simply use the original disc.
The second recommendation is to make a new copy of the disc under Win98. Why this works is unclear, and the Microsoft support pages aren't much help. They only say that the behavior is not caused by a bug, but rather "design changes in Windows 98". (It appears that using Win98 to write a new session onto an existing disc will also cure the problem, but if you aren't in the habit of leaving a new session open on copies of game discs, this won't help you much.)
One possibility is that Win98 returns a value for the volume label that is closer to what is actually stored (perhaps there was some sort of character set conversion or truncation going on in Win95). Copy protected games often check the volume label as a way of obstructing inexperienced software pirates.
Start with http://www.mrichter.com/cdr/primer/udf.htm to get an understanding of what DirectCD is doing.
A popular way to screw up DirectCD's UDF handling is to remove the disc without letting the software finish up. You can accomplish this by rebooting while it's working, attempting to disable it by doing something other than uninstalling it (see section (3-45)), or by turning off auto-insert notification.
If you have DirectCD 2.x, you may be able to recover the data with the included Scan Disc utility. CD-R Diagnostic (6-2-6) may also be able to recover data.
Rule of thumb: don't delete data off your hard drive until the disc is finalized and verified readable. Too many bad things can happen when writing to a disc.
When attempting to copy certain discs, Easy CD Creator (as of v3.x) will say something like:
"The current track contains more than 100 form transitions. Easy CD Creator cannot handle more than 100 form transitions on a single track. The disc cannot be copied."This appears to be a form of copy protection, where a disc uses both FORM-1 and FORM-2 on a CDROM/XA MODE-2 disc.
One user reported that this only happens when trying to copy a Playstation game by first copying the tracks to the hard drive. If you make a copy directly from one disc to the other, the errors won't occur.
According to Roxio, the message can also occur if the source drive is reporting more than 100 tracks on the disc, or if the source drive is defective in some specific way.
You may have a bad installation of a CD recording program like DirectCD. When you insert a blank disc, the software tries to identify it to give you the opportunity to format it for packet writing.
If you have packet software like DirectCD or PacketCD installed, try uninstalling it and see if the problem goes away. In some cases you might need to get rid of windows\system\iosubsys\scsi1hlp.vxd manually.
Not all DVD players can handle CD-R media. See section (2-13).
Some players that don't work with CD-R discs will work with CD-RW discs. If you're having trouble, try CD-RW media instead.
If CD-R Diagnostic (6-2-6) can't help you, there are places that might be able to. Some examples:
Some applications, notably Easy CD Creator, can only do very simple conversions on audio files. If you are trying to create an audio CD, but the WAV file isn't 44.1KHz 16-bit stereo PCM, you will have to convert it to that format with something like Cool Edit (section (6-2-14)) before you do the write.
Sometimes a Windows system will get into a state where it thinks that a CD-R or CD-RW data disc is an audio CD. This is very peculiar, since the CD-ROMs aren't "enhanced" discs with both audio and data content. In some cases the problem only happens with a CD recorder -- a CD-ROM drive in the same machine will work correctly -- or vice-versa.
One situation where this is reported to occur is with a JVC XR-W2080 with v2.06 firmware (or an equivalent OEM version). If you have the Roxio UDF reader loaded, whether manually or as part of installing DirectCD 3.x, the problem will occur. Removing the UDF reader, either with Add/Remove Programs or renaming \Windows\System\Iosubsys\Udfreadr.vxd, is said to fix the problem.
Another occurrence has been reported with Toast 3.7 on a Mac. If a disc was recorded with Toast as CD-ROM/XA instead of CD-ROM, Win98 would see the disc as audio. Win95 and WinNT worked fine on the same disc.
One user found that replacing the IDE cable made the problem go away. Another found that using MODE-1 rather than MODE-2 helped (check the advanced recording options in your software).
Another user got the problem to go away by uninstalling "Wavelab".
Somebody else found that the problem went away on a SCSI device when he disabled wide negotiation and limited the data rate to 16MB/sec.
You are most likely running into copy protection. The game publisher has placed "unreadable" sectors on the disc, in an effort to confound disc duplication programs.
Instructions for making "backups" of copy-protected games can be found on the web. See also section (3-39).
If you don't believe the disc is protected, then it might simply be dirty or scratched. You can try to clean the disc -- use a lint-free cloth, wiping from the center out -- or see section (7-12) for notes on scratch removal.
This is a situation where recording discs proceeds without difficulty, but the system hangs when you tell it to halt or restart. One possible culprit is anti-virus software. Try disabling it and see if the problem goes away.
When a CD player is playing a disc without any sort of anti-skip protection, it spins the disc at 1x, and attempts to correct whatever errors it gets. If it can't correct them, it does the best it can and keeps going.
When an anti-skip feature (such as Sony's "ESP") is in use, the disc is played at a faster speed (perhaps 2x), and when uncorrectable errors are encountered, the failed section is re-read.
CD-R discs are generally harder to read than pressed discs, so there is a greater likelihood of encountering uncorrectable errors. In some cases a player may get stuck re-reading a particular section, and the playback will have lots of skips and jumps as a result.
The skip protection feature can usually be turned off on portables. On car players you may have to find a brand of media that works better.
Make sure the software you're using supports Win2K or WinXP. Don't assume that, just because it runs, everything will work correctly. You may need to update to a newer version.
Under Win2K, you may need to be running as an Administrator equivalent to record. The reasons for this appear to be access permissions on the device, on certain registry keys, or both. Similar problems may arise under WinXP.
Installing Windows Media Player 7 in Win2K may mess up Easy CD Creator and DirectCD. One solution is to uninstall and reinstall both, and make sure ECDC is at 4.02c or later and DirectCD is at 3.01c or later. A simpler solution involves a registry fix. For a complete discussion of the problem, go to http://ask.adaptec.com/, and in the "Search all Products by Keyword or Article Number" section enter "000726-0003", click on "Article #", and press the "search" button.
IDE recorders may need to be the master device when used with ECDC under Win2K. If you are having trouble with an IDE recorder, and it's not set up as the secondary master, try configuring it that way.
Running ECDC v3.5c under Win2K is not recommended. Only Version 4.02 and later are officially supported. For WinXP, you need version 5, and even then you'll probably have trouble. See also section (4-49).
Installing WinXP Service Pack 1 may cause problems with DirectCD. The solution is to uninstall and re-install DirectCD after installing the WinXP SP1 update.
A few people were able to fix problems by disabling the in-built CD recording features of WinXP. This can be turned off for each drive by right-clicking on the drive in My Computer, selecting Properties, then clicking on the Recording tab and disabling the appropriate checkbox. A more thorough approach is to open the "Administrative Tools" control panel and disable the "IMAPI Burning Service".
See also Microsoft Knowledge Base article #324129, "HOW TO: Troubleshoot Issues That Occur When You Write Data to a CD-R or CD-RW Optical Disc in Windows XP", at http://support.microsoft.com/?scid=kb;en-us;324129.
This is the expected behavior when formatting CD-RW media for use with Roxio's DirectCD packet-writing software. CD-RW discs are formatted with fixed-size packets, which takes up more space but allows you to erase individual files. With variable-size packets, you get to use more of the space on the disc, but when you delete a file it is simply marked as gone. The space is still in use.
To use variable-size packets on a CD-RW with DirectCD, format a CD-R with DirectCD and then do an image copy from the CD-R to the CD-RW.
Packet writing programs from other companies may work differently.
Don't forget that it is only necessary to format a disc if you want drive-letter access. Conventional pre-mastering and creation of audio CDs should be done on unformatted discs. See section (3-40).
There are many possible reasons for this. Most people are quick to blame the software, but sometimes the problem is elsewhere in their system.
First things first: make sure you have the latest version of the software that is available. Perhaps you have found a bug that has already been fixed.
If you have overclocked your system, or tweaked it in a way that gains performance at the expense of reliability, un-tweak it and try again.
Under Windows, make sure your ASPI layer is up to date. See (4-44).
Also under Windows, look for \Windows\System\Iosubsys\scsi1hlp.vxd. If it's there, rename it to "scsi1hlp.vx_", so it won't get loaded. Reboot and try again. (This file is required for compatibility with some old SCSI hard drives. Occasionally it can intefere with other things.)
If your system looks good, contact the appropriate customer support center. If you bought the software retail, contact the company who developed the software. If it came with something else, and was distributed as an "OEM" version, you may need to contact the vendor you got it from instead (see section (6-8) for an explanation).
See http://www.mrichter.com/cdr/primer/aspi.htm for an introduction to ASPI.
Many people have solved problems by updating their ASPI layer. In the past, it has been the first thing that customer service would ask you to check. Adaptec makes it easy with a program called ASPICHK, which used to be available from http://www.adaptec.com/support/faqs/aspilayer.html. It seems to be gone now, but http://www.mukappa.com/ had copies available under "Tools --> ASPI tools".
At any rate, according to Roxio, as of version 4.02 of Easy CD Creator (ECDC), the ASPI layer is no longer used by their product. The necessary bits are included in the application, so there's no need to check or update the layer.
For non-Adaptec owners, there is a program (of questionable legality) called "ForceASPI" that forces the Adaptec ASPI layer to install. Usually Adaptec will ask sites to remove it, so it's a bit of a moving target. http://www.mindspring.com/~tburke1/aspi.htm had a list of active sites, and it can occasionally be found with a Google search. You can also try http://aspi.radified.com/.
Some other software uses and/or modifies ASPI -- poorly. Known examples are some USB SmartMedia readers and the Creative Labs Infra system. Updating the ASPI layer when one of these devices is present may be unwise.
It's unclear what interactions Windows ME has with ASPI.
As of September 2001, the Adaptec ASPI layer causes problems on Win2K and should not be used. The LSI "w2kaspi" layer may work better; it can be found at http://www.lsilogic.com/support/support+drivers/scsi/w2kaspi.html. [At last check, the links in the page were broken.] WinXP may have similar problems.
This problem has been reported by a number of people. The cause is unclear. This has been known to happen suddenly to otherwise fully functional CD recorders.
Models where this has been seen:
If the disc is recognized but won't erase or format, see section (4-27).
One possible source of difficulty is there are different blanks for "slow" recorders (1x - 4x) and "fast" recorders (4x-10x). The disc manufacturers had to change the way the discs were made to accommodate recording speeds beyond 4x, but older recorders didn't work with the newer disks. The "fast" blanks have the ATIP information in a slightly different place so that "slow" recorders won't recognize them.
It is possible for some 4x-capable "slow" drives to use the "fast" blanks with a firmware upgrade, but there is no advantage to doing so (assuming you can still find "slow" CD-RW blanks).
The "fast" blanks are now being labeled with a "High Speed CD-RW" logo.
More recent drives can use 12x and 24x CD-RW media.
A not-uncommon complaint is:
"I've made lots of audio CDs. They sound fine in my computer or home CD player, but when I put them in the car they have lots of static."
A variation on the theme:
"...the static is only on the last few tracks."
Or, more rarely:
"...the discs sounded fine for a couple of weeks, and still sound fine on most players, but they sound really bad now in the car. The more I played them the worse it got, to a point."
There are a few things going on here. First and foremost is media compatibility. The combination of recorder, player, and media just isn't working. Unless you're willing to change your player, the easiest thing to do is change the brand of media you're using.
The reason tracks out past the N minute mark (typically 40) sound worse might be due to speed changes. For 1x audio playback the player is in CLV mode, so the disc is spinning more slowly near the outside of the disc. (You'd think that'd make it easier, not harder. Go figure.)
You should make sure that it's a problem with writing and not with reading tracks near the edge. Try writing the tracks in a different order. A good way to do this is to extract the tracks into WAV files with a reliable DAE program (EAC, from section (6-2-12), works well). Play them from the hard drive to make sure they extracted well, and then record them onto two CD-Rs, using a different track order for each. If the problem is always on the last track then the disc is being recorded poorly.
The slight deterioration of the media after being played a few times isn't expected, but does seem to happen with some discs. It appears that the compatibility between the discs and the player is marginal to begin with, so a slight degredation in error rate on the disc results in a dramatic increase in noise during playback.
The ISO-9660 standard allows discs with directories nested 8 deep. If you try to go deeper than that, you may have trouble reading the files. Win2K and WinNT4 seem to work, but Win98SE doesn't.
Programs like "mkisofs" can use the Rock Ridge extensions to work around the problem. Directories are "re-rooted" at a higher level, and invisible links are created from the deeper directories. Unfortunately, Windows still doesn't support Rock Ridge.
The UDF format, used by packet writing applications, may (?) allow deeper directories. However, not all systems can read UDF discs.
There is a problem with Roxio DirectCD 3.01/3.01c and Roxio Easy CD Creator version 4.02c and 5.01. If you uninstall them from WinXP or Win2K, your CD-ROM drive may stop working. It appears that VOB InstantCD/DVD and Nero InCD can have the same effect.
Any CD-ROM drives will be inaccessible from My Computer, and the device manager will show a "code 31", "code 32", or perhaps "code 19" message for the drives.
The page at http://support.microsoft.com/support/kb/articles/Q270/0/08.ASP describes the symptoms and the resolution of the problem.
Somebody described this as listening to songs recorded by Alvin and the Chipmunks. What's happening is the software used to uncompress the MP3 files is doing a poor job, and the uncompressed data is effectively being recorded at a lower sample rate. When the CD player tries to play it back at 44.1KHz, it sounds like the artists are inhaling a crude mixture of amphetamines and helium.
This has been reported with Easy CD Creator v4.05 and v5, NTI CD Maker 2000+, and something called Orion Liquid Burn.
The work-around is to expand the MP3 files into 44.1KHz 16-bit stereo PCM WAV files on your hard drive, and record from those instead of from the MP3s. By using a decoder such as WinAmp (http://www.winamp.com/)
Sometimes, when trying to copy files onto a disc from Windows explorer, you get a message to the effect that it can't create or replace a file because access is denied or the disc is full. Some not-so-helpful suggestions about checking write protection and making sure the file is not in use are offered.
This most often happens when trying to use DirectCD with an unformatted disc. A common way to cause this is to disable the DirectCD user interface with msconfig or a similar utility (a mistake -- see section (3-45)), which prevents the "do you want to format this disc" dialog from coming up.
The solution is to let DirectCD format the disc. If you don't see the CD icon in the system tray (usually the lower-right corner), you will need to re-enable it. Under Win98, click on the Start button, select "Run...", type "msconfig", and click "OK" to bring up the System Configuration Utility. Now click on the Startup tab and make sure that anything with the word "DirectCD" in it is enabled. Under Win2K, click on Start, Settings, Control Panels, Administrative Tools, then Computer Management. When the program opens, in the left-hand pane click on System Tools, System Information, Software Environment, then Startup Programs, and make sure DirectCD is present. If not, you may need to re-install.
If the above doesn't seem to help, or you're not using DirectCD, you may be able to manually format a disc. How you do this depends on what software you're using. For example, HP DLA has a utility available from their CD recording application that lets you format a disc or close it to ISO-9660 format.
See section (3-40) for more information on formatting CD-R and CD-RW media.
In some rare cases, after formatting a CD-R or CD-RW disc for packet writing, Windows still claims the disc is full when you try to copy files onto it, or complains that the disc is "locked or protected". This can happen after files have already been copied onto the disc.
This error message can apparently also occur when trying to copy files *from* a CD-RW that has been previously written to.
The problem is rare and isn't well understood. It has been reported with DirectCD 3.x (part of ECDC Deluxe 5.x) under Windows XP. Another instance of "locked or protected" was reported under Win98. In any event, start by checking the "msconfig" situation described above. This *might* also be a media compatibility issue, so if it happens it might be worthwhile to try different brands of media.
If the disc was closed to ISO-9660 format, you will need to reopen it.
If the disc was created with a packet writing program (like DirectCD or HP DLA), it will either be in UDF or ISO-9660 Level 3 format. Either way, you're not going to be able to see files on the disc from DOS. You need to use a more modern OS, such as Windows or Linux, or create the disc with a conventional premastering application like Nero.
Some backup programs, such as Symantec Ghost, use packet writing when backing up to CD-R. The software runs under DOS, but uses a special driver to create and access the backup data. You can see the files from Windows, but won't be able to get at them from DOS.
The numbers after the model name (e.g. "CDR-102 (4x2/512K)") refer to the read and write speeds of the unit and the size of the write buffer. "4x2" would be a double-speed writer that's also a quad-speed reader. If it just says "?x2", the write speed is double-speed and the read speed isn't known (but presumably is at least 2x). Buffer sizes written with a '+', e.g. "2MB+", indicate that the buffer can be expanded further.
If the recorder can write to CD-RW media, the specification will include a third value, e.g. "6x4x2/1MB" would be a drive that reads at 6x, writes to CD-R media at 4x, and writes to CD-RW media at 2x.
Some manufacturers present the speed ratings in a different order, often write/rewrite/read. Some drives that support reading of DVD-ROM will be written write/rewrite/read/dvd-read. There is no standard approach.
Many units are repackaged versions of other manufacturer's devices, sometimes with slight changes in the firmware. Value-added retailers have been known to switch to a different manufacturer's drive without notice, so don't assume that everything here is accurate.
The interface is listed for each drive. "SCSI" means any form of SCSI (SCSI-2, SCSI-3, wide, narrow, ultra, etc). IDE means any ATAPI interface (e.g. Ultra-DMA/33). USB (1.x or 2.x), parallel-port, FireWire, and PCMCIA refer to interface styles for external drives (which are usually just internal ATAPI devices placed inside an enclosure with a power supply and an ATAPI converter).
Many of the models listed have been discontinued in favor of newer models, and some of them have yet to be released, so you will probably not be able to find all of the models listed here for sale.
If you're new to SCSI, take a look at the comp.periphs.scsi FAQ, http://www.faqs.org/faqs/scsi-faq. It covers both novice and advanced questions. If you want specs, try http://www.t10.org/.
A wealth of information on Enhanced IDE and other storage technologies is available from http://thef-nym.sci.kun.nl/~pieterh/storage.html and http://www.faqs.org/faqs/pc-hardware-faq/enhanced-IDE/part1/. If you want to debate the merits of SCSI vs EIDE, please read http://thef-nym.sci.kun.nl/~pieterh/eide-vs-scsi.html.
Some brief notes: ATA (AT Attachment Interface) is the official name for IDE (Integrated Drive Electronics) interfaces. ATAPI is the ATA Packet Interface, commonly used for controlling CD-ROM and tape devices. The ATA-2 changes grew out of vendor-specific "Enhanced IDE" implementations. There have been subsequent enhancements (ATA-3, ATA/ATAPI-4, etc).
There are no absolutely perfect recorders, but some drives are better than others. The best are listed below, and the risky propositions are identified with "CAVEAT EMPTOR" warnings in the individual sections. In cases where a unit is built by company A and repackaged by company B, the warnings are listed with the original manufacturer (company A).
http://www.storagereview.com/ has links to reviews of storage devices, including CD recorders. http://www.cdrlabs.com/ has reviews of both hardware and software products.
This section used to list specific models that were highly regarded. The manufacturers are coming out with new models so quickly that it's impossible to keep up in an FAQ that is updated monthly. The list of older models is below. See section (8-4) for a list of sites that carry news articles about newly released products.
As of late 2001, the most commonly recommended manufacturers (in no particular order) were:
If you have specific needs, you should verify with the manufacturer that the drive will do what you want. All computer-based recorders can create audio CDs and CD-ROMs, but some have additional features and some are just plain better at it. If you want a drive that works well with a specific piece of software, e.g. CloneCD (6-1-49), then you should check the web page for that software to see which drives they recommend.
Some older models that would be worth having are listed below. As of October 2001 this list is no longer being updated.
The model numbers are important! Sometimes the older or newer models from the same manufacturer aren't as good. The units listed were considered independently from the software that they were bundled with, and it may be necessary to buy additional software to get the full value from the drive.
External drives were traditionally preferred to internal drives because of heat problems, but this is only a minor concern for current models. External models do have the advantage that they can be moved between machines, and even between platforms. Most if not all SCSI models will work on both Macs and PCs, as should USB recorders.
I'm not currently listing stand-alone recorders like the "CD Blaster" or "CD Dupe-It", which are boxes with a CPU, CD-R, and hard drive that can duplicate CDs without tying up a full machine. Most of these low-end CD production boxes are off-the-shelf hardware and software packaged into a single unit, so listing them separately doesn't make much sense. Besides, they're not of much interest to the average user. Interested users can find some relevant URLs in (5-19).
See http://yamaha-it.de/ (was http://www.yamaha-yste.com/)
CDR-100 (4x4/512K;SCSI)[ Yamaha departed the optical storage market in February 2003. ]
CDR-400 (6x4/2MB;SCSI; 'c' is caddy, 't' is tray, 'x' is external)
CRW-4416 (16x4x4/2MB; 'S'=SCSI, 'E'=IDE)
CRW-8824 (24x8x8/4MB; 'S'=SCSI, 'E'=IDE, 'F'=Firewire, 'X'=external)
CRW-2100 (40x16x10/8MB; 'S'=SCSI-int, 'SX'=SCSI-ext, 'E'=IDE, 'IX'=Firewire)
CRW-2200E (40x20x10/8MB; 'SX'=SCSI-ext, 'E'=IDE, 'IX'=FireWire, 'UX'=USB)
CRW-3200 (40x24x10/8MB; 'SX'=SCSI-ext, 'E'=IDE, 'IX'=FireWire, 'UX'=USB)
It has been reported that the CDR-102 is the same mechanism as the CDR-100, but with the 4x writing feature disabled. There is no known way to convert it into a 4x writer. Similar speculation has been made about the CDR-200 and CDR-400, and in fact some people have claimed success. Learn all about R621 at http://www.geocities.com/SiliconValley/Bay/7023/index.html (or http://home.t-online.de/home/christoph.dittenberger if you prefer German). It may also be possible to convert a 2260 into a 4260 with the same method, as well as the 2216 into a 4416.
Yamaha CDR-100 and CDR-102 units have problems doing digital audio extraction on some discs. See section (4-19).
Yamaha CDR-100s with firmware version 1.08 may experience problems when recording audio (e.g. a click at the end of tracks recorded with the "copy prohibit" flag set to "off"). Upgrading to version 1.10 is recommended. Since the CDR-100 and CDR-102 units don't have flash ROM (and apparently the upgrade involves more than just changing a ROM chip), the drive needs to be sent back to the dealer for the upgrade.
The CDR-100 reportedly works best when writing in 4x mode, and may produce poor results when used to write at 2x or 1x.
The current firmware versions for the older Yamaha drives is v1.12 for the CDR-100 and v1.01 for the CDR-102. The change was to "allow mastering in Blue Book specs". If you aren't having problems, don't get the upgrade. The Yamaha CDR-400 is somewhere around 1.0g.
The CDR-400 is flash upgradeable, and supports packet writing. The tray on the CDR-400 has been described as "flimsy". The tray eject moves quickly for the first half and then slows considerably; this is normal.
The CRW-4001/CRW-4260 runs rather hot. External units or extra cooling fans are recommended.
Some older Yamaha models apparently don't do disc-at-once recording. However, they will do session-at-once (SAO), which is as useful for most things and essential for multisession mixed audio and data discs. With the right software this isn't a problem.
CAVEAT EMPTOR - Yamaha CDR-200/CDR-400. Reports of units breaking down after a few months have been persistent. It appears that, unless the units are kept well-cooled, they will start rejecting discs after a month or two of use. The drives work very well otherwise, and one customer was told that the CDR-400AT model was a sturdier version.
(It may be possible to fix the drive by tightening some screws and adjusting some poorly-seated heat sinks on chips.)
CDW-900E (2x2/3MB:SCSI)The CDW-900E has a separate connector that allows multiple "slave" drives to be daisy-chained, allowing multiple CD-Rs to be written in parallel.
CRX100E/CH (24x4x2/1MB;IDE) and CRX100E/X (6x4x2/1MB;USB)
CRXP-90MU (24x24x10/8MB;USB2.0, also reads DVDx8, portable)
CRX1600L "i.LINK" (32x12x8/4MB;FireWire)
CRX175A/A1 (40x24x10/2MB;IDE, /A2 is USB)
DRX120A (32x12x10/2MB;IDE, DRX120L is ext. FireWire, also writes DVD+R/RW)
DRU128A (32x12x10/2MB;IDE, also writes DVD+R/RW)
DRU500A (32x24x10/8MB;IDE, also writes DVD+R/RW and DVD-R/RW)
CRX195A1 (48x40x12/2MB;IDE, CRX1950U is external USB2.0)
CRX210A1 (48x48x12/2MB;IDE, CRX2100U is external USB2.0)
MPD-AP20U (24x24x10/?MB;USB2.0/1.1, also reads DVDx8 and plays DVD to TV)
The Spressa 9211 is a 920 in an external case, the 9411 is a 940 in an external case, and the 9611 is a 926. The 940S drive is actually a 924S; the 940S designation refers to the complete bundle (software, cables, etc). Looks like each unit can be referenced by three different numbers.
Some people have criticized the CRX100E for being unable to write more than about 78 minutes on an oversized (e.g. 80-minute) blank, and being unable to "overburn" a disc without resorting to swap tricks. It appears that firmware v1.0n removes this limitation.
Sony drives have a special "recover" feature, accessible from programs like Easy-CD Pro '95. This allows recovery of the CD-R media after certain classes of failed writes.
All Sony drives can do packet writing.
Firmware for some models can be hard to find.
CAVEAT EMPTOR - CDU926 and CDU928. Believe it or not, the CDU926 and CDU928 don't support disc-at-once recording (see section (2-9) for a description). Instead they use "variable-gap track-at-once", which allows TAO audio recordings with barely perceptible gaps between tracks. Some popular software packages aren't as useful when disc-at-once isn't available, so people considering these drives should carefully consider how they plan to use them.
(All other Sony units do support DAO.)
See http://tech.smartandfriendly.com/ (some ROM upgrades)
CDR1002 (2x2/1MB;SCSI, based on the Sony CDU920S)All models are recorders built by major manufacturers, repackaged and supported by Smart & Friendly.
CDR1004 (4x2/512K;SCSI, based on the Yamaha CDR-102)
CDR2004 (4x2/1MB;SCSI, based on the Sony 940S)
CDR2006 "Pro" (6x2/512K;SCSI, based on the Sony 926S)
CDR2006 "Plus" (6x2/1MB;SCSI, based on the JVC XR-W2020)
CDR4000 (4x4/512K;SCSI, based on the Yamaha CDR-100)
CDR4006 (6x4/2MB;SCSI, based on the Yamaha CDR-400)
CD-RW226 "Plus" (6x2x2/1MB;SCSI, based on the JVC XR-W2042)
CD-RW426 (6x4x2/2MB;IDE, based on the Yamaha CRW-4001/4260)
CD SpeedWriter 4012 (12x4/1MB;SCSI, based on the Teac CD-R55S)
CD SpeedRacer (16x4x4/2MB;SCSI, based on the Yamaha CRW-4416S?)
CD Racer 2x2x24 (24x2x2/2MB;IDE, based on the JVC XR-W2080)
CD SpeedWriter Plus (24x4x2/2MB;IDE (SCSI for ext), based on the JVC XR-W4080)
CD TurboWriter (24x6/2MB;SCSI, based on the Teac CD-R56S)
CD Rocket 8020 (20x8/2MB;SCSI, based on the Sanyo/Caravelle CRD-R800S)
CD Pocket RW (20x4x4/2MB;PCMCIA-2, based on ??)
CD Rocket RW (20x8x2/2MB;SCSI, based on ??)
CD SpeedWriter RW (24x4x2/?MB;SCSI, based on JVC XR-4424?)
CD TurboWriter RW (24x6x4/2MB;SCSI, based on Ricoh 7060A?)
CD CpeedWriter 32 (32x4x4/2MB;SCSI, based on Teac CD-W54E)
CD Rocket Mach 12 (32x12x4/4MB;SCSI, based on Sanyo CRD-RW2?)
CAVEAT EMPTOR - the company apparently went bankrupt in mid-May 2000. See the article at http://www.zdnet.com/zdnn/stories/news/0,4586,2597858,00.html. The web page was still running as of August 2000, but got changed to a pointer to justdeals.com after JustDeals bought up S&F's inventory.
See http://www.geocities.com/SiliconValley/Bay/6893/ (2600/3600)
CDD522 (2x2/2MB;SCSI)The CDD521 (2x2/256K) is an ancient model; if you use one, the firmware upgrade is strongly recommended (but nearly impossible to find these days). Some information that may be of use to CDD521 owners can be found at http://www.fadden.com/doc/cdd521faq.txt.
CDD3600 (6x2x2/1MB;SCSI) and CDD3610 (IDE)
CDRW200 (24x2x2/2MB;IDE, based on JVC XR-W2080? repackaged CDD3801?)
CDRW400 (16x4x4/2MB;IDE, based on Yamaha 4416E)
The Omniwriter/26 and /26A appear to be repackaged Ricoh 6200 and 6200I OEMs. In Europe, the 3600 is packaged in a kit as the PCA350RW, the 3610 as the PCA362RW, and the 3610 with a parallel-port interface comes as the PCA363RW. The CDRW400 might be packaged as the PCA460RW.
The CDD522 does not support reading of subcode-Q data. The CDD521, CDD522, and Kodak-labeled PCD225 have a sensor that can read the barcode data from the inner ring on a CD.
See the HP section for comments about the CDD2000 firmware. The firmware is kept in flash ROM, so it can be updated with software obtainable over the net. You should be at version 1.25 or later for best results.
Digital audio extraction may not work correctly at higher than 2x on the CDD2600, especially near the end of the disc. Philips has acknowledged that audio CDs and packet-written CDs may not read correctly at 6x, but many users have had problems at 4x as well. It may also suffer from the block offset problem described in section (4-19). The CDD2600 supports packet writing, but is NOT flash upgradeable.
The CDD2600 may share the HP 6020i's difficulties with pressed CD-ROMs that have a small amount of data on them.
The initial release (firmware v1.0) of the 3610 was unable to create audio discs reliably using disc-at-once recording. Firmware v2.02 fixed this and some other problems.
Philips' drives, notably the CDD2600, have been shown to hang on some Amigas if SCSI disconnect is enabled and you try to read the session information from a multisession CD. Philips does not believe this problem happens on PCs, and consequently has declined to investigate further. If you are experiencing hangs when examining multisession CDs, try turning SCSI disconnect off for the CD recorder.
CAVEAT EMPTOR - CDD2000. Some users of Philips CDD2000 and derivative units (like the HP4020i) have reported that the drives went bad over a short period of time, often 1 to 3 months. While these cases represent the minority of users, reports have been persistent. People with the technical skills (and bravery) required to replace a spring and/or lubricate inside the unit have reported good results (see section (4-10) for details). If you buy a CDD2000-based unit -- of which there are many -- be sure the dealer or manufacturer is aware of this problem and is willing to fix or exchange the drive should it arise.
A class-action lawsuit was filed against Philips on behalf of owners of the CDD2000 and CDD2600. The case was eventually settled, with Philips agreeing to make restitution.
4020i (4x2/1MB;SCSI, based on the Philips CDD2000) (#C4324)The 7110 is identical to the 7100, but comes with an extra piece of software and is only available in the USA. The 7200 is a 7100 with updated firmware (2.x) and Easy CD Creator included. The 8110 is the same as the 8100 but with a bunch of extra software; ditto for 8210 vs 8200. The 6020ep appears to be the external SCSI drive with a parallel-to-SCSI converter. It's usable as a SCSI device as well. The 71XXe drives are 71XXi drives with a parallel-to-IDE converter. The 7500 series is often packaged as 7550 or 7570 (though these are now listed as having only 1MB of buffer, so it's not clear what's going on).
6020 (6x2/1MB;SCSI, based on Philips CDD2600; i)nt, e)xt, p)arallel) (#C4325)
7100i/e (6x2x2/1MB;IDE, based on Philips CDD3610; 'i' is IDE (#C4353A),
'e' is parallel (#C4358A))
7500i/e (24x2x2/2MB;IDE, see note below, parallel 'e' model is 6x2x2)
8100i (24x4x2/1MB;IDE, based on the Sony CRX100E)
8200i/e (24x4x4/2MB;IDE, based on a Sony CRX120E; 'e' is 6x-read USB)
8250i (24x4x4/2MB;IDE, see note below)
9100i (32x8x4/4MB;IDE, see note below)
9200i (32x8x4/4MB;SCSI, based on Sony CRX140)
9300i (32x10x4/4MB;IDE, based on Sony CRX145E)
9500i (32x12x8/4MB;IDE, based on Sony CRX160E?)
9600i (32x12x8/4MB;SCSI, based on Sony CRX160S?)
9700i (40x16x10/8MB;IDE, based on ??)
9900i (32x12x10/2MB;IDE, reads DVDx8, based on ??)
cd12i (32x12x10/2MB;IDE, based on ??)
cd16i (40x16x10/2MB;IDE, based on ??)
cd24i (40x24x10/2MB;IDE, based on ??)
dvd100i (32x10x12/2MB;IDE, writes DVD+RW, based on Philips ??)
There are indications that HP shipped two different drives as the 8250, both with the same read and write speeds. The first was the Philips CDD4201, identifiable by about 18 tiny horizontal indentations along the bottom of the face, with a hinged "drawbridge" loading door. The second was the Sony CRX120E, which has 4 horizontal indentations along the bottom of the face, and no hinged door. The popular consensus is that the Philips versions are problematic. It may be possible to tell the boxes apart using a code on the barcode label: C4464A for Philips, C4464B for Sony. (It appears there may even be a third variety: HP is rebadging Mitsumi 4804TE in their Pavilion 6648C computers. There doesn't appear to be an HP model number associated with the drive though, so it may not actually be sold as an 8250.) It now appears that some 8250i drives are 32x4x4/4MB; these are actually Sony CRX140E drives (32x8x4/4MB) with firmware that limits them to 4x recording. It has been reported that, if you can get the HP9100i firmware onto the drive, it will record at 8x.
There are similar indications for the 7500, which appears to have originally been a JVC XR-W2080, but is now a Sony CRX100E with a reduced maximum write speed. Drives based on the Sony mechanism can reportedly be flashed with the Sony CRX100E firmware update and upgraded to 4x recording.
Most 9100 uints are based on the Sony CRX140, but there are indications that units identifying themselves as "9100b" is actually a Goldstar CED-8080B.
The initial release of the 7100/7110 was unable to create audio discs reliably with disc-at-once recording. The 2.02 firmware upgrade fixes the problem.
Some people have criticized the 8100i (same as Sony CRX100E) for being unable to write more than about 78 minutes on an oversized (e.g. 80-minute) blank. It appears that the Sony v1.0n firmware upgrade removes this limitation, but the upgrade was never made available for the HP drive. Some users have had success flashing the drive with a "hacked" version of the Sony firmware, but this can be dangerous (see warnings in section (5-24)).
If you are having trouble getting the 7100e to work with your parallel port, see http://www.hp.com/isgsupport/cdr/tech/7100/par95.html for some important configuration advice. If your BIOS is configured to use address 03BCh, you should change it to 0378h or 0278h.
It appears that discs written with a 7110 can't be read on a Toshiba XM6002B. Other models of CD-ROM drives, including other Toshiba models, work fine. CD-Rs written on other CD recorders work fine with the Toshiba. The 3.01 firmware upgrade fixes this.
The HP 4020i got off to a rough start because of buggy firmware and problems with the AdvanSys SCSI controller shipped with the drive. Four firmware upgrades have been made available so far (v1.20, v1.25, v1.26, and v1.27), and most but not all problems with the firmware have been eliminated. HP recommends that users with the v1.20 or later firmware who aren't having problems should NOT get the upgrade. Contact HP tech support for more information.
The comments about digital audio extraction problems and the CDD2600 apply to the 6020i as well. Unlike the CDD2600, the 6020 apparently does not support packet writing. The firmware is not flash upgradeable. (As it happens, the SCSI ID string *can* be changed, and it *is* possible to make the unit think it's a CDD2600. A representative from Adaptec has warned that the procedure could cause problems later on, however.)
The 6020 with v1.07 firmware also has trouble reading some pressed CD-ROM discs, notably single-track CD-ROMs with less than 27MB of data.
An unofficial HP 4020i FAQ maintained by Greg Volk can be found at http://www.cd-info.com/CDIC/Technology/CD-R/HP-FAQ.html.
Drivers, software, and firmware upgrades are available from ftp://ftp.hp.com/pub/information_storage/surestore/cd-writer/.
The 7100/7110 firmware upgrade is available here: http://www.hp.com/isgsupport/cdr/70index.html
IMPORTANT - 7100/7110. The 7100/7110 drew a lot of fire because it shipped with DirectCD (packet-writing software), a CD Copier, and an audio CD creator. It didn't include premastering software for data CDs. Because packet-written CDs can't be read on all operating systems or all CD-ROM drives, the inability to create plain Level 1 ISO-9660 discs was a problem for some users. People who buy this drive should expect to buy additional software. The software bundled with the 7200 was more wisely chosen.
CAVEAT EMPTOR - 4020i. See the notes on the CDD2000 in the previous section. Also, the AdvanSys controller continues to cause problems for some users, which is made worse by HP's refusal to support people who try to use a different card. The best approach seems to be to try the card and stick with it if it works, otherwise buy an Adaptec board (e.g. the 1522A) and use it with that. There may be a newer rev of the AdvanSys board.
A few 4020 users have reported that, after getting lots of "-24 - Target aborted" errors with jarnold's software, they successfully resolved their problems by getting a new drive from HP.
A class-action lawsuit has been filed against HP (for the HP4020i and HP6020i) by the same people who filed the suit against Philips. See the end of section (5-1-4) for links.
RF4100 (2x2/1MB+;SCSI, based on Philips CDD522 but with different firmware)The RF4102 is an RF4100 with more memory.
CDR4220 (4x2/1MB;SCSI, based on the Philips CDD2000)
CDR4240 (4x2/1MB;SCSI, based on the Panasonic CW-7501)
CDR-4400 (4x2/512K;SCSI, based on the Yamaha CDR-100)
CDR480 (8x4/1MB;SCSI, based on the Panasonic CW-7502)
The RF4100 does not support disc-at-once recording.
See http://www.kodak.com/ [ no CD recorder info? ]
PCD200 (?x2/256K;SCSI)The Philips CDD522, Kodak PCD225, and Kodak PCD600 will interface with the Kodak Disc Transporter, which supports unattended duplication of up to 75 CD-Rs, making it a useful combo for CD-R production.
PCD225 (2x2/2MB;SCSI, based on the Philips CDD522)
PCD240 (4x2/1MB;SCSI, based on the Philips CDD2000)
4801 (??;IDE, based on the Mitsumi 4801??)
See http://www.jvc.com/ [no CD-R info? ]
XR-W1001 (1x1/64K;SCSI)The drives are sometimes sold with model numbers that have 2 added, so XR-W2010 might appear as XR-W2012, XR-W2020 as XR-W2022, and XR-W2080 as XR-W2082. The XR-W2626 appears to be an XR-W2020.
[on the JVC web site, no model number?] (12x4/1MB;IDE)
The drives often come bundled with JVC "Personal Archiver" or "RomMaker" software. The XR-W2010 and XR-W2020 also come with "FloppyCD" packet-writing software.
JVC only provides support for drives purchased directly from them, but firmware updates can be found at http://www.jvcinfo.com/service/firmware.htm. If you don't buy a JVC drive from JVC, make sure your vendor provides a warranty.
If you are getting "servo tracking error", "seek error", or "track following error" messages with an XR-W2010 or XR-W2020, your drive may need to be opened up and lubricated. Step-by-step instructions for doing so can be found on http://www.smial.prima.de/old/howtoget.htm. If you're not quite up to that, try turning the drive off and leaving it off until right before you're ready to burn. Some units have trouble when they get warm.
Several users have reported difficulty installing the XR-W2020, but the troubles appear to stem from the SCSI card bundled with the drive rather than the drive itself.
CAVEAT EMPTOR - XR-W2010. Firmware version 1.51 has some serious flaws that can cause problems when using the drive as either a writer or a reader. The v2.05 update fixed most of the problems, but some conflicts with 3rd-party software remained, so the update was withdrawn. Until these problems are fixed, this drive should only be used with the JVC software, and should not be used as a reader. Power-cycling the unit (i.e. powering it off and back on) immediately before a write may cure some problems. For examples and some tests, see http://www.fadden.com/doc/jvc-prob.txt.
While there are a large number of people who are using these drives without problems, one person affiliated with a CD-R software company referred to the XR-W2010 as their "#1 tech support nightmare".
CAVEAT EMPTOR - XR-W2020. The mechanism appears to have the same problems with lubrication as the XR-W2010. After several months of successful use, the unit will start returning "tracking error" messages.
RCD-202 (?x1/64K;SCSI, based on the JVC XR-W1001)The -1000, -5020, and -5040 models are flash ROM upgradeable.
RCD-1000 (2x2/1MB;SCSI, based on the JVC XR-W2001)
RCD-5040 (4x2/1MB;SCSI, based on the JVC XR-W2010)
RCD-4X4 (4x4/1MB;SCSI, based on the Teac CD-R50S)
RCD-1000 units shipped after Sept 1995 can do audio extraction if they have firmware v2.35 or later. An upgrade is available from their BBS.
If you are getting "servo tracking error", "seek error", or "track following error" with a 5040, see the notes in the JVC XR-W2010 section.
CAVEAT EMPTOR - all drives. Pinnacle customer support is reported to be almost nonexistent, except for some recent tech support via e-mail. Many owners of the RCD-5040 are perfectly happy with their drives (see the caveat on the JVC XR-W2010), but most of the stories about Pinnacle's product support are negative.
Pinnacle earned a bad reputation after shipping drives with buggy firmware, a poorly ventilated enclosure, and bad customer support. Some owners of the RCD-1000 have gotten the unit to work, others have given up in despair.
RS-9200CD (?x1/1.2MB;SCSI)The MP-6200 uses a tray, the MP-6201 uses caddies and has a 2MB buffer.
MP-6200 (6x2x2/1MB; 'S' is SCSI, 'A' or 'I' is IDE)
MP-7040 (20x4x4/2MB; 'S' is SCSI, 'A' is IDE)
MP-7060 (24x6x4/2MB; 'S' is SCSI, 'A' is IDE)
MP-8040SE (20x4x4/2MB;PCMCIA-2(SCSI), battery-powered)
MP-9060A (24x6x4/2MB;IDE, reads DVDx4)
MP-9120A (32x12x10/2MB;IDE, reads DVDx8)
MP-9200A (40x20x10/2MB;IDE, reads DVDx12)
The RS1060C does not support disc-at-once recording, reading of digital audio, or subcode-Q data. (One user reported that his RO1060C *could* read digital audio, but the drive took a little convincing. Another user says that it has always been supported, but not documented, so it can be done with the right software, e.g. CDDA v1.5.) The RS-1060C is the RO-1060C in an external case.
The RS-1420C is flash upgradeable (though it can be a little tricky since there are different variants of the drive, and each requires a different ROM image). It does not support packet writing. Most of the commercial versions come with a 2MB buffer (the last digit of the firmware version will be 0, 1, or 2, indicating 512K, 1MB, and 2MB, respectively).
The firmware on the flash-upgradeable MP-6200 should either be at v2.20 or later. Version 1.0 had several problems, version 2.0 didn't get along so well with DirectCD 2.0, and version 2.03 had some DAE issues.
Firmware upgrades are available from Tom Varghese's page listed above (arrakis-ttm.com) and http://www.ricoh.co.jp/cd-r/cgi/e-/version.html.
The MP-6200 "red/green" problem, where the drive starts having trouble accepting media, and sits there flashing red and green, appears to be caused by a buildup of oil on the drive's spindle clamp. See the arrakis-ttm.com site for details.
Some people have found that the MP7040/7060 will start to "stick" after a while, resulting in consistent write errors at roughly the same spot every time. Some people have found that lubricating the drive helps. This is a dangerous procedure, and should not be attempted unless all other possibilities have been exhausted. Details can be found on http://www.don.cohoon.net/ricoh/ricoh.html.
See http://www.pioneerusa.com/cds.html [ mass replication ]
See http://www.pioneer.co.jp/ [ if you can read Japanese ]
DW-S114X (4x4/1MB;SCSI)The PDR-05 is an audio CD-R recorder, described in section (5-12).
Does not support disc-at-once recording. Mainly sold in large jukebox systems.
CDS615E (2x2/1MB;SCSI, based on the Sony CDU920S)The CD-R2 is the CDS615E in an external case. The CD-R2x4 might be the external version of the CDS620E. The CD-R2x6 probably has a name like CDS640E, but it's not listed as such on their web site.
CDS620E (4x2/1MB;SCSI, based on the Sony CDU924S)
CD-R2x6 (6x2/512K;SCSI, based on the Sony CDU926S??)
DisKovery 650 CD-R (2x2/1MB;SCSI, based on the Sony CDU920S)
DisKovery 1300 CD-R (6x2/512K;SCSI, based on the Sony CDU960S?)
Optima CDWriter (6x4x2/2MB;SCSI, based on ??)
CR-2200CS (2x2/4MB;SCSI, based partly on the Philips CDD2000)In all unit designations, 'C' means caddy, and 'T' means tray, 'S' is SCSI, and 'E' is IDE.
CR-2201CS (same as CR-2200CS but with 2x2/1MB)
CR-2401TS (4x2/1MB;SCSI, based on the Philips CDD2000)
CR-4802TE (8x4x2/2MB;IDE) and CR-4802TU (USB)
CR-480ATE (40x32x12/2MB;IDE, sometimes referred to as 48xA)
The devices based on the CDD2000 are flash upgradeable (you should be able to use Philips CDD2000 images).
CAVEAT EMPTOR - CR-2600TE and CR-2801TE. These drives do not support disc-at-once recording. Like the Sony 926 and 928 units, they claim to support track-at-once with nearly imperceptible gaps instead. Ahead's Nero can reportedly do this with the CR-2801TE.
The CR-4801TE with firmware 2.01 and later supports DAO recording. Earlier versions do not. If your recording software doesn't believe that the drive is capable of DAO, you may need to update the software to a version that is aware of the changes in the firmware update.
Later drives, such as the 4802TE, do support DAO.
CDRW8424 (24x8x4;SCSI)[ DynaTek reportedly went out of business. However, the UK site seems
CDM240J (4x2/512K;SCSI, based on the JVC XR-W2010)
CDM400 (4x4/512K;SCSI, based on the Yamaha CDR-100)
CDE260R (6x2x2/1MB;SCSI, based on the Ricoh 6200S)
to be alive and well. ]Older CDM240 units were based on the Yamaha CDR-102. Since the Yamaha CDR-100 is no longer being made, chances are the CDM400 is now a different unit as well.
They also sell the CDM4000, which is a stand-alone CD burner.
PlayWrite 2000 (2x2/1MB;SCSI, based on the Sony CDU920S)
PlayWrite 2040 (4x2/512K+;SCSI)
PlayWrite 4000 (4x4/512K;SCSI, based on the Yamaha CDR-100)
PlayWrite 4001RW (6x4x2/2MB;IDE, based on the Yamaha CDR4001t)
PlayWrite 2060R (6x2x2/1MB;SCSI, based on the Ricoh 6200S)
Model is the Express Writer. There are no apparent model numbers. They used to sell the "old one" (2x2/1MB, based on a Pinnacle (i.e. JVC) drive), more recently they sold the "new one" (4x2/?).
See http://www.micronet.com/HTDOCS/products.html#cdr [ site gone? ]
MasterCD Plus 4x4 (4x4/512K;SCSI, based on the Yamaha CDR-100)
MasterCD Plus 4x6 (6x4/2MB;SCSI, based on the Yamaha CDR-400)
MasterCD Plus 4x12 (12x4/1MB;SCSI, based on the Teac CD-R55S)
PCDR-4X (4x4/512K;SCSI, based on the Yamaha CDR-100)
See http://www.grundig.com/ [mostly in German]
CDR100IPW (4x2/1MB;SCSI, based on the Philips CDD2000)
PX-R24CS (4x2/512K;SCSI, a cousin of the Ricoh 1420C)For all units, 'C' indicates caddy, 'T' indicates tray, 'S' is SCSI, 'A' is ATAPI, 'U' is USB.
PX-W8432T (32x8x4/2MB;IDE), also SCSI PX-W8432Ti/SW with 4MB
PX-W1210TA (32x12x10/2MB;IDE), also SCSI PX-W1210TS with 4MB
PX-W2410TA (40x24x10/4MB;IDE, also 'U' portable USB)
PX-208U (24x8x8/2MB;USB2.0, reads DVDx8, portable)
PX-320A (40x20x10/2MB;IDE, reads DVDx12)
PX-W4824TA (48x48x24/4MB;IDE, TU model is external USB2.0)
All units are flash upgradeable. All units except the PX-R24CS support packet writing.
Users having trouble with the PX-R412C should try turning synchronous transfer off for that drive.
There appears to be an issue with the Plextor PX-320A and a SiS IDE chipset. Using the DMA jumper to change the Plextor drive from UltraDMA to multi-word DMA fixes the problem.
CW-7501 (4x2/1MB;SCSI)Panasonic is part of Matsushita, so the units may also be sold under the Matsushita label.
All units are flash-upgradeable. The CW-7501 should be at 2.0 or greater, and the CW-7502 should be at vX.10 or later (1.10, 3.10, or 4.10 depending on which recorder variant you have; check your current version). Upgrades are available from http://www.acscompro.com/ (click on "Support") [site was down as of May 2002?].
NOTE: there is a known conflict with the Diamond FirePort 40 and the Panasonic CW-7502 CD-R drive. You should upgrade the 7502 firmware to the latest (www.acscompro.com/support/s_cdr.htm), upgrade your FirePort 40 drivers (http://www.diamondmm.com/products/drivers/fireport.html), and add "DisableAutoReqSense=1;do_SCAM=0;" to the FirePort driver (go into the Win95 device settings, select the host adapter, click on Properties, and select the Settings tab).
This problem may affect other NCR/Symbios Logic-based SCSI cards as well. Falling back to the original (1.01) NCR SCSI drivers that come with Win95 should fix the problem.
NOTE: the 7502/7503 units may have a problem with writing near the end of 80-minute discs. The problem is fixed by a firmware upgrade. If you get errors reading data stored near the end of the disc (e.g. errors creating a disc image from a full 80-minute CD or CD-ROM), make sure you have the latest firmware.
CD-R50S (4x4/1MB;SCSI)Apparently the CD-R50S needs to be at firmware 1.0E or later to do quad-speed writing reliably. Power calibration is done via a lookup table rather than adjusted dynamically, so a flash upgrade may be required before some brands of media will work.
CD-W512 (32x12x10/4MB; 'E' is IDE, 'S' is SCSI)
CD-W516 (40x16x10/2MB; 'E' is IDE)
CD-W540E (48x40x12/8MB;IDE, F540 is external USB (6x4x4) or USB2.0)
The CD-R50S and CD-R55S appear to use the same command set as the JVC XR-W2010.
http://www.teac.co.jp/dspd/download/firmware/cd-r55s/updater.html has a nice HTML page about the CD-R55S upgrade.
See http://www.wpinet.com.sg/ [site gone?]
CDR-432 (4x2/1MB;SCSI, based on the Philips CDD2000)The CD-R 622 does not support disc-at-once recording. According to the CDRDAO "readme" file, it is possible to upgrade the 622 (and its Memorex cousin) by writing the D4.0 ROM image for the CRW-1622 to a 27c020 PLCC EPROM and replacing the socketed ROM chip in the drive.
CD-R 622 (6x2/1MB;IDE)
CD-R 632P (6x2/1MB;SCSI, based on the Philips CDD2600)
The CDRW-622 supports packet writing, and is flash upgradeable.
2040R (4x2/512K;SCSI, based on the Ricoh RS-1420C)Many users have had trouble installing the AdvanSys SCSI card that is bundled with this unit. Most of the problems can be corrected by enabling PnP installation, which is disabled by default.
CDR2000 (2x2/512K;SCSI, based on the Ricoh RS1060C)Creative sold several drives with the 32x8x4 rating, starting with the Plextor-based 8432. According to http://www.ping.be/satcp/writer04.htm, the 8433, 8435, 8438, and 8439 are similar but different devices. Looks like they did something similar with the 32x12x10 drive.
CDR2224 (24x2x2/2MB;IDE, based on JVC XR-W2080?)
CDR4210 (4x2/1MB;SCSI, based on the Panasonic CW-7501)
CDR4224 (24x4x2/2MB;IDE, based on a JVC XR-W4080)
CDR?? "CD Studio" (24x4x4/2MB;IDE, based on ??)
CDR6424 (24x6x4/2MB;IDE, based on Ricoh 7060A)
CDR8432 (32x8x4/2MB;IDE, based on PX-W8432T; also 8433/8435/8438/8439)
CDR8433 (same as 8432, based on Panasonic CW-7585)
CDR8435 (same as 8432, based on Samsung SW-208)
CDR8438 (same as 8432, based on Samsung ??)
CDR8439 (same as 8432, based on Panasonic CW-7586)
CDR121032 #1 (32x12x10/2MB;SCSI, based on Plextor PX-W1210)
CDR121032 #2 (32x12x10/2MB;SCSI, based on Lite-On LTR-1210)
CDR161040 (40x16x10/2MB;IDE, based on ??)
CDR241040 (40x24x10/2MB;USB or FireWire, based on ??)
Generally speaking, reading the retail box won't tell you what's inside.
CR-622 (6x2/1MB;IDE, based on the Wearnes CD-R 622)
CRW-1622 (6x2x2/1MB;IDE, based on the Wearnes CDRW-622)
CRW-2642 (6x4x2/2MB;IDE, based on the Yamaha CRW-4260??)
CDRW-2216 (16x2x2/1MB;IDE, based on the Yamaha CRW-2216E)
CDRW-2224 (24x2x2/2MB;IDE, based on JVC XR-W2080?)
CDRW-4206-USB (6x4x2/2MB;USB, based on ??)
CRW-4224 (24x4x2/2MB;IDE, based on JVC XR-W4080?)
CDRW-8220 (20x8x2/2MB;SCSI, based on ??)
CDRW-12432 (32x12x4/2MB;IDE, based on ??)
"32X CD ReWritable Drive" (40x32x12/?MB;IDE)
"40X CD ReWritable Drive" (48x40x12/2MB;IDE)
"48X CD ReWritable Drive" (48x48x12/2MB;IDE)
"48Xv2 CD ReWritable Drive" (48x48x24/2MB;IDE)
"52X CD-ReWritable Drive" (52x52x24/?MB;IDE)
Hi-Val doesn't build CD recorders. They repackage and provide support for recorders built by others. The actual model you get will vary (Wearnes, Ricoh, Philips, JVC, Mitsumi, and others have been reported).
CR-622 (6x2/1MB;IDE, based on the Wearnes CD-R 622)The CRW-1622 often came bundled with NTI's software, but the version included didn't work correctly. Upgrading to a more recent version of the software (http://www.ntius.com/) resolved the problems.
CRW-1420C (6x2/512K;SCSI, based on the Ricoh 1420C??)
CRW-1622 (6x2x2/1MB;IDE, based on the Wearnes CDRW-622)
CDRW-2216 (16x2x2/1MB;IDE, based on the Yamaha CRW-2216E)
See http://www.traxdata.com/ [ site now "under construction" ]
CDR4120 (12x4/1MB;SCSI, based on the Teac CD-R55S)The CDRW2260 "Pro" may also use a Philips CDD3600?
CDRW2260 "Pro" (6x2x2/1MB;SCSI, based on the Yamaha CRW-2260)
CDRW2260 "Plus" (6x2x2/1MB;IDE, based on the Philips CDD3610?)
CDRW-4260 "Pro" (6x4x2/2MB;SCSI, based on the Yamaha CRW-4260)
CDRW-2224 "Plus" (24x2x2/?MB;???, based on Philips CDD3801?)
CDRW-4424 "Plus" (24x4x4/2MB;IDE, based on the Philips CDD4201?)
CDW6206A (6x2x2/512K;IDE)A user who was getting nothing but power calibration complaints with the CRW1032A and firmware 7.EZ found a laser power adjustment tool in the 7.GZ update from the www.acercm.com site. The North American version reportedly doesn't come with the tool, but it may not be needed.
WT4046 (6x4x2/2MB; "EI" model is IDE)
WT2036 (6x2x2/1MB; "EI" model is IDE)
WT2082 (20x2x2/4MB;SCSI, "EXT" is external, based on ??)
WT2444EI (24x4x4/2MB;IDE, based on the Philips CDD4201?)
WT3244EI (32x4x4/2MB;IDE, based on ??)
WT3284EI (32x8x4/4MB;IDE, based on Plextor PX-W3284?)
"Raptor" (32x12x10/4MB; "Red" is IDE; based on Sanyo CRD-BP1300P??)
"X-File" (32x12x10/2MB;IDE, reads DVDx8, writes DVD+RWx2.5)
"T-Rex" (40x16x10/2MB;IDE, based on Sanyo CRD-BP1400P??)
"SfinX 16" (40x16x10/8MB;IDE, also reads DVDx10)
"Storm 24" (40x24x10/?MB;IDE)
"Storm 32" (40x32x10/4MB;IDE)
"Frisby II" (40x40x12/2MB;USB2.0, portable)
"Storm 40" (48x40x12/4MB;IDE)
"Storm 48" (48x48x16/2MB;IDE)
BCE62IE (6x2x2/1MB;IDE, based on the Philips CDD3610??)The BCE62IPE is the BCE62IE with a parallel-port IDE converter.
See http://www.sanyo.com/ [ no CD-R info? ]
CRD-R800S (20x8/2MB;SCSI)Firmware v1.10 or later is highly recommended for the CRD-R800S. For some reason, the firmware update was only available on the "BURN-Proof" web site at http://www.sannet.ne.jp/BURN-Proof/. [ It doesn't seem to be there anymore. ]
CRD-BP4 (40x16x10/2MB;SCSI, also in 4MB)
CRD-BP1400P (40x16x10/2MB;IDE, also in 4MB)
CRD-BP1500P (40x24x10/2MB;IDE; 'U' is USB)
CRD-SBP15A (32x24x10/2MB;IDE, portable, for OEM only)
CRD-BP1500U40X (40x40x12/4MB;IDE, external is USB2.0)
It looks like Mirai Technologies (http://www.mirai-technologies.com/) resells these drives.
190100 (6x2x2/1MB;Parallel, based on the Ricoh MP-6200)All products are standard recorders combined with Micro Solution's parallel-port interface.
190120/190126 (6x4x2/?MB;Parallel, based on the Yamaha CRW-4261)
190127 (8x4x2/2MB;Parallel, based on the Mitsumi CD-4802TE)
224ei (24x2x2/2MB;IDE, based on the JVC XR-W2080)
226ei (6x2x2/1MB;IDE, based on the Philips CDD3610??)
428ei (8x4x2/2MB;IDE, based on the Mitsumi CR-4802TE)
428USB (8x4x2/2MB;USB, based on the Mitsumi CR-4802TU)
416si (16x4x4/2MB;SCSI, based on Yamaha CRW-4416S?)
448USB (8x4x4/2MB;USB, based on ??)
8824si (24x8x8/4MB;SCSI, based on Yamaha CRW-8824??)
8832ei (32x8x8/2MB;IDE, based on ??)
121032ei (32x12x10/2MB;IDE, based on Lite-On 32x12x10)
161040ei (40x16x10/8MB;IDE, based on CRW-2100?)
241040ei (40x24x10/2MB;IDE, also as USB)
Xtreme32 #1 (40x32x10/2MB;USB2.0 and USB (8x4x4))
Xtreme32 #2 (48x32x12/2MB;USB2.0 and USB (8x4x4))
Mach40 #1 (48x40x12/2MB;IDE)
Mach40 #2 (48x40x16/2MB;IDE)
Xtreme48 (48x48x12/2MB;USB2.0 and USB (8x4x4))
ZipCD (24x4x4/2MB;IDE, based on the Philips CDD4201)
ZipCD external (6x4x4/2MB;USB, based on ??)
CD-RW Predator 8x4x32 FireWire (32x8x4/2MB;FireWire)
ZipCD 12/10/32 (32x12x10/2MB;IDE, based on Plextor PX-W1210T)
ZipCD 16/10/40 (40x16x10/2MB;IDE, based on ??)
CD-RW 24x10x40 USB (40x24x10/2MB;USB)
CD-RW 40x12x48 USB (48x40x12/2MB;USB2.0), also available as FireWire
CD-RW 48x24x48 USB (48x48x24/2MB;USB2.0)
CD-RW 52x24x52 USB (52x52x24/2MB;USB2.0)
CED-8041B (24x4x2/2MB;IDE)The first two *might* be based on the Sony 100/120 models. There are indications that, at the very least, the firmware is different (the Goldstar units reportedly can "overburn" discs, while the mentioned Sony units couldn't when these were released.)
GCC-4120B (32x12x8/2MB;IDE, reads DVDx8)
GCC-4320B (40x32x10/2MB;IDE, reads DVDx16)
CR1420C (4x2/512K;SCSI, based on the Ricoh RS-1420C?)
CRW620 (6x2/1MB;SCSI, based on ??)
CRW622 (6x2/1MB;IDE, based on Wearnes CD-R 622??)
CRS446U (6x4x4/1MB;USB, "crab shell")
CRW9420 (20x4x4/2MB;IDE, based on Ricoh MP-7040A?)
CRW9624 (24x6x4/2MB;IDE, based on Ricoh MP-7060A?)
DRW4624 (24x6x4/2MB;IDE, reads DVDx4)
RW5120A (32x12x10/2MB;IDE, reads DVDx2.4)
DVRW2412PRO (32x12x10/2MB, also reads DVD+RW)
CRW3248 (48x32x12/2MB;IDE, has an option for 8MB buffer)
SD-R1002 (24x4x4/2MB;IDE, reads DVDx4)
8/4/32 veloCD (32x8x4/4MB;IDE, based on ??)
12/10/32 veloCD (32x12x10/2MB;IDE, based on Plextor PX-W1210TA)
16/10/40 veloCD (40x16x10/2MB;IDE, based on Sanyo CRD-BP1400P?)
24/10/40 veloCD (40x24x10/2MB;IDE, also external USB2.0 and FireWire)
32/10/40 veloCD (40x32x10/2MB;IDE, based on Sanyo CRD-BP1600PN?)
40/12/48 veloCD (48x40x12/2MB;IDE)
48/16/48 veloCD (48x48x16/2MB;IDE, also external USB2.0)
LTR-0841 (32x8x4/2MB;IDE)Some of the drives appear to be based on Plextor units. It has been claimed that the LTR-0841 can be upgraded to an LTR-12101B with a firmware upgrade; see http://www.cdrinfo.com/Sections/Tips/oc_Lite-On.asp.
LTR-48125S (48x48x12/2MB;IDE, same as 48125W/48126S?)
Customer support issues are deferred to the dealer.
There is an internal configuration program called "WSES" that can be used for testing drives and discs. Copies can be found on the web.
CDI CD00000 (20x4x4/2MB;SCSI)All models are recorders built by major manufacturers, repackaged and supported by CenDyne. In many cases the model numbers refer to slight changes in packaging (e.g. Windows vs Mac) or internal vs external variations of the same drive.
CDI CD00001 (20x4x4/2MB;SCSI)
CDI CD00015 (20x4x4/2MB;SCSI)
CDI CD00016 (24x4x2/2MB;IDE)
CDI CD00017 (24x4x4/2MB;IDE)
CDI CD00018 (32x4x4/2MB;IDE)
CDI CD00023 (32x8x4/2MB;IDE)
CDI CD00028 (32x12x4/4MB;SCSI)
CDI CD00029 (24x6x4/2MB;SCSI)
CDI CD00030 (24x6x4/2MB;SCSI)
CDI CD00032 (24x6x4/2MB;SCSI)
CDI CD00036 (20x8/2MB;SCSI)
CDI CD00037 (20x8/2MB;SCSI)
CDI CD00038 (20x8/2MB;SCSI)
CDI CD00039 (20x8/2MB;SCSI)
CDI CD00040 (24x6x4/2MB;SCSI)
CDI CD00045 (32x12x4/4MB;SCSI)
CDI CD00047 (32x6x4/2MB;IDE)
CDI CD00055 (32x12x10/4MB;IDE)
CDI CD00056 (24x4x4/2MB;IDE)
CDI CD00057 (32x8x8/2MB;IDE)
CDI CD00059 (32x12x10/2MB;IDE, reads DVDx8)
CDI CD00063 (32x12x10/?MB;Firewire)
CDI CD00068 (20x4x4/?MB;PCMCIA)
CDI CD00086 (20x4x4/?MB;USB)
CDI CD00087 (40x16x10/?MB;IDE)
CDI CD00090 (40x20x10/2MB;IDE)
CDI CD00091 (40x24x10/2MB;IDE)
CDI CD00092 (20x4x4/2MB;PCMCIA or USB)
CDI CD00094 (40x24x10/2MB;FireWire)
CDI CD00102 (32x12x10/2MB;USB2.0)
CDI CD00103 (40x16x10/2MB;USB2.0)
CDI CD00104 (40x24x10/2MB;USB2.0)
CDI CD00107 (40x32x12/2MB;IDE)
CDI CD00116 (24x8x8/2MB;USB2.0)
CDI CD00117 (48x40x12/2MB;IDE)
CDI CD00118 (48x48x12/?MB;IDE)
CDI CD00122 (48x40x12/2MB;IDE)
CDI CD00123 (40x16x10/2MB;IDE, read DVDx12)
CDI CD00134 (40x40x12/2MB;USB2.0, top-loading)
CDI CD00137 (48x48x12/?MB;IDE)
CDI CD00154 (40x32x12/2MB;USB2.0)
CDI CD00167 (40x32x10/2MB;IDE, read DVDx12)
CDI CD00172 (48x40x12/2MB;USB2.0)
CenDyne has the distinction of using the least imaginative naming scheme of any distributor (the polar opposite of Waitec).
VST Portable CD-R/RW (20x4x4/2MB;FireWire;portable)
CRW-4012A (48x40x12/2MB;IDE, "-U" model is external USB2.0)
SN-308B (24x8x8/2MB;IDE, read DVDx8)
SM-308B (32x8x4/2MB;IDE, read DVDx8)
SM-316B (40x16x10/8MB;IDE, read DVDx12)
SM-332B (40x32x10/8MB;IDE, read DVDx12)
SM-348B (48x48x24/8MB;IDE, read DVDx16)
APS "52x24x52 FireWire & USB CD-RW" (52x52x24/?MB;FireWire & USB2.0)Products are repackaged drives from other manufacturers.
The MTBF (Mean Time Between Failures) on these drives is typically 50,000 to 100,000 hours, and they come with a 1 year warranty. Compare that to hard drives rated at between 500,000 and 1,000,000 hours with a 3 or 5 year warranty and that should give you some idea.
Most of the drives available today weren't meant for mass production of CD-Rs. The only exceptions are the venerable Philips CDD 522, Kodak PCD 600, and Sony CDW-900E.
Incidentally, MTBF is not an estimate of how long the drive will last. Rather, it's an estimate of the failure rate of the drives during the expected lifetime of the device. Once you exceed the expected lifetime, which is often on the order of a couple of years, the anticipated failure rate increases. If you have new drives with an MTBF of 25,000 hours, and you run 1000 units for 100 hours, you can expect to see four of them fail. It does NOT mean you can expect them to run for 2.8 years and then all fail at once.
If you're about to buy a computer system and are seriously thinking about buying a CD-R, here are some things to keep in mind. (See the next section if you're interested in Mac hardware instead of an IBM PC.)
CPU: buy a mid-range Pentium-class machine or better. In general it's a good idea to buy a fast machine, since systems tend to be outdated after a year and obsolete after three or four. A '486 is a *minimum* configuration for a CD-R system; a Pentium gives you some breathing room. Pentium II and above is more power than you need, but that's not necessarily a bad thing.
Motherboard: for SCSI, anything with PCI slots is fine. For IDE, anything above UDMA/33 is overkill. See section (5-15) for configuration notes and a warning about certain bus-mastering drivers.
SCSI: the SCSI interface remains a popular choice for CD recorders and CD-ROM drives, though improvements like UDMA/133 are changing the way people build high-end computers. Whether it's built into the motherboard or on a separate card, make sure the host adapter supports ASPI and ASPI for Windows (see section (5-7)). Wide Ultra-SCSI is useful if you're buying a fast hard drive, but CD recorders don't move data fast enough to require it. Bus-mastering SCSI cards are preferred over non-bus-mastering cards, because they can move data to and from system memory directly, without the CPU's involvement, making things faster.
Parallel: some vendors are selling parallel-port CD-R drives. You should have an EPP-enabled parallel port (if you have a Pentium or later, chances are you have one).
Sound: the Creative Labs SB16 and AWE32 boards are widely supported and very popular, but if you're thinking seriously about recording sound through it, you'll want to consider alternatives. See sections (3-12) and (3-13) for other options.
Hard drive: needs to be reasonably fast, and large enough to hold whatever data you plan to put on a CD. IDE hard drives work fine. See section (5-6) for more details.
Video card and monitor: depends on what you want to do. A PCI-based video card is practically a requirement these days, and 17" monitors are inexpensive now. If you're planning on creating multimedia products, scale up.
CD-ROM: SCSI and IDE both work, but some drives work better than others. See section (5-5).
Any Mac of Quadra 700 or higher capability with a reasonably fast disk should be suitable for 2x writing. All PowerMac-class machines, and probably most Mac clones, should work fine at high speeds. PowerBook users should proceed with caution on machines earlier than the 3400 and G3 models.
Any of the SCSI or (for appropriately equipped machines) USB and FireWire recorders should work. Verify with the vendor of the software you plan to use that the drive you have in mind is supported. You may be able to use the internal IDE connector on some Macintoshes as well.
Using the "simulated cut" feature available on Toast and other software is also prudent, at least until you get a feel for the system. Make sure you turn off file sharing before you start a burn, or things will fail if it tries to read a file that's already open. You may also have trouble writing from the boot/system volume, since it will always have files open.
The good news for Mac owners is that the hardware and software configuration for CD-R usually goes rather smoothly.
Besides the obvious question - can it read CD-R discs that you create - there's also the question of how well the drive works as the source device when copying discs. To be more specific:
You can see speed and quality test results on http://come.to/cdspeed.
Older NEC models tend to hog the SCSI bus. Older NEC, Mitsumi, and Acer models (e.g. NEC 3x and Acer 8x) may have trouble reading CD-Rs.
There is one hard and fast rule for direct CD-to-CD duplication: the source drive must be faster than the target drive (e.g. source 4x if target is 2x, source 6x if target is 4x).
A quick summary of features for several models can be found at: http://www.fwb.com/ts/cdt/cdt_support.html
Any recent hard drive will work fine. Back in 1998 this was the subject of some concern, but modern drives are much faster and more intelligent.
There is a fair amount of confusion over what exactly is an "AV drive". A brief discussion is presented here; for more information see Bertel Schmitt's article at http://www.fadden.com/doc/avdrive.txt.
The most important issue is thermal recalibration. Older hard drives would pause for up to half a second (or even up to a full second, depending on who you believe) every so often to adjust the head positioning to the current operating temperature. For most applications this goes unnoticed, but when recording a CD-R you must write the current track to completion without interruption. "AV" drives deal with the problem in a way that doesn't disrupt the disk activity.
A drive that does a quick thermal recalibration is acceptable if the system is otherwise fast enough or the buffer in the CD-R unit or in the recording software is large enough (early drives had only 64KB, while current drives have 2MB or 4MB, making it much less of an issue). You need to be sure that the recorder's write buffer won't empty during the recal period, or you'll end up with a buffer underrun.
Most modern hard drives do smart thermal recalibration. This really isn't something you need to worry about anymore.
What separated a Seagate Barracuda from a Seagate Barracuda AV is that the latter is tuned for AV performance. This was simply a software change that affected cache allocation algorithms, error correction, and other SCSI parameters to get better performance for transfers of large blocks of contiguous data. These sorts of optimizations were very important for digital video running at a few MB/sec, back when that was close to the maximum capability of the drives.
If you think AV optimizations will help you, you should take a look at "Dr. SCSI" at http://www.scsitools.com/.
Some systems have SCSI built in, some don't. This section is intended for PC users who want to add SCSI devices. Owners of SCSI-less Macintoshes should use an interface recommended by Apple.
Using different SCSI adapters for the HD and the CD recorder used to be recommended, but should not be necessary with non-ISA adapters. If your recorder hogs the SCSI bus, though, the HD may not be able to keep the write buffer full. Under some operating systems, particularly OS/2, devices that support SCSI disconnect will work better than those that don't.
In general, the faster the better. PCI or the (now uncommon) VLB is better than ISA, and the board should support (and have enabled) SCSI disconnect. It is not necessary to use Wide or Ultra SCSI for a CD recorder; the speed requirements for all existing recorders are easily met by "narrow" Fast SCSI. If you think you may be buying a speedy SCSI hard drive or other device in the near future, though, you may want to buy a card that supports faster protocols.
You should enable synchronous transfers for devices that support it. Most CD recorders should. If the device doesn't work with it on, turn it off and try again.
The adapter MUST support the ASPI standard (ASPI provides an interface between software and the SCSI controller) for both DOS and Windows.
If you want to boot from a CD-ROM on a SCSI drive, make sure the SCSI card supports booting from removable media.
For some tips on cabling and termination, see Bertel Schmitt's article at http://www.fadden.com/doc/scsi-trm.txt.
The next few sections detail the more popular SCSI cards. There are many others, e.g:
Advansys - http://www.advansys.com/
DTC - http://www.datatechnology.com/
CSC - http://www.corpsys.com/
These are all ISA controllers, good for putting a CD recorder on, not so good for putting a hard drive or fast CD-ROM drive on. If you have an IDE-based system and just want a SCSI card for driving your CD recorder and maybe a scanner or tape drive, any of these (as well as any of the variations of these) will work fine.
The Adaptec 2940 (PCI) is a popular choice -- if not *the* most popular choice -- though some users have reported problems with the Adaptec 2840 (VLB). See the README that comes with Adaptec EZ-SCSI v4.0 and later for some important performance tests you can do with SCSIBench. The 2930 is also a good choice for CD recording.
If you're having trouble writing CD-Rs with the 2940UW, go into the configuration menu (hit Ctrl-A while booting) and make sure the drive is set for 10MB/sec with Wide Negotiation disabled.
A few notes on the 2910, 2920, 2930, and 2940 cards:
The 2940U2W has four connectors (internal 68pin Ultra2-LVD, internal 68pin Ultra2, internal 50-pin, external 68-pin Ultra2) and comes with a special 50-pin cable that ends in a 50-pin (HD) external plate. So you can have both 50-pin and 68-pin external connectors, as well as 50-pin and 68-pin internal connectors. On previous cards, you could only use two connectors at a time, but on this card you can use all five at once.
The ASUS SC-200 is one example of a Symbios Logic 810-based card (in this case, the NCR 53C810). Such cards offer solid performance at a reasonable price, and may be a better choice than the Adaptec cards for many users. (Be sure to examine these types of cards closely though: the least expensive among them are only meant to work with a motherboard BIOS that supports SCSI. This could cause trouble on other motherboards if you wanted to boot from a SCSI hard drive.)
The ASUS SC-875, based on the 53C875 chip, offers Wide SCSI connectors as well.
Symbios Logic is currently owned by LSI Logic. For product information, see http://www.lsilogic.com/products/io_standard/index.html.
Inexpensive SCSI cards based on the LSI Logic SYM53C875 chip. The DC-390U supports Ultra SCSI, while the DC-390F supports Wide Ultra SCSI.
The "SlimSCSI" 1460 and 1480 are PCMCIA SCSI adapters for use in laptops and other portable devices. The 1460 requires a PC card slot and supports SCSI-2, while the 1480 requires a CardBus slot and supports UltraSCSI devices.
The "MiniSCSI" 1350 allows you to connect SCSI devices to your parallel port. If you use this you will be limited to parallel-port speeds, so you may not be able to record at more than 2x.
You can, though there may be reasons not to. The seek times tend to be slower than a standard CD-ROM drive because the head assembly is heavier. Early CD recorders were optimized for writing, which doesn't require fast seeks, and some users experienced jerky video playback as a result. Most current models have pretty good seek times though (about 100ms vs. 80ms for a playback-only drive).
The MTBF on CD-R units has historically been lower than that of CD-ROM drives, so it may be wise to use a different drive for general use to preserve the life of the CD-R. Now that CD recorders are cheap enough to be nearly disposable, though, there's not much point in worrying about them. See also section (5-27) on laser diode lifetime.
(What follows are instructions for getting some of the early consumer CD recorders to work as CD-ROM drives. You shouldn't need to worry about any of this unless you bought an old drive in an auction.)
If you're using Win95, some older CD recorders don't show up as readers without additional drivers, or (for SCSI drives) show up as 8 separate LUNs. (LUNs are Logical UNits, useful for distinguishing between different items loaded in a CD jukebox.) The reason why some older recorders don't show up by default is that they're classified as "type 4" SCSI-2 devices, which is used to indicate write-once devices. Standard CD-ROM drives are "type 5".
HP and Philips used to supply drivers for their older units, and Corel used to supply several drivers for with their CD Creator product. You used to be able to get get a patch from Adaptec at ftp://ftp.adaptec.com/pub/BBS/win95/cdr4up.exe that would allow many type 4 drives, including the Yamaha CDR-100/102 and JVC XR-W2010, to appear as CD-ROM drives, but it appears to be gone. You may be able to find these archived on the web.
If you don't have the drivers, you can still old SCSI drives to work under Win9X by loading the real-mode drivers like this (example is for an Adaptec 2940):
DEVICEHIGH=C:\SCSI\ASPI8DOS.SYS /DIn Autoexec.bat:
LH C:\WINDOWS\COMMAND\MSCDEX.EXE /D:ASPICD0 /M:12Incidentally, to *remove* the Adaptec cdr4up driver, you should remove the file "CDR4VSD.VXD" from \Windows\System\Iosubsys, and reboot.
For IDE recorders, you need a more specific driver. The manufacturer's web page likely has a link. See also http://www.drivershq.com/ and http://www.windrivers.com/.
This is a general CD-ROM question rather than a CD-R question, but since some of the newer recorders are available in either configuration it seems worthwhile to address it here.
The advantage of a tray is convenience. If you want to put a CD in the drive, you can just drop it in, instead of buying a pile of caddies and hunting for a free one.
The advantage of a caddy is durability. CDs are less likely to be scratched if they're put into a caddy and left there (VERY important if you have children), and the internal mechanism is less likely to collect dust. The tray units usually have a worse MTBF rating, because they have more moving parts.
There have been reports that, at 12x and higher, some CDs will cause loud vibrations in tray models, but work fine in caddy models. Not everyone has had this problem though.
It used to be the case that you had to get a caddy drive if you wanted to mount it sideways, but many tray models have tabs that will hold the CD in place. Having to use the tabs does reduce the convenience normally offered by a tray model though.
Which you should choose depends on your needs and circumstances. If you are planning to write to a disc several times (multisession, packet writing, or anything with CD-RW), you are better off with the disc in a caddy.
With a little extra care, yes. For a Jaz drive, defragmenting the drive right before starting a burn seems to be the key to success. It's also very important to ensure that nothing else is trying to access the drive while the write is underway.
One user reported being able to write at 1x from a DDS tape drive using Seagate's Direct Tape Access, but this isn't recommended. Copying the data to a hard drive and doing the burn from there is much more likely to succeed.
There are no known instances of successful CD-R burns using punched card readers as the source device.
Doing a test run is strongly recommended when using any of these devices.
OPC stands for Optimum Power Control. Most CD-R units do a power calibration test before writing to adjust the laser power to the correct strength. Different brands of media and different recording speeds require slightly different power levels. Too much power can create oversized marks which can interfere with each other, and too little power can produce undersized marks which, in extreme instances, can cause read failures.
The recorder reads a recommendation for the initial power level from the Recommended Optimum Recording Power value from the ATIP (section (2-38)) on the disc. This is used as a starting point for a series of write tests in the Power Calibration Area (PCA) of the disc.
Running OPC goes a step farther by actively monitoring the write process and adjusting the laser power as needed. If the writer encounters dust or fingerprints, the laser power can be increased to burn through the obstacles. This is especially useful for discs that are moved around between recording sessions, such as CD-RW discs or multisession CD-Rs.
For more information, see the OSTA white paper on the subject at http://www.media-r-us.com/technology/pdf_files/running_opc.pdf (it used to be on the www.osta.org web site, but doesn't seem to be there anymore).
Audio CD-R/CD-RW recorders are similar to computer CD-Rs, except that they're intended to be part of a recording system rather than attached to a Mac or PC. They have audio inputs and front-panel controls like you'd find on a tape deck. They are usually more expensive than CD-Rs meant for computers. Some CD-Rs have both audio and SCSI-II interfaces.
There are two classes of audio CD-R, consumer and professional. The units targeted at consumers require special audio blanks, and employ SCMS (Serial Copy Management System, section (2-25)) to prevent making copies from a copy. The audio blanks used to be 4x to 5x the cost of computer CD-R blanks and only held 60 minutes of audio, but 74-minute "Consumer Audio" blanks are now available for moderately more than regular CD-R blanks.
The "professional" units use regular CD-R blanks and don't obey SCMS, and generally have a wider set of features and input/output connectors.
If you already have a computer, it's probably cheaper to buy a computer CD-R and a good sound card or digital transfer card (see sections (3-12) and (3-13) for more info). The ability to edit the sound on a computer before writing a CD can be very useful. However, there are some advantages to using an audio CD-R (not all features are present on all models):
You can't copy data CD-ROMs with an audio-only recorder.
(Incidentally, the difference in price for the audio CD-R blanks is due to licensing agreements and volume. The manufacturer pays a royalty to a studio consortium under the assumption that everything recorded to an audio CD-R is pirated material. The technology is identical; the "audio" discs just have a mark that says a royalty has been paid. See also section (7-17).)
It is theoretically possible to convince a "consumer" audio CD recorder to accept regular blanks, but in practice this requires modifying the hardware. Some dealers will sell modified units, with altered firmware or additional circuitry, for a higher price (and perhaps a separate warranty). With the Philips 870/880 units manufactured prior to November 1998, it's possible to trick the recorder by manually ejecting and replacing the disc right before recording. Some of the "code free DVD" sites also sell CD-R chips, e.g. http://www.dvdupgrades.ch/. See also section (7-18).
(And now for some increasingly outdated examples...)
Examples of "consumer" audio CD-R units are the Pioneer PDR-04 and PDR-05 (http://www.pioneerelectronics.com/).
Marantz makes professional-grade CD-R units, e.g. the CDR615 and CDR620.
Philips sells the CDR870 and CDR880 (based on the CDD3600), which support both CD-R and CD-RW media. http://www.acdr.philips.com/products.htm. If you're interested in the Philips CDR765, a consumer-grade dual CD deck, see a detailed article at http://www.gallagher.com/music/cdr.htm and some notes at http://members.tripod.com/~charleswolff/cdr765.html.
HHB sells a "professional" unit, the CDR880. http://www.hhb.co.uk/.
There are many other models and vendors -- Denon, Harmon Kardon, others. Shop around.
In computer terms, hardware is the stuff you can hit with a baseball bat, and software is the stuff you can only swear at. Firmware is software that lives on your hardware. In more concrete terms, the firmware on your CD recorder is what controls the operation of the device, and handles everything from decoding CD-ROM sectors to writing the disc table of contents.
Sometimes there are bugs or missing features that are added by updates. Firmware upgrades have been used to add features like disc-at-once recording and fix bugs like reversed left and right audio channels. Sometimes the upgrade will inadvertently add bugs, causing the recorder to work improperly.
Firmware can be stored in an umodifiable form, such as a ROM chip, or in a rewritable form, such as "flash" ROM. In the former case, firmware upgrades are accomplished by physically removing a chip from inside the device, and replacing it with a new one. Devices with "flashable" firmware, on the other hand, can be upgraded by downloading a new set of firmware over the Internet.
You have to be careful when upgrading the firmware on a drive yourself. If it requires physical replacement, you run the risk of breaking pins off of the chip. Flash upgrades won't result in physical damage, but in some cases a failed upgrade can render the device unusable. Always follow the instructions exactly, and NEVER do an upgrade with anything that didn't come from the manufacturer or a trusted source.
Suppose you want to upgrade your recorder. The first step is to remember famous words of wisdom: if it ain't broke, don't fix it!
The second step is to figure out if your firmware is upgradeable. The manual should tell you. Most drives are, but some exceptions are noted for specific drives in the subsections under (5-1).
The third step is to determine what version of firmware you currently have. Some SCSI cards on PC or UNIX systems will display a list of attached devices when the system boots. There's usually a column with a version number in it.
On a PC running Win95, go into the Device Manager (either from the Control Panels or by asking for Properties on My Computer), and find the CD-ROM drives in the device tree. Select the CD-R drive, hit the "Properties" button, and then click on the "Settings" Tab of the window that opens. Look for "Firmware Revision".
Mac users with Toast can hit Command-R to display the information. If your software doesn't have such a feature, you will need to run SCSI Tools to check the identification string.
The fourth step is to find the upgrade file. Usually the manufacturer's web site will have them. If not, sometimes you can find a repository on the web. (There was a nice one on http://www.ahead.de/en/firmware.htm, but that appears to be gone now.)
The fifth step is to apply the upgrade. This can be trivial or fairly challenging, depending on the device. Be sure to read the instructions *carefully* before applying the upgrade -- if it fails, the recorder could be rendered inoperable.
Section (5-24) discusses the somewhat dangerous practice of flashing a drive with firmware intended for a different drive.
By all accounts, they work just fine. Most such drives are IDE devices with a converter (e.g. an enclosure with a parallel-to-IDE converter).
Parallel-port drives require an ECP/EPP parallel port, which most (all?) machines have. Some BIOSs allow you to switch between ECP/EPP and "standard" mode; if you're having trouble, be sure it's set correctly.
Some people who have bought off-the-shelf parallel-to-IDE converters have found that writing at 4x doesn't work very well. This may account for why all drives that ship with parallel port support are 2x writers.
USB recorders work fine at 4x when connected directly to the computer. You may need to reduce speed to 2x if you use a hub. Some people have reported that their Windows systems were crashing until they turned auto-insert notification off (see section (4-1-1)). Windows users should be running Win98 or later -- Win95b may or may not work. Be warned that some USB SmartMedia readers install drivers that interfere with the ASPI layer; if you have problems with one, uninstall the drivers for the device and run ASPICHK.
You need USB 2.0 to take advantage of drives faster than 6x4x4. Support for USB 2.0 has been spotty, but as of mid-2002 it's becoming more common on new motherboards and software support is improving.
A PC user with USB 2.0 ports discovered that their recorder would only work successfully under WinXP or Win2K. Older versions of Windows wouldn't work.
If you're having problems when disconnecting a device from the USB hub, see http://support.microsoft.com/support/kb/articles/Q253/6/97.ASP.
IEEE 1394 (FireWire/i.Link) devices should only be used with recent versions of Windows on PCs (e.g. Win98SE or Win2K, not Win95, Win98, or WinNT). Linux support for 1394 was still listed as "experimental" in early 2002.
Some personal notes on FireWire:
I bought a Western Digital PCI 1394 card, an ADS Technologies Pyro 1394 Drive Kit, and an HP DVD100i CD/DVD+RW recorder with an IDE interface. As an experiment, I put the HP recorder into the ADS case, and plugged it in.
Under Windows 98SE, I was able to use the drive as a CD-ROM reader and DVD video player. The HP software got a little confused during installation, claiming that it couldn't find the drive, but when asked to record a CD it was able to find the device. However, neither the HP RecordNow software nor Nero was able to successfully record an audio CD. The drive just stopped working a few minutes in.
When the drive was subsequently connected to the IDE bus, it worked fine. Subsequent experiments showed that the problem appears to be some sort of incompatibility with the motherboard -- my VIA-based Soyo K7V Dragon+ seems to be incompatible with 1394 devices. I haven't tried the experiment, but my guess is that the recorder would've worked just fine in the ADS case on a compatible system.
For the curious, http://www.fadden.com/techmisc/my-pcs.htm#1394 has the gory details on what I went through.
(This section assumes you're using a PC.)
You generally want the hard drives and CD-ROM drives on different channels, or CD-ROM accesses can interfere with hard drive accesses. Most older devices can't share the ATA bus, so only one device can be active at a time.
For example, suppose you have a hard drive as master and a CD recorder as slave on the same channel. If you issue a command to write some blocks to the CD recorder, the system can't read anything from the hard drive until the CD write request completes. As long as the system is fast enough, and can read enough data between writes to keep the CD recorder's buffer full, this doesn't create any problems.
If you put the hard drive and the CD recorder on different channels, the commands are allowed to overlap. In practice, on Win9x systems this doesn't make much of a difference, because Win9x won't usually access more than one IDE device at a time. On systems like OS/2 and Linux, the difference is more significant.
Proposals for command overlap (sending commands to multiple devices simultaneously) and command queueing (sending several commands to the same device all at once) were introduced as optional features during the development of the ATA-3 specification. They're part of ATA/ATAPI 4. For command overlap to be effective, both devices on the channel must support the feature. If the hard drive does but the CD recorder doesn't, you won't get much benefit.
If you're not sure that your CD recorder has an ATAPI-4 interface, you probably ought to put it on a separate channel from the hard drive. For information related to this topic, see "Does an old HD or CDROM slow down a new drive?", in section 5.3 of the IDE/Fast-ATA FAQ at http://www.faqs.org/faqs/pc-hardware-faq/enhanced-IDE/part1/.
The recommended configuration looks like this:
Having the CD-ROM drive and the CD recorder on the same channel doesn't necessarily prevent CD-to-CD copying, but you're still better off writing from the hard drive. At high speeds, the CPU utilization for CD-ROM drives without DMA enabled can be very high.
Keep the cables as short as you can. Sometimes the longer (60cm) cables will work fine with one drive but start having integrity problems when two devices are attached.
NOTE: early versions of the Intel PIIX Bus Mastering IDE driver may interfere with the ability to use a CD recorder. The typical symptom is a system hang when writing or test-writing to a disc. The latest version of the Intel driver (which includes an uninstaller) can be found at http://developer.intel.com/design/chipsets/drivers/busmastr/. The Adaptec page http://www.adaptec.com/support/configuration/cdrecide.html also describes the problem.
NOTE: early versions of the VIA Bus Mastering IDE drivers were similarly afflicted. See http://www.via.com.tw/support/faq.htm.
Win95/Win98 users can resolve the bus-mastering IDE driver problems by installing Win98 Second Edition (a/k/a Win98SE) after removing any manufacturer-supplied bus-mastering drivers.
The ASPI (Advanced SCSI Programmer's Interface) layer is used during CD recording, even for IDE recorders. See section (4-44) for information on how to make sure you have what you need. The original Win95A/B WinASPI may have problems with IDE recorders.
Maybe. In an ideal world, the answer would be a resounding "yes". However, some drives in some configurations will not work correctly, so the right answer is "try it and see". If you are having lots of problems getting a drive to work, turn it off. If you're running with it off, and are having performance problems, turn it on.
As with any other "try and see" procedure, don't change more than one thing at a time. For example, don't rearrange your drives and toggle DMA without doing some testing in between. Otherwise, if something breaks, you won't know which change caused it.
Under Win98, you can toggle the DMA setting by opening the Control Panel window, double-clicking on System, selecting the "System Properties" tab, expanding the "CDROM" branch, selecting the device, clicking on "Properties", clicking on "Settings", and then checking or unchecking the "DMA" checkbox. Under Win2K, you can set DMA on a per-channel basis. Under WinXP, select the adapter that the drive is on rather than the drive. Other versions of Windows may require registry tweaks.
Sometimes Win2K and WinXP will revert to PIO mode when a number of DMA errors are detected. See http://www.microsoft.com/hwdev/tech/storage/IDE-DMA.asp and http://www.gmayor.dsl.pipex.com/cd_writer_udma_mode.htm for details.
It depends on what you're doing. CD-R media is incredibly cheap these days, so using CD-RW to burn a a test disc doesn't make much sense unless you're burning a *lot* of test discs. Besides, CD-RW discs aren't readable on many older CD-ROM and audio CD players.
The manual for Easy CD Creator Deluxe v3 says that CD-RW discs are "more cost effective for near-line data storage requirements than CD-R." The definition of near-line storage puts it somewhere between online storage and offline storage.
On the other hand, if you're expecting to use packet writing to treat the disc as a big floppy, it may be useful. You should consider other forms of media for such purposes though, such as Jaz drives, which are faster and hold more, but are slightly harder to find readers for (but only slightly: CD-RW discs aren't readable on all drives, and packet-written discs may not be readable under some operating systems).
Software developers who need to create test CDs frequently will find CD-RW invaluable.
CD-Rewritable drives can write to both CD-R and CD-RW media, and because the differences in drive construction are so slight, nearly all recent recorders support both formats.
Historically, each manufacturer of CD recorders used a different command set, and perhaps even altered the commands with each new recorder. This has placed a significant burden on CD-R software authors, who have to write new drivers for each new device.
MMC (Multi Media Command) compliant recorders use a common command set. Programs that can write to one MMC-compliant recorder should be able to write to all others, and consumers should be able to use their choice of software without the long delays usually associated with the introduction of new hardware.
The reality is not so kind, unfortunately, due to firmware bugs or deliberate deviations from the standard. Do not assume that a particular piece of software will work with your recorder simply because it works for other MMC-compliant devices.
The spec sheets for recorders usually indicate whether or not the drive is MMC compliant.
The MMC-2 standard is documented in ANSI/NCITS 333-2000. You can buy a copy of the standard from http://www.ncits.org/ (specifically, http://www.techstreet.com/cgi-bin/detail?product_id=223931).
The choice of what hardware to buy is dictated by software availability. Find the software you want to use (common choices include "cdrecord", listed in section (6-1-20), GEAR in section (6-1-3), and CDR Publisher in section (6-1-9)). All support a variety of recorders, primarily SCSI devices.
Consult the software manufacturer's web site for any specific recommendations.
It's possible to get IDE recorders working under Linux, by installing an "ide-scsi" module that makes the recorder work more or less like a SCSI device. This is similar to what the Windows ASPI layer does for IDE devices. See the CD-Writing HOWTO for more details (try http://www.linuxdoc.org/HOWTO/CD-Writing-HOWTO.html).
The Sun CD FAQ at http://www.datamodl.demon.co.uk/suncd/ has some helpful tips on using CD recorders and creating bootable CD-ROMs for Solaris machines.
You need a way to connect the recorder to the laptop. After that, it's really no different from a desktop.
You can connect a typical recorder via USB (if you have a USB connector), SCSI (if you have a port or want to buy a PCMCIA SCSI card like the Adaptec 1460), FireWire (if supported or you have a PCMCIA 1394 card), or parallel port. SCSI is the fastest, but PCMCIA SCSI adapters tend to be expensive. FireWire is the next best bet. USB is a good choice, and should be available on most recent laptops, but you're limited to recording at 6x or less with USB v1.x.. Parallel port works fine, but you will probably be limited to recording at 2x.
A small selection of portable CD recorders is now available. These are small, battery-powered devices that come with a PCMCIA connection. Examples include the Ricoh MP-8040SE and Smart & Friendly Pocket RW.
In some cases it may be possible to replace the CD-ROM drive included in the laptop with a CD recorder.
Search section (5-1) for "portable" devices.
If the software options described in section (3-17) are insufficient, you may want to buy dedicated hardware. You can learn about the types of equipment available at http://www.octave.com/library/cdduplicating.html.
The purchase of a CD recorder often results in what used to be an unusual situation: a machine with two CD-ROM drives in it. This leads to a number of interesting phenomena, usually having to do with poorly-written software that can't figure out which CD-ROM drive it's supposed to use.
CD-ROM drives are typically connected to a sound card via a small cable (a couple of wires twisted together, ending in small molex connectors). This allows audio CDs to be placed in the CD-ROM drive and played through the speakers attached to the sound card. Some people, upon discovering that they have two CD-ROM drives and can use both simultaneously, want to connect both drives to the sound card's input.
This is where the trouble starts. Sound cards often only have one input. The immediate temptation is to buy or construct a Y-cable, but this won't always work. The trouble is that Y-cables only work when you have a single signal and more than one listener, like a stereo that sends its output to two sets of headphones. The situation with two CD-ROM drives is of two outputs and one listener.
Connecting two outputs together is, in general, a bad idea. Remember that electricity isn't like water: it does not come out of the output and flow downhill. The voltage at any point on the wire (ignoring minor distortions) is going to be exactly the same. So if you have a device that's trying to set it to one level, and another device that's trying to set it to another level, the two devices are going to fight, and the results aren't going to be what you want.
In some cases, if a device is inactive, it will allow its output to "float". The other device can set the voltage to whatever level it wants. So long as you only use one device at a time, all is well. Many devices, however, force the output to ground level when not in use. This generally manifests as a volume level that is almost inaudibly quiet.
Devices that combine multiple audio inputs into something reasonable are called "mixers". Buying one and embedding it into your PC case is probably not the best solution.
One possible option, if you're handy with the soldering iron, is to rig up a mechanical switch that selects which signal gets passed to the sound card. So long as you weren't planning to play two audio CDs simultaneously, this should work well.
Some sound cards have multiple connectors on them, suggesting that the card itself could handle multiple inputs. More often than not, these connectors are not electrically isolated, so even though they're not sharing the same cable they will still cause the devices to compete. If the sound card isn't advertised as allowing multiple independent inputs, don't assume it can.
Some of the Sound Blaster cards, e.g. SB Live!, do have two independent inputs ("CD in" and "AUX"). Stay away from the TAD (Telephone Answering Device) connector though, it's monaural. You may need to un-mute the auxilliary input in the volume control panel.
You can get an inexpensive Y-cable with a "passive mixer" from "Cables N Mor" at http://cablesnmor.com/cdrom.html. If you're the build-it-yourself type, some instructions for building a similar cable can be found on http://outreach.math.wisc.edu/local/miscellany/mixer.htm.
A player spinning a CD at 1x reads 75 sectors per second. On a CD-ROM, where a sector has 2048 bytes, this is exactly 150KB/sec. On an audio CD, with 2352 bytes per sector, this works out to about 172.27KB/sec. (Note for the nit-pickers: the actual bit rate is considerably higher, because of EFM, CIRC, L2 ECC, and other magic acronyms. The channel bit rate is 4.3218MHz. See Ken Pohlmann's _Principles of Digital Audio_, 4th edition, page 249.)
In terms of revolutions per minute, the answer varies depending on which part of the CD is being read. At 1x, the speed at which bits flow under the read head (the "linear velocity") needs to be fairly constant. You can get more bits in a circle at the outside of the disc than you can in a circle at the inside of the disc, because the circumference is greater. This means that the disc needs to spin more slowly (reduced "angular velocity") at the outside than it does at the inside.
To play an audio CD, you always want to be reading at 1x. This means you need a constant linear velocity that gives you 172.27KB/sec. The angular velocity changes as you move toward the outside of the disc.
To read files from a CD-ROM, you want to be reading as fast as you can. This means you'd like to maintain a constant angular velocity, spinning as fast as the spindle can go, with a linear velocity that increases as you move out to the outside of the disc. This is why a drive like the Plextor 12/20 reads at 12x at the start of the disc and 20x near the end.
In practice, there is a maximum angular velocity because of physical constraints, and a maximum linear velocity because of hardware and software constraints. This results in drives that use constant angular velocity for the first part of the disc, but limit themsleves to a maximum linear velocity. As the read head moves further out on the disc, the drive switches to constant linear velocity mode.
Devices that always spin at the same rate are called CAV (Constant Angular Velocity) drives. Devices that maintain a fixed linear velocity are called CLV (Constant Linear Velocity) drives. Devices that switch from CAV to CLV when the maximum speed is reached are called PCAV (Partial Constant Angular Velocity) drives. Most of the recent high-speed CD-ROM drives are PCAV. Devices that are CLV, but use different speeds on different parts ("zones") of the disc, are called ZCLV. Most CD recorders use CLV while writing, but some (e.g. 20x and higher) use PCAV or ZCLV.
See http://www.plextor.be/english/technical/zoneclv.html for a graph illustrating ZCLV. http://www.cdspeed2000.com/go.php3?link=faq_general.html has some nice charts showing CDSpeed output on different drive types.
You can compute how long it will take to record a disc with a CLV drive by taking the amount of data and dividing it by the record speed of the drive. A 74-minute disc will take about 19 minutes to record at 4x and a little under 10 minutes at 8x. With a PCAV drive, this calculation is no longer valid, because the velocity changes as the write head moves outward.
In terms of actual rotational speeds, a disc being read at 1x spins at about 530rpm near the center of the disc, slowing to about 200rpm at the outer edge. The linear velocity is constant, ranging from 1.2 m/s to 1.4 m/s. Discs with longer playing times (e.g. 74 minute discs vs 60 minute discs) use the slower velocity.
It has been stated that, at a rotational speed equivalent to about 50x at the outside of the disc, the polycarbonate starts to deform and the disc becomes unreadable. There have been cases of CDs shattering in high-speed drives (section (7-25)), so this figure is not totally groundless. The super-fast drives (e.g. 72x) aren't really spinning that fast; instead, they employ multiple lasers to read from more than one area on the disc at a time. A carefully-controlled set of experiments is described on http://www.qedata.se/e_js_n-cdrom.htm, the conclusion of which is that most discs fly apart at 52x (27,500rpm), and spinning at 64x is pretty much guaranteed to shatter a disc.
An unbalanced disc can cause noisy vibrations in high speed drives. Some devices will actually reduce the spindle speed if the vibrations become too severe.
Incidentally, "1x" on a DVD-ROM drive is 1353KB/sec, which is roughly 9x the speed of a "1x" CD-ROM drive. A 16x DVD-ROM drive reads at a speed equivalent to a 144x CD-ROM drive! The DVD doesn't actually spin 9x as fast, though, because the DVD "bit density" is higher. The drive can read roughly three times more data in a single revolution from a DVD than it can from a CD. (Incidentally, the 1353KB/sec figure comes from the DVD maximum user data rate of 11.08Mbps, where the 'M' is 1000*1000.) For more details, see http://www.dvddemystified.com/dvdfaq.html#4.2.
Generally speaking, no, though warnings have started to appear.
One proposed line of reasoning is that the lower reflectivity of CD-R media causes the laser to work too hard. This only makes sense for players with an AGC (Automatic Gain Control) circuit, in which the laser power adjusts automatically. This feature is generally found in newer players, because it's required for reliable playback of CD-RW discs.
It seems unlikely that a player with an AGC would fry itself while running at a valid power level, unless the device were poorly constructed. In any event, the reflectivity of CD-R is close to that of CD -- if it weren't, CD-R would have the same playback compatibility problems that CD-RW has.
The laser shouldn't have to work any harder to read CD-R. It's possible that some devices might "strain themselves" over CD-RW discs, but any device built to work with CD-RW should be able to handle the media without self-destructing.
A more likely scenario relates to differences in physical dimensions. One car dealer claimed that CD-R media is too thin, causing their 6-disc changer to occasionally grab two discs and jam itself. On the opposite end of the spectrum, some "slot-in" dashboard players will get stuck ejecting a CD-R that has had an adhesive label added, because the disc is too thick.
It's possible that the players with warnings simply don't support CD-R well for one reason or another. Rather than admit to poor construction, the manufacturers are trying to make it seem like there's something wrong with CD-R media.
Not in the sense that you can make a slow drive work faster, but in some cases you can make a speed-limited drive work at its full capacity.
Every drive model in a manufacturer's lineup costs additional money to make, because the manufacturing line has to maintain a larger inventory of parts and has to re-tool the assembly line whenever they switch production. In the world of high-volume, low-margin products, eliminating these costs can be a huge win. Changing hardware components also creates opportunities for things to fail, so every new hardware design must be extensively tested. (The above is true of many consumer electronics products, not just CD recorders.)
Some manufacturers build a high-speed drive and then use firmware to limit the drive to slower speeds. There can be technical reasons for doing this -- it's possible the parts they're using don't work well or they haven't finished getting the firmware working well at higher speeds -- but often its for marketing reasons. The higher-speed drives can initially be sold at a higher cost. If you build a 20x-capable drive, you can sell it for more than the same drive limited to 12x performance. By selling the same drive as the 12x unit and the 20x unit, you're cutting manufacturing costs even if the 20x-capable parts cost slightly more.
(CPU manufacturers typically build chips for a single speed and then sort them into speed bins based on how quickly they were able to run before they got flaky. The expensive "turbo" versions of your favorite graphics card are the same hardware as the base versions, but they ran at a faster speed without crashing. You're paying a premium for the performance boost, but it follows the laws of supply and demand: the chips that run at the highest speeds have the lowest yields, hence they cost more.)
Computer overclockers like to push the boundaries of what their components can do by assuming that the chip manufacturers put some tolerances into the bin-sorting, meaning that they can run the chip faster than rated without it becoming unstable. Or at least not *too* unstable.
With CD recorders, the speed differences might be due to hardware limitations or might be due strictly to marketing reasons. The common experience among "overclockers" is that the firmware change simply converts the drive from one kind to another. It's unclear, however, if such updates introduce more subtle problems, such as worsening the jitter present in audio recordings.
It should be pointed out that updating your drive with firmware for a different drive is VERY DANGEROUS and could result in your drive being unreliable or irrevocably dead. You should not attempt to "overclock" your recorder unless you were planning to get rid of it anyway.
Remember, this change only works on drives that were deliberately underpowered, so for many devices "overclocking" simply isn't an option. For details on performing these modifications to a variety of drives, see:
When in doubt, read the manual. If a tech support phone number is included, call it. Read section (5-15) for information on IDE configuration for a PC.
Yamaha has some interactive instructions for the PC on their site at http://www.yamaha-it.de/england/firststeps-english/index.htm. (The navigation is a little counter-intuitive, but it's okay once you get started.)
The book _CD and DVD Recording for Dummies_ by Mark L. Chambers has a section on drive selection, installation, and troubleshooting. If you're new to CD recording, the software tutorials may be helpful as well.
About the same as a CD-ROM drive, even when recording. Some simple experiments suggest that the only significant power drain occurs when the disc is spinning up. Some personal notes follow.
I connected an external Plexwriter 8/20 through a "Watts Up?" power meter. The Watts Up? device is designed for moderate loads (20W up to about 1700W) and isn't good at detecting small fluctuations, but it's accurate enough for this purpose. I connected the CD recorder and a fan drawing 50W through the meter, and subtracted 50W from the results.
When completely idle, the CD recorder and its power supply draw 8-9W. Since the recorder isn't actually doing anything, I'm guessing most of this is loss in the power supply itself. In any event, it establishes an idle-load baseline.
While playing an audio CD through the front panel headphone jack at 1X, there was no change in power usage.
While playing an audio CD through Windows Media Player, the load increased to 9-10W. I got a similar drain while extracting audio at 8x with jitter correction and at 20x without jitter correction (about 13x actual speed, according to Nero). Recording a disc at 8x gave the same result.
The only time I saw the recorder draw more than 10W (1-2W above idle) was during transitions. Inserting an audio CD gave a quick 16W pulse, and there were similar small blips at the start and end of recording the CD. Spinning up the spindle appears to draw an extra 6-7W over the idle load, but very briefly.
A drive with a higher speed rating would draw more power while spinning up, but would probably use the same amount while actually doing work. While installing Linux on a different system with an Asus 52x CD-ROM drive, I noticed the load for the entire system went from around 50W when idle to a fairly stable 90W while doing CD media verification. How much of that was the drive and how much was the CPU is unclear -- the load on the system would go from 50W to 70W when quickly raising and lowering a window under X11 -- but it's clear that there's more to the story than the drive itself.
My earlier hypothesis -- that CD recorders draw significantly more power when recording -- appears to be incorrect. There have been cases where people could do test writes but not actual writes, and solved the problem by upgrading their power supply. However, this appears to have more to do with the power supply's stability than changing load requirements. The power supply that fixed the problem may have been more reliable, or perhaps the old one was always overtaxed and the problem didn't manifest itself until something requiring precise power management was in use.
Yes, eventually. Depending on a number of factors, though, it's quite possible that your device will suffer mechanical breakdown or simply become obsolete before that happens.
There are many different ways to construct a laser diode. Different approaches result in different wavelengths, maximum power levels, and lifetimes. The lifetime of a laser is usually measured as MTTF (Mean Time To Failure) at a particular power level and ambient temperature (e.g. 10,000 hours at 5mW and 50 degrees Celsius).
Higher power levels mean higher heat dissipation -- the optical conversion efficiency of a laser diode is around 30% -- and in the semiconductor world, more heat usually equates to shorter lifetime. Recording for an hour at high speed will take a greater toll on the laser than playing a CD for an hour.
The bottom line is, there really isn't anything you can do to make the laser last longer. It'll last a very long time when used to read CDs, so there's no point in reserving the drive just for recording. It might last a little longer if you use lower recording speeds, but if you're willing to do that then why pay for a high-speed recorder?
Sony Semiconductor's "Laser Diode Guide" is available from http://www.sony.net/Products/SC-HP/laser/guide.html.
Laser diodes can suffer catastrophic failure (they suddenly stop working) or gradual degradation (reduced optical power for a given input power level). The power calibration sequence ( (4-13), (5-11)) automatically adjusts the power supplied to the laser for a given disc and write speed, so reductions in output are compensated for automatically. However, if the laser's efficiency is reduced, more DC power must be supplied, more heat is generated, and the likelihood of failure increases.
For a discussion of laser diode reliability, see http://www.bostonlaserinc.com/art1.php.
DOS, Win31, Win95, and WinNT all work well, though some recorders are more difficult to configure for Win95 and WinNT than others. (Note: Win95 and Win98 are considered equivalent here.)
Mac System 7.x works well, as should 8.x. UNIX variants (notably FreeBSD and Linux) work, but there aren't as many people using them to create CD-Rs as there are on other platforms.
If you're interested in burning CDs with long Win95 filenames, be sure to get a software package that supports Joliet (see section (3-5-4)). Otherwise all filenames get mashed down to 8+3.
Generally speaking, you get what you pay for: the more expensive software has more features. However, this isn't always the case, and the software with more features isn't necessarily more useful or more reliable.
There's little standardization among CD-R drive manufacturers, so not all devices are supported by all programs. This has changed somewhat with the development of the MMC specification, but deviations from the standard are not uncommon.
On the PC, if you're new to CD-R, start with Ahead's Nero (6-1-28) or Roxio's Easy CD Creator Deluxe (6-1-26). If you just want to "back up" CD-ROMs try CloneCD, and if you want good "backups" and lots of flexbility when creating audio CDs go with CDRWIN. If you want to write to a disc as if it were a floppy, try Roxio's DirectCD (included with ECDC; see section (6-4-1)) or Nero InCD (6-4-7).
On the Mac, go with Toast (6-1-4) or Discribe (6-1-29).
UNIX users probably ought to start with cdrecord (6-1-20) or CDRDAO (6-1-47).
Most of the software listed below is for PC running Windows. Use the search feature of your newsreader or web browser to look for "Mac" or "Linux" if that's what you're interested in.
Platforms supported: Windows (3.1, 95, NT)
[ These have been superseded by Easy CD Creator Deluxe (6-1-26). ]
The software was developed by a company called Incat, which was purchased by Adaptec in 1995.
Easy-CD Pro 95 v1.2 seems to have trouble writing umlauts and other non-ASCII characters in Joliet mode. Romeo format will work, but the files will only be accessible from Win95 and WinNT.
Platforms supported: Windows (3.1, 95, NT3.x)
[ This has been superseded by Easy CD Creator Deluxe (6-1-26). ]
The software was developed by Corel, and published by them until it was purchased by Adaptec in mid-1996. It was combined with Easy-CD Pro to form Easy CD Creator.
The package includes drivers that allow several popular CD-R drives to be used as general-purpose CD readers under Win95. It can also create VideoCD and PhotoCD discs.
Version 2.x is a considerable improvement over version 1.x. Versions older than 2.01.079 had some problems inserting "knacks" into audio CDs.
Platforms supported: DOS, Windows (95, NT, 2K), UNIX
GEAR Software was Elektroson until early 1999. It was a subsidiary of Command Software Systems, Inc. until May 2001, when it became a free-standing company.
Full-featured CD recording. Includes unattended CD copying and batch file support.
Platforms supported: Mac
The software was developed by Miles GmbH and published by Astarte until Miles was purchased by Adaptec in early 1997. In 2000 Adaptec spun the CD recording software group off into Roxio.
This program is recommended for making Mac/PC hybrids, and is the most popular package for the Mac. It supports HFS, ISO-9660, and Joliet. At one time it was sold by an OEM as "CD-It All".
The "Toast DVD" upgrade enables creation of DVD-Video and DVD-ROM.
Software updates are available on the web site.
Platforms supported: Windows
(CeQuadrat was purchased by Adaptec in July 1999, and is now part of Roxio.)
WinOnCD is the full version. WinOnCD ToGo is a "lite" version that comes bundled with some drives.
Can create VideoCD discs and bootable CD-ROMs.
Platforms supported: Windows (NT), UNIX (Linux, others)
CD recording system with a Java interface. The web site has information about specialized solutions for things like recording over Novell networks and working with CD-R jukeboxes.
Platforms supported: DOS, Windows (95, NT)
See http://www.cd-brennen.de/ (german distributor)
(CDRWIN is the name of the Win95 version. I don't believe the DOS versions have an official name.)
Contains sophisticated CD-ROM duplication programs, track-at-once and disc-at-once utilities for sound and data, and other goodies. Some of the DOS-based software is free, the rest is relatively inexpensive.
This comes highly recommended for creating audio CDs, because it gives you a great deal of control over the creation process. Updates for the software are available on the net.
The "vcache" tweak from section (4-1-2) is strongly recommended for users of CDRWIN to avoid buffer underruns.
If you use a Yamaha 200/400 and get "Logical Unit Not Ready" errors, try disabling the data caching.
Independent cue sheet editors are available from http://www.dcsoft.com/ and http://www.crosswinds.net/~cueed2000/.
Platforms supported: Windows (3.1, 95, NT), Mac
[ product has been discontinued ]
Platforms supported: Windows (3.1, 95, NT), UNIX
See http://www.cdr1.com/ (a/k/a http://www.hycd.com/)
Can create Mac/PC/UNIX hybrid CDs (i.e. CDs that work on all three platforms), as well as bootable CDs for PCs and UNIX. If you need a CD that works (and looks good) on Win95, MacOS, and UNIX, this is the program for you.
The Solaris version should be available through Sun's Catalyst program; see http://www.sun.com/sunsoft/catlink/cdr/cdrpub.htm.
Platforms supported: Windows (95, NT), UNIX (many)
Sources at ftp://ftp.fokus.gmd.de/pub/unix/cdrecord
This allows creation of an ISO-9660 filesystem on disk or tape, which can then be copied to a CD-R. It can create discs with Joliet, Rock Ridge, and HFS filenames, and can be configured to ignore certain facets of the ISO standard (like maximum directory depth). Recent versions support multisession and several kinds of bootable discs.
This can be used in conjunction with "cdrecord" (6-1-20) to write discs under UNIX. For other platforms, chances are good that your favorite CD recording application is able to write ISO-9660 images. (If not, there's probably a "cdrecord" port for your platform of choice.)
See http://sunsite.unc.edu/pub/Linux/docs/HOWTO/CD-Writing-HOWTO for a "HOWTO" guide on writing CDs under Linux.
Platforms supported: Amiga
[ product discontinued ]
(Asimware was purchased by Iomega in March 2001.)
Full-featured CD-R mastering package for the Amiga.
Platforms supported: Windows (95, NT, 2K, XP)
See http://www.ntius.com/ (demo available)
Full-featured CD creation and duplication software.
If you get "illegal request, invalid block address" complaints reading from an ATAPI CD-ROM drive, your ASPI layer may be corrupted. See the instructions in http://www.fadden.com/doc/ntius-aspi.txt.
Platforms supported: OS/2
See http://www.cirunite.com/ (demo available)
Drag-and-drop CD creation, written specifically for OS/2. Allows creation of CDs with an HPFS (OS/2) filesystem.
[ product has been discontinued? ]
Platforms supported: Windows
See http://hohnermidia.com/proaudio.html [web site gone?]
Windows-based CD-R software that has some nice features for creating audio discs, including the ability to edit the P-Q subcode data.
The "rrdemo.zip" on the web site is actually a demo of Samplitude Master from SEK´D Software. Samplitude Master is a fancy audio editing program that - among other things - allows you to create ISO-9660 images suitable for writing to a CD-R, but the demo package doesn't include software to do the actual writing (the full package includes PoINT CDaudio).
Platforms supported: DOS
CD creation software aimed at the corporate user. Comes with libraries for creating custom applications.
Platforms supported: Windows (3.1, 95)
A hardware and software combo for professional-quality sound editing, this now includes an audio CD creation tool.
Platforms supported: DOS
Pre-mastering software that supports the Rock Ridge extensions. The free demo creates ISO-9660 disc images.
Platforms supported: Amiga
CD-R creation software that supports the "AS" extensions (which preserve the Amiga protection bits and file comments).
You need AmiCDFS, CacheCDFS, AsimCDFS, or something similar to make use of the "AS" extensions. AmiCDFS is (was?) available from http://ftp.uni-paderborn.de/aminet/dirs/disk_cdrom.html. Look for amicdfs*.lha, where '*' is a version number.
Platforms supported: Windows (95, NT, 2K), Mac
A music player that includes the ability to record CDs. You can preview music and purchase it over the Internet.
Platforms supported: UNIX (several), Windows (95, NT), Mac, OS/2, BeOS, VMS, ...
A collection of freeware software and drivers for burning CDs under an impressive variety of operating systems. Source code is available. See the web site for an up-to-date list of features and supported systems. (Note the package is now called "cdrtools".)
Supports DVD-R as well.
http://sites.inka.de/~W1752/cdrecord/frontend.en.html has a comparision of front-ends for cdrecord. One of them, X-CD-Roast, is listed in section (6-1-40).
This is commonly used with "mkisofs" (6-1-10) for creating ISO images.
http://www.geocities.com/SiliconValley/Sector/5785/cdrecord/cdrecordmain.htm has an OS/2 port.
Platforms supported: Windows (95, NT)
CD mastering bundled with SCSI Rep, which allows you to write to more than one SCSI CD-R at once. See also section (3-17).
A review can be found at http://www.emediapro.net/awards/award8.html.
Platforms supported: Windows (95, NT, 2K)
See http://www.zittware.com/Products/CDMaster32/cdmaster32.html (shareware)
Specializes in recording audio CDs from MP3s.
Platforms supported: Amiga
Free CD writing tools, with source code.
Platforms supported: Windows (3.1, 95)
Full-featured CD recording.
Platforms supported: Windows (3.1, 95)
Creates audio CDs, with full control over P/Q subcodes.
Platforms supported: Windows (95, NT4, 2K)
[ Adaptec spun off Roxio as a subsidiary in 2000. All of Adaptec's CD
recording software products were moved to the Roxio label. ]Adaptec/Roxio's all-singing, all-dancing combination of Easy-CD Pro and CD Creator. Combines the best features of both and costs less, including the ability to create PhotoCDs, VideoCDs, and jewel case inserts. Also includes some new features, including an application called "Spin Doctor" that helps convert from old LPs to CD.
ECDC up to v3.5a has a "two-second truncation" problem, where extracted audio tracks end up missing two seconds. This doesn't happen for every system or every disc, but is 100% reproducible in situations where it arises. Version 3.01d fixed the problem for some users but not others.
One other note: CD Copier Deluxe in ECDC v3.x does *not* do disc-at-once recording when copying from disc-to-disc (the web site is right, the manual is wrong), but ECDC itself does. If you want to make a disc-to-disc copy with disc-at-once recording, you should set up ECDC to copy the disc without buffering to the hard drive. ECDC will refuse to use DAO if your writer doesn't support it reliably or the source drive is too slow.
Recent versions of ECDC can be used to write to 80-minute discs. For v4.x and earlier, don't use the "wizard", and ignore any complaints about being over the maximum time.
Uninstalling ECDC v4.02c up to and including v5.01 may disrupt access to CD-ROM drives under WinXP and Win2K. See section (4-49) for details. See http://www.theregister.co.uk/content/4/23448.html for an opinionated piece about the trials and tribulations of ECDC and WinXP/Win2K.
Platforms supported: Windows (95, NT)
See http://www.padus.com/ (demo available)
Allows you to write to more than one SCSI CD-R at a time. See also section (3-17).
Platforms supported: Windows (3.1, 95, NT, 2K)
See http://www.ahead.de/ (demo available)
Full-featured CD creation and duplication. Fairly popular among the Internet community.
Supports the "variable-gap track-at-once" feature of drives like the Sony 926S and Mitsumi CR-2801TE when creating CDs (but not when copying them?). Comes with "MultiMounter", which appears to be similar to Roxio's "Session Selector".
NOTE: Nero may not work correctly if DirectCD is installed. You may need to uninstall DirectCD to get Nero to work. (This was especially true with older versions of the software back in 1999, but may still be the case now.)
NOTE: Some shrink-wrapped copies of Nero that were originally bundled with CD recorders have been turning up at flea markets and computer shows. These may only support the device that they were initially sold with, but there is no such indication on the disc or packaging.
Platforms supported: Mac
CD creation for the Mac. Supports creation of hybrid CDs and disc-at-once recording. This is a popular alternative to Toast for the Mac.
Platform supported: VMS (VAX, Alpha) See http://www.cd-info.com/CDIC/Technology/CD-R/vms.html
Construct CD-ROMs under VMS.
Platforms supported: Windows (95, NT, 2K, OS/2)
CD writing with support for ISO-9660, Joliet, and Rock Ridge extensions. Uses a buffering scheme to allow drive-letter access without packet writing.
Platforms supported: Windows (95, NT), UNIX
This is a mkisofs variant that creates discs in ISO-9660 format with Joliet, Rock Ridge, and HFS extensions. HFS files can be encoded as an HFS "hybrid" or using Apple's ISO-9660 extensions.
[ This has been merged with "mkisofs" and "cdrecord", section (6-1-20). ]
Platforms supported: Windows (3.1, 95, NT), Mac
JVC's CD-R software, frequently bundled with JVC recorders.
Includes "CD-R Extensions" packet-writing software for Win31/Win95 (also known as "FloppyCD"?).
Platforms supported: Mac
An updated version of Astarte's "CD-DA" package, intended for creating professional audio CDs.
Platforms supported: Windows (95, NT, 2K)
VOB was purchased by Pinnacle Systems, Inc. in October 2002.
A package that includes:
Platforms supported: Windows (95, NT)
Fancy audio CD creation, including PQ editing and cross-fades. The original product was popular among people who regularly pre-master discs for mass production.
The product was discontinued in 1998 or so, but appears to be returning to the market in late 2002: http://biz.yahoo.com/bw/021007/70223_1.html. The new version is stand-alone rather than a SoundForge plugin.
Platforms supported: VMS (VAX, Alpha)
Construct and write CD-ROMs from VMS.
Platforms supported: Windows (95, NT)
(CeQuadrat was purchased by Adaptec in July 1999, and is now part of Roxio.)
Audio CD creation. Includes de-noise program for data digitized from tapes or records, and a layout tool for creating booklets, inlay cards, or labels.
Platforms supported: Mac
Full-featured audio CD creation.
Platforms supported: UNIX (Linux)
This is a Tcl/Tk/Tix front-end for mkisofs and cdrecord.
Platforms supported: UNIX
This is a Java front-end for cdrecord, mkisofs and cdda2wav.
Platforms supported: Windows (95, NT, 2K, XP)
Audio CD creation.
(As of mid-2002, Feurio! was also being sold on the Ahead web site.)
Platforms supported: Windows (95, NT4, 2K, XP), Mac
(Asimware Innovations was purchased by Iomega in March 2001.)
Looks to be a solid data and audio recording program.
Platforms supported: Windows (95, NT)
See http://www.dartpro.com/ (demo available)
Audio CD creation with wide support for both analog and digital sources.
Platforms supported: Windows (95, NT), Mac, UNIX (Linux, Solaris)
This is a Java application that creates hybrid disc images with Rock Ridge, Joliet, and HFS support. The image can be written with any application that can handle ISO-9660 disc images.
Platforms supported: Amiga
Simple but powerful recording for the Amiga.
[ no longer listed on their web site? ]
Platforms supported: UNIX (several), Windows (cygwin), OS/2
Linux application that does disc-at-once audio recording. Good for copying many types of discs. Source code is available.
See http://users.forthnet.gr/ath/axatis/XDuplicator/ for a GUI front-end.
Platforms supported: UNIX (several)
Business-oriented CD-recordable applications, ranging from single user CD recording to data migration and archiving with CD and DVD jukeboxes.
Platforms supported: Windows (95, ME, NT4, 2K, XP)
See http://www.elby.ch/ (demo available)
CD copier that can copy just about anything. Check the web site for a list of supported hardware.
There are some "unofficial" CloneCD discussion forums that may be of interest when trying to copy something tricky:
Platforms supported: Windows (95, NT, Linux)
See http://www.fireburner.com/ (shareware)
Simple disc recording software that takes image files (BIN/CUE, ISO, WAV) as input and writes a disc. The "binchunker" program, which converts to and from BIN/CUE files, is incorporated. Can record audio CDs from MP3s.
Platforms supported: Windows (NT, NT-Alpha), UNIX (several)
Somewhat limited recording software available for a broad range of platforms.
Platforms supported: Windows (95)
Create your own CD+G discs.
Platforms supported: Windows
Audio CD creation. Extracts audio from CDs, MP3s, LPs (via a sound card), and allows you to construct custom CDs. Also copies CD-ROMs and writes ISO images.
Platforms supported: Windows
An "Internet Music Player" that can record to CD-R.
Platforms supported: Mac
Full-featured audio CD creation for the Mac. Can do cross-fades and other fancy tricks.
Platforms supported: Windows (95)
See http://www.zy2000.com/ (shareware)
Recording application dedicated to writing MP3 songs onto CD-R.
Platforms supported: PC
Fast CD-R duplication, with support for up to 6 CD recorders running simultaneously.
Platforms supported: Windows (95, NT, 2K)
See http://www.net-burner.com/ (demo available)
Net-Burner lets you wrap up data into a self-extracting -- and self-recording -- downloadable file. For example, Music Net-Burner lets you wrap up MP3s, jewel case art, and a track listing into a single executable file. When run, the program unpacks itself and writes to a CD recorder. It does on-the-fly MP3 decoding, supports overburning, and can do disc-at-once recording. Data Net-Burner does the same sort of thing for CD-ROMs.
MP3-Burner creates audio CDs from MP3 files.
Platforms supported: Windows (95, NT, 2K)
Full-featured CD recording. Creates CDs and CD-ROMs, with all the trimmings.
Platforms supported: Windows (95, NT)
Audio restoration and CD recording. Designed specifically for transferring music from analog sources such as cassette tapes and vinyl records.
Platforms supported: Windows?
Authoring tools for VCD and SVCD.
Platforms supported: Windows
Disc copier; does "raw" reads and writes. Can be useful for analyzing copy-protected discs.
Platforms supported: Windows (XP)
Windows XP has built-in support for recording to CD-R and CD-RW. See http://www.microsoft.com/windowsxp/expertzone/columns/bridgman/august13.asp for an overview.
Platforms supported: Windows (95, ME, NT, 2K, XP)
See http://www.cd-mate.com/ (demo available)
Full-featured data and audio CD recording software. Competes with CloneCD and Nero.
Platforms supported: Windows
Disc copying and drive emulation software.
Platforms supported: Windows (95, ME, NT4, 2K, XP)
Fancy CD recording intended to compete directly against Easy CD Creator. Supports DVD+R. Includes "Drive Letter Access" packet writing software for CD+RW drives.
Platforms supported: Winodws (95, ME, NT4, 2K, XP)
Straightforward CD recording.
Software related to CD-Rs that isn't a direct part of the premastering process.
Platforms supported: Windows (3.1, 95, NT), Mac
[ product has been discontinued ]
Platforms supported: Windows
Among other things, this lets you list and extract the contents of an ISO-9660 image.
Platforms supported: Amiga
(Asimware was purchased by Iomega in March 2001.)
Allows the Amiga to read High Sierra, Mac HFS, and ISO-9660 (including Rock Ridge extensions).
[ product has been discontinued? ]
Platforms supported: UNIX
In addition to its primary role as an audio CD player for UNIX workstations, version 1.4 (still in beta) allows SPARC/Solaris2.4+ workstations to extract digital audio into ".au" files.
Platforms supported: Windows (95, NT)
Full-featured extraction and manipulation of audio data from CDs.
Platforms supported: Windows (95, NT, 2K, XP)
See http://www.arrowkey.com/ (or http://www.cdrom-prod.com/)
[ products formerly published under "Paul Crowley CD-ROM Productions" ]
Does a number of useful things, such as displaying the contents of the TOC, listing the full volume label, analyzing the media, and recovering data from "lost" sessions and hosed UDF discs.
This software is widely recommended for recovering data from otherwise unusable discs.
Platforms supported: Windows (95, NT)
Cue sheet editor for CDRWIN.
Platforms supported: Mac
Half of a CD copier. CD-Copy has a lot of features for reading CDs as images, but is unable to write them (presumably you're supposed to use Toast for that).
[ Doesn't appear to be published by www.astarte.de anymore. Doesn't seem to be part of the Roxio lineup, either. I'm told the intellectual property was purchased by Apple in 1999 or 2000. ]
Platforms supported: Windows (95, NT)
Attempts to identify the manufacturer of a CD-R disc. Reports the code from the ATIP region, which tells you who made the stamper used to create the blanks, and what kind of dye is in use. Shows the exact length of a disc.
This information may or may not be accurate; see section (2-33) for an explanation.
Platforms supported: Windows
Allows you to build CD-ROM images on a PC that are compatible with the Macintosh. Can create hybrid HFS/ISO-9660 images, ISO-9660 with Apple extension images, and pure HFS images (using the virtual filesystem image feature).
The virtual HFS partition feature allows you to create Macintosh volumes in a file on the PC, and manipulate files there.
Platforms supported: Windows
Tests various facets of CD-ROM drive performance, including DAE ability. Tables of results are available on the web site.
[ There are references to "Nero CD Speed 2000" on the web site, suggesting that the software is now related to Ahead? ]
Platforms supported: Windows
There are many programs for extracting digital audio, but EAC has become the de facto standard application for doing so. On some CD-ROM drives it can guarantee extraction of 100% perfect audio, and on most others it does as well or better than anything else available.
Platforms supported: Windows
Generates and maintains catalogs of CD and CD-ROM data, including song lists and file directories. Makes it easy to print label cards.
Platforms supported: Windows
A sound file editor with all the trimmings. Available as shareware or a commercial "Pro" version.
Platforms supported: Windows
Given a large collection of files, BTTB finds the arrangement that gets the most files onto the fewest discs.
Platforms supported: Windows
Useful utility for breaking a large WAV file into several smaller ones. Comes in handy when you're working with audio recorded from a cassette or LP and want to insert track markers.
Platforms supported: Windows
System diagnostic program, useful for making sure that your system and CD recorder are working correctly. It includes some utilities for getting technical information on your drive and on CDs.
Platforms supported: Windows
See http://www.audiograbber.com-us.net/ (demo available)
Fancy audio extraction application. Can rip to MP3 and normalize sound levels across multiple tracks.
Platforms supported: Windows
An audio capture program that looks like a sound card. After you install this software, you can tell Windows to play sound through it. A copy of the sound will be recorded to disk, making this an easy way to get perfect copies of audio from "protected" formats (e.g. encrypted Windows Media Player files or DVD-ROM).
Platforms supported: Windows
Creates and manipulates disc images in a variety of formats (ISO, BIN/CUE, CIF, NRG, others).
Packet writing is an alternative to writing entire tracks or discs. It allows you to write much smaller chunks, down to the level of individual files. With track-at-once recording there's a maximum of 99 tracks per disc, a minimum track length of 300 blocks, and an additional 150 blocks of overhead for run-in, run-out, pregap, and linking. Packet writing allows many writes per track, with only 7 blocks of overhead per write (4 for run-in, 2 for run-out, and 1 for link). Since it's possible to write packets that are small enough to fit entirely in the CD recorder's buffer, the risk of buffer underruns can be eliminated.
There are some problems with packet writing, mostly due to the inability of older CD-ROM drives to deal with the gaps between packets. CD-ROM drives can become confused if they read into the gap, a problem complicated by read-ahead optimizations on some models.
There are two basic "philosophies" behind packet writing, fixed-size and variable-size. With fixed-size packets, the CD recorder writes data whenever it has a full packet. All packets in the same track must have the same size. It's relatively easy for a CD-ROM drive to skip over the inter-packet gaps if it knows where the gaps are ahead of time, but there's a large installed base of CD-ROM drives that aren't that smart.
With variable-sized packets, the CD-ROM drive can't tell ahead of time where the gaps are. The problem can be avoided by laying out the filesystem in such a way that the drive never tries to read from the gaps. One approach is to put each file into a single packet, but if the size of a file exceeds the size of the CD recorder write buffer, the risk of buffer underruns returns. An alternative is to write the file in several pieces, but the Level 1 ISO-9660 filesystem supported by most operating systems doesn't support this. Replacing the "redirector" (e.g. MSCDEX) with one that supports Level 3 ISO-9660 solves the problem.
Files on packet-written discs are typically stored in a UDF filesystem. When the session is closed -- necessary for the disc to be readable on anything but a CD recorder -- some implementations will wrap an ISO-9660 filesystem around the disc to make the files accessible on systems without a UDF reader. When DirectCD for Windows closes a disc in ISO-9660 format, it uses Level 3 multi-extent files. Support for Level 3 ISO-9660 will likely be added to future OSs, but for the time being it can be difficult to share such discs between machines that aren't running Win95/NT.
DirectCD for Mac OS leaves the disc in UDF format, so reading the discs requires a UDF driver. See section (6-3-1) for more information on UDF, including a web site where free UDF drivers can be downloaded. (If you have DirectCD, you don't need to download the drivers separately; you would only need them if you didn't own packet-writing software and wanted to read discs created by somebody who did.)
Writing to a CD-R with packets will be slower than writing with standard premastering software. Since the expected application for packet writing is "drive letter access" rather than creating an entire CD, this should not be an issue for most people.
Audio CDs can't be written with packets.
You really don't want to defragment a CD-RW written with fixed packets. The disc is deliberately fragmented to avoid "wearing out" sectors on the disc.
Some early CD recorders were only be able to write to a disc the first 99 times it was placed in the drive, because the recorder has to calibrate the laser power before writing, and there are only 99 spaces for doing the test writes. Sony and Philips have developed ways to work around the problem, such as remembering the last 10 pieces of media seen, so this doesn't cause problems on current drives.
Information on packet-writing software follows. It is in general a bad idea to have more than one installed at the same time.
UDF is an acronym for the humbly-named "Universal Disk Format". It's a specification for a filesystem intended for use on write-once and rewritable media. It's currently being used for DVD and some of the CD-R/CD-RW packet writing software (e.g. Roxio DirectCD).
There have been four important releases of the specification:
Download free UDF 1.5 drivers for MacOS and Win95/Win98/WinNT4 from http://www.roxio.com/en/support/udfwin/index.html http://www.roxio.com/en/support/udfmac/udfmacreadme.html
(The Windows driver appears to have moved; look at the bottom of http://www.roxio.com/en/support/roxio_support/ecdc/ecdc_software_updatesv4.jhtml.)
The technical specifications for the UDF filesystem can be found at http://www.osta.org/specs/index.htm.
UDF is based on the ISO/IEC 13346 standard, now ECMA-167, which is available from http://www.ecma.ch/ecma1/STAND/ECMA-167.HTM.
Some information about ISO/IEC 13346 and ISO/IEC 13490 is at http://www.mv.com/users/kaikow/.
You can find Linux source code under development at http://trylinux.com/projects/udf/.
It depends. If your primary interests are writing audio CDs, duplicating CD-ROMs (for backups, right?), or creating CD-ROMs full of files that you can give to others, packet writing won't help you much.
Discs written by programs like Roxio DirectCD aren't usable in a CD-ROM reader until they're finalized. Finalized discs are in ISO-9660 format, but it's ISO-9660 Level 3, which not all operating systems can interpret (Win9x and WinNT can, with appropriate "redirectors" installed).
On the other hand, if you want to be able to add small amounts of data over time, it may be extremely useful. You can read the unfinalized discs on your system, so the data isn't inaccessible; it just can't be accessed on other systems that aren't also set up to do packet writing. You can overwrite files on CD-R media (the old data is still there, but the newer directory entry points to the new file), something that was very costly with multisession writes. And, of course, the risk of a buffer underrun is almost nonexistent.
Most backup software (by which I mean backing up your system, not "backing up" the latest game) uses packet writing. This can affect your ability to read backups from some operating systems, notably MS-DOS. See section (4-52).
As with CD-RW, it doesn't hurt to buy a recorder that supports it, but you're probably not missing much if you have one without it. (As of the year 2002, nearly all new recorders support both.)
Now, a reality check: sometimes packet-written discs "go funny". This could be because the CD-RW media is wearing out, or because the computer locked up when some data was pending but not yet written, or because the software has bugs. Whatever the case, DO NOT write your only copy of valuable data to a packet-written disc and keep adding stuff to it. If you do, there is a good chance you will be making a contribution to the people listed in section (6-2-6).
The format that has proven the least reliable of all CD formats is packet-written CD-RW media (which almost always uses fixed-length packets). Writing to a CD-R with variable-length packets is a big step up, especially since nothing is ever really erased from a CD-R. If it's important data, write it to a CD-R (with packet writing or, better yet, conventional disc-at-once recording) and then close the disc and don't write to it again.
Having had our reality check, I can point out that a HUGE number of people use packet writing every day, for the most part without even realizing it, and relatively few suffer for doing so. It's even integrated into operating systems like Windows XP. It's important to understand the risks and act appropriately.
There is no clear winner, but most current offerings are pretty good.
Platforms supported: Windows (95, NT, 2K), Mac
UDF-based packet writing software. Check the compatibility list on the web site to see if it works with your CD recorder and your firmware revision level.
DirectCD for Windows versions older than 1.01 conflicted with some scanners. Be sure to check the Roxio web site for the latest version. Note that DirectCD for Windows 1.x and 2.x may not support the same set of drives on all operating systems; for example, 2.0 only worked with drives capable of using CD-RW media. If you're running WinNT, you need 2.x.
NOTE: There seems to be a great deal of misinformation about how to disable DirectCD for Windows. See section (3-45) for more information.
One other note about DirectCD for Windows: in some situations you may have trouble reinstalling it. If so, try removing (or renaming) scsi1hlp.vxd, usually found in c:\windows\system\iosubsys\.
Uninstalling DirectCD v3.01 or v3.01c may disable access to CD-ROM drives under WinXP and Win2K. See section (4-49) for details.
Platforms supported: Windows
(CeQuadrat was purchased by Adaptec in July 1999, and is now part of Roxio.)
UDF-based packet writing software. Recent versions offer transparent data compression, potentially increasing the disc capacity.
Platforms supported: Windows (NT)
[ product has been discontinued? ]
Packet writing software intended for shared environments.
Platforms supported: Windows (95)
See http://www.floppycd.com/ [web site gone?]
Originally released by JVC as "CD-R Extensions".
Does variable-sized packet writing that leaves you with an ISO-9660 Level 1 CD-ROM (constrast to the ISO-9660 Level 3 disc produced by some other packet writing solutions). This should make it possible to read the finalized CDs on operating systems other than Win95/NT.
Platforms supported: Windows (95, NT, 2K)
UDF packet-writing software. Supports DVD-RAM and drag-and-drop audio CD creation. Compatible with discs created by DirectCD.
Comes with a backup package called InstantBackup.
Platforms supported: Windows (95)
Packet writing for CD-RW. Appears to be less ambitious but far simpler than its competitors.
Read-compatible with Roxio DirectCD (i.e. you can read DirectCD discs if you have this installed).
Also sold under the Sony label.
Platforms supported: Windows (95, 2K)
UDF packet-writing software. Only works with CD-RW discs.
Platforms supported: Windows (95, NT, 2K, XP)
Part of the SimpliCD package. UDF packet-writing for CD-RW discs.
[ Unclear if this is related to the SimpliCD product formerly published by Young Minds Inc. ]
Platforms supported: Windows (95, NT, 2K, XP)
See http://www.ntius.com/ (demo available)
UDF packet-writing software. Uses Windows-Explorer-style interface. Only works with CD-RW discs.
Platforms supported: Windows (98, 2K)
See http://www.hp.com/ (for HP DLA)
Most users will encounter this as HP DLA, sold with a Hewlett-Packard drive. Some documentation is available from http://www.benq.com.sg/service/cdr/manuals/veritas/DLA%20User%20Guide.pdf.
In general, no.
Do not assume that two packet-writing programs will coexist peacefully on the same system. Most won't. You may need to disable the CD recording features built into WinXP to get packet software to work.
Do not assume that discs written by one program will be readable by another. Many developers have deviated from the UDF standard when writing discs, so attempting to start a disc with one program and finish it with another is likely to end badly. It might work, it might appear to work but quietly fail, or it might fail outright.
Source code and ready-to-link libraries are available, but the more useful products tend to be more expensive. The library authors are usually CD-R software publishers themselves, and aren't about to put themselves out of business. Expect to sign a strict licensing agreement, if they agree to do business at all.
Source code for some of the packages (notably Joerg Schilling's "CD Record" and "CD Tools" by Dieter Baron and Armin Obersteiner) is available. See sections (6-1-20) and (6-1-23).
ASPI developer documentation and SDKs used to be available from http://www.adaptec.com/adaptec/developers/, but seems to have vanished. See http://www.hochfeiler.it/alvise/ASPI_1.HTM for an introduction, and ftp://ftp.adaptec.com/obsolete/adaptec/aspi_w32.txt for what's left of the Adaptec documentation.
Visit http://www.hochfeiler.it/alvise/cd-r.htm for a nice introduction to controlling a CD recorder.
Platforms supported: Windows, OS/2
API and SCSI device drivers.
Platforms supported: PC
C++ class libraries. See the web site for licensing information.
Platforms supported: Windows (95, NT, 2K, XP), UNIX (Linux, others)
16-bit and 32-bit APIs for CD-R/CD-RW, DVD, tape drives, and SCSI hard disks.
Platforms supported: Windows (95, NT)
COM/ActiveX interface to CD writing functions. Not cheap.
Platforms supported: Windows
See http://www.dialog-medien.de/html/acdwrite.ocx.html (demo available)
ActiveX/OCX interface for writing audio CDs. Develop audio CD recording applications with Visual Basic or other ActiveX environments.
Platforms supported: Windows
A utility that can be integrated into other software to provide "one-click" recording.
Platforms supported: Windows (95, ME, XP, NT, 2K)
ActiveX and COM components to develop CDR/W applications for audio and data.
Other products from the same company are CDRipperX (audio extraction), WMAEncoderX (encode WMA), MP3EncoderX (encode MP3), and VorbisEncoderX (encode Ogg Vorbis).
See section (3-20) for commentary. Remember, if you're backing up less than 650MB of data and don't need fancy features like incremental backups, you don't *need* special backup software. Just write the files to a CD-R and put it in a safe place.
For fast, occasional backups of a disk partition or an entire disk, Norton Ghost is a good way to go for PCs. If you have a second disk or multiple partitions it can be a useful way to back up your C: drive before installing something that could muck up your system (like the drivers for a Creative Labs sound card). If you want full-featured incremental and remote backups, Veritas Backup Exec is probably a good place to start.
Platforms supported: Windows (3.1, 95)
[ no longer available ]
Backup software designed to store data on CD-Rs. Allows incremental backups via multi-session writes, but backups aren't allowed to span multiple volumes. Doesn't support long filenames.
Platforms supported: Windows (95, NT)
Saves the long filenames, so that you can use backup software that only knows about short "8.3" filenames. This is an alternative to the LFNBK program that comes with Win95.
Old versions are free, new versions are inexpensive.
Platforms supported: Windows (95, NT), Mac
Dantz's Retrospect 4.0 can make use of CD-R and CD-RW by using packet writing. Useful for backing up multiple machines on a network.
Platforms supported: Windows (95, NT)
This was originally adapted for use with CD-R by Seagate Software, who appeared to have developed it out of Arcada Backup Exec. The Seagate Network and Storage Management Group was sold to Veritas in June 1999.
The consumer "Backup Exec Desktop 98" version works with Win95 and Win98. Separate versions are available for WinNT Workstation and WinNT Server.
Platforms supported: Windows (95, NT, 2K, XP), OS/2
(Looks like Ghost Software got purchased by Symantec.)
Ghost was created as a way to create boilerplate software installations and distribute them. It currently works rather well as a way of backing up an entire disk partition quickly. A "ghosted" image file can be spanned across multiple CD-Rs, and the backup set can be a bootable CD-ROM. Individual files can be extracted from the .GHO image files from a Windows application.
Platforms supported: Windows (95, NT4, 2K), DOS
Drive Image 4.0 is a hard drive cloning program that includes CD-R/CD-RW support. Images may span multiple discs. It comes with "DataKeeper" to make automatic backups easier.
Platforms supported: Windows (3.1, 95, NT)
See http://www.centered.com/ (shareware)
Second Copy maintains a duplicate of your files on a different system or removable media. It runs in the background and constantly updates the backup. Useful for maintaining an archive of a few files; not meant for full-system backups.
Platforms supported: Windows (95, NT)
See http://www.fileware.co.uk/products.htm (shareware)
Similar to Second Copy, but with a different feature set.
Platforms supported: Windows (95, NT)
Backup software that is "CD-R aware". Requires drive-letter access to the drive, which has to be provided by another program (e.g. DirectCD).
Platforms supported: Windows (95, NT)
Image-based backup software. Included with Easy CD Creator 4.
Platforms supported: Windows (95, NT, 2K, XP)
Full backup software for CD-R/CD-RW. Includes data compression and automatically spans multiple discs. Supports file-level and image-level backups.
Platforms supported: Windows (95, NT)
(CeQuadrat was purchased by Adaptec in July 1999, and is now part of Roxio.)
Backup software, included as part of WinOnCD v3.7.
Platforms supported: Windows (95, NT, 2K)
See http://www.duncanamps.com/disk2disk/ (demo available)
Inexpensive backup software for Windows. Requires drive-letter access to backup media, i.e. you need to have DirectCD or PacketCD installed. Does incremental and differential backups, and handles disc spanning.
Platforms supported: Windows (95, NT, 2K)
Packet-based backup software, included with VOB's InstantCD (6-1-35).
Platforms supported: Windows
Right click on a hard drive icon, select "Properties", click on the "Tools" tab, and then click on "Backup". With a packet-writing program installed, this should work for simple tasks.
Platforms supported: Novell
Supports access to various formats (CD-R, CD-RW, DVD+RW) via Novell NetWare. Useful for backups and disaster recovery.
Platforms supported: Windows
Easy-to-use software for backing up data files. Supports file compression and spanning of large files across multiple discs.
You must have packet-writing software already installed in your system.
When you buy retail software, you are paying for a license to use the program. Generally you are also paying for customer support that is provided at little or no additional charge.
When you buy a drive with bundled software, you are buying a version of the program for which customer support fees have not been paid. The software was provided to the hardware vendor at a reduced cost, so that the price of the package you buy is lower than the price of the drive plus the price of the software.
If you go to the store and buy the latest version of Fubar Software's Disc Writing Thing, you should contact Fubar Software for customer support. If you buy a new Frobozzco 12X SkyWriter that comes bundled with Disc Writing Thing, you will most likely be expected to contact Frobozzco with any problems you may have, because Fubar Software isn't being compensated for support costs.
This section covers recordable CD media.
The basic building blocks of CD-R media are organic dye and a reflective layer. The dye types currently in use are:
Discs come in many different colors. The color you see is determined by the color of the reflective layer (gold or silver) and the color of the dye (light blue, dark blue, green, or colorless). For example, combining a gold reflective layer with cyanine (blue) dye results in a disc that is gold on the label side and green on the writing side.
Many people have jumped to the conclusion that "silver" discs are made of silver, and have attempted to speculate on the relative reflectivity and lifespan of the media based on that assumption. Until an industry representative issues a statement concerning the actual composition, it would be unwise to assume that the reflective layer has any specific formulation.
Taiyo Yuden produced the original gold/green CDs, which were used during the development of CD-R standards. Mitsui Toatsu Chemicals invented the process for gold/gold CDs. Mitsubishi developed the metalized azo dye. Silver/blue CD-Rs, manufactured with a process patented by Verbatim, first became widely available in 1996. According to the Ricoh web site, the silver/silver "Platinum" discs, based on "advanced phthalocyanine dye", were introduced by them in 1997. They didn't really appear on the market until mid-1998 though. Kodak Japan holds the patent on formazan dye.
See section (7-3) for vague details on who manufactures what.
The reason why there are multiple formulations is that the materials and process for each are patented. If a new vendor wants to get into the CD-R market, they have to come up with a new combination of materials that conforms to the Orange Book specifications.
Some CDs have an extra coating (e.g. Kodak's "Infoguard") that makes the CD more scratch-resistant, but doesn't affect the way information is stored. The top (label) side of the CD is the part to be most concerned about, since that's where the data lives, and it's easy to damage on a CD-R. Applying a full circular CD label will help prevent scratches.
http://www.mitsuigold.com/ has some info on MTC media. You can visit http://www.ricohcorp.com/press/platinum2.htm for a press release concerning Ricoh's "platinum" media.
An EMedia Professional article discussing the composition of the newer discs is online at http://www.emediapro.net/EM1998/starrett10.html.
CD-RW discs have an entirely different composition. The data side (opposite the label side) is a dark silvery gray that is difficult to describe.
Yes. There are four factors to consider:
Some people have found brand X CD-R units work well with media type Y, while other people with the same unit have had different results. Recording a disc at 4x may make it unreadable on some drives, even though a disc recorded at 2x on the same drive works fine.
To top it all off, someone observed that discs burned with one brand of CD-R weren't readable in cheap CD-ROM drives, even though the same kind of media burned in a different device worked fine. The performance of any piece of media is always a combination of the disc, the drive that recorded it, and the drive that reads it.
A number of specific discoveries have been posted to Usenet, but none of them are conclusive. Many people have reported that Kenwood CD players don't deal with CD-Rs very well, while Alpine units play nearly everything. However, things change as product lines evolve over time.
Some users have found that the *quality* of audio recordings can vary depending on the media. Whatever the case, if you find that CD-Rs don't sound as good as the originals, it's worthwhile to try a different kind of media or a different player. See section (4-18) for other ideas.
If you want to see what media test results look like, take a look at http://www.digit-life.com/articles/cdrdisktest/index2.html.
One final comment: while there are clearly defined standards for CD-R media, there are no such standards for CD and CD-ROM drives -- other than that they be able to read CDs. It is possible for media to be within allowed tolerances, but be unreadable by a CD-ROM drive that can handle pressed discs without trouble. All you can do in this sort of situation is find a better-quality CD or CD-ROM drive, or switch to a brand of media whose characteristics are on the other side of the tolerance zone.
Taiyo Yuden made the first "green" CDs. They are now manufactured by TDK, Ricoh, Kodak, and probably several others as well.
Mitsui Toatsu Chemicals (MTC) made the first "gold" CDs. They are now manufactured by Kodak and possibly others as well.
Verbatim made the first "silver/blue" CDs.
Most CD-R brands (e.g. Yamaha and Sony) are actually made by a handful of major disc manufacturers. Attempting to keep track of who makes what is a difficult proposition at best, since new manufacturing plants are being built, and resellers can switch vendors. See section (2-33) for notes about identifying the source of a CD-R.
There is no "best" media for all recorders. You can't tell how well a disc will work just by looking at it; the only way to know is to put it in *your* recorder, write a disc, then put it in *your* reader and try it. Statements to the effect that "dark green" is better than "light green" are absurd. Some discs are more translucent than others, but that doesn't matter: they only have to reflect light in the 780nm wavelength, not the entire visible spectrum. See (7-19).
It's probably a good idea to start by selecting media that is certified for your recorder's desired write speed. See section (3-31) for some other remarks about recording speed.
Speed considerations are more important for CD-RW than CD-R. Many drives refuse to record at speeds higher than the disc is rated for. On top of that, there are "fast" blanks (for 4x-10x recording) and "slow" blanks (for 1x-4x). The "fast" blanks are labeled with a "High Speed CD-RW" logo.
The Orange Book standard was written based on the original "green" cyanine discs from Taiyo Yuden. Cyanine dye is more forgiving of marginal read/write power variations than "gold" phthalocyanine dye, making them easier to read on some drives. On the other hand, phthalocyanine is less sensitive to sunlight and UV radiation, suggesting that they would last longer under adverse conditions.
Manufacturers of phthalocyanine-based media claim it has a longer lifespan and will work better in higher speed recording than cyanine discs. See http://www.cd-info.com/CDIC/History/Commentary/Parker/stcroix.html for some notes on low-level differences between media types.
There is no advantage to using expensive "audio CD-Rs" or "music blanks". There is no difference in quality between consumer audio blanks and standard blanks from a given manufacturer. If you have a consumer audio CD recorder, you simply have no other choice. There is no way to "convert" a standard blank into a consumer audio blank. See section (5-12) for notes on how you can trick certain recorders into accepting standard blanks.
Trying samples of blanks is strongly recommended before you make a major purchase. Remember to try them in your reader as well as your writer; they may not be so useful if you can't read them in your normal CD-ROM drive.
Maxell's CD-R media earned a miserable reputation on Usenet. In April '97 Maxell announced reformulated media that seemed to work better than the previous ones. It appears they may no longer make their own media.
Some good technical information is available from http://www.mscience.com/. In particular, "Are green CD-R discs better than gold or blue ones?" at http://www.mscience.com/faq52.html.
BLER measurements for a variety of recorders and media is in a big table on http://www.digido.com/meadows.html.
See also "Is There a CD-R Media Problem?" by Katherine Cochrane, originally published in the Feb '96 issue of CD-ROM Professional.
As noted in (7-4), there is no guarantee that brand X will be the absolute best in recorder Y. However, some brands are recommended more often than others. It does pay to be brand-conscious.
Brands most often recommended: Mitsui, Kodak, Taiyo Yuden, and TDK. Sometimes Pioneer and Ricoh. It appears that HP, Philips, Sony, Yamaha, and Fuji use these manufacturers for most of their disks. (Kodak no longer manufactures media.)
Brands that are often trashed: Maxell, Verbatim, Memorex, Ritek, Hotan, Princo, Gigastorage, Lead Data, Fornet, CMC Magnetics. Many "no-name" bulk CD-Rs are one of these brands.
Sometimes a particular line of discs from a particular manufacturer or reseller will be better than others from the same company. For example, Verbatim DataLifePlus discs are recognized as pretty good, but Verbatim ValuLife are seen as being of much lower quality.
The country of manufacture may also be significant.
In humid tropical climates, care must be taken to find discs that stand up to the weather. One user reported that the data layer on Sony CDQ 74CN discs began cracking after a couple of months in an otherwise sheltered environment (e.g. no direct sunlight). Mitsubishi CD-R 700 and Melody 80 Platinum discs fared much better.
There doesn't seem to be a clear answer for CD-RW. The rest of this section applies to CD-R.
The manufacturers claim 75 years (cyanine dye, used in "green" discs), 100 years (phthalocyanine dye, used in "gold" discs), or even 200 years ("advanced" phthalocyanine dye, used in "platinum" discs) once the disc has been written. The shelf life of an unrecorded disc has been estimated at between 5 and 10 years. There is no standard agreed-upon way to test discs for lifetime viability. Accelerated aging tests have been done, but they may not provide a meaningful analogue to real-world aging.
Exposing the disc to excessive heat, humidity, or to direct sunlight will greatly reduce the lifetime. In general, CD-Rs are far less tolerant of environmental conditions than pressed CDs, and should be treated with greater care. The easiest way to make a CD-R unusable is to scratch the top surface. Find a CD-R you don't want anymore, and try to scratch the top (label side) with your fingernail, a ballpoint pen, a paper clip, and anything else you have handy. The results may surprise you.
Keep them in a cool, dark, dry place, and they will probably live longer than you do (emphasis on "probably"). Some newsgroup reports have complained of discs becoming unreadable in as little as three years, but without knowing how the discs were handled and stored such anecdotes are useless. Try to keep a little perspective on the situation: a disc that degrades very little over 100 years is useless if it can't be read in your CD-ROM drive today.
One user reported that very inexpensive CD-Rs deteriorated in a mere six weeks, despite careful storage. Some discs are better than others.
By some estimates, pressed CD-ROMs may only last for 10 to 25 years, because the aluminum reflective layer starts to corrode after a while.
One user was told by Blaupunkt that CD-R discs shouldn't be left in car CD players, because if it gets too hot in the car the CD-R will emit a gas that can blind the laser optics. However, CD-Rs are constructed much the same way and with mostly the same materials as pressed CDs, and the temperatures required to cause such an emission from the materials that are exposed would melt much of the car's interior. The dye layer is sealed into the disc, and should not present any danger to drive optics even if overheated. Even so, leaving a CD-R in a hot car isn't good for the disc, and will probably shorten its effective life.
See also http://www.cd-info.com/CDIC/Technology/CD-R/Media/Longevity.html, especially http://www.cd-info.com/CDIC/Industry/news/media-chronology.html about some inaccurate reporting in the news media.
See "Do gold CD-R discs have better longevity than green discs?" on http://www.mscience.com/faq53.html.
http://www.cdpage.com/dstuff/BobDana296.html has a very readable description of CD-R media error testing that leaves you with a numb sense of amazement that CD-Rs work at all. It also explains the errors that come out of MSCDEX and what the dreaded E32 error means to a CD stamper. Highly recommended.
Kodak has some interesting information about their "Ultima" media. See http://www.kodak.com/global/en/service/cdrMedia/index.jhtml, specifically the "KODAK Ultima Lifetime Discussion" and "KODAK Ultima Lifetime Calculation" white papers (currently in PDF format). The last page discusses the Arrhenius equation, which is used in chemistry to calculate the effect of temperature on reaction rates. The Kodak page defines it as:
t = A * exp(E/kT)where 'exp()' indicates exponentiation. 't' is disc lifetime, 'A' is a time constant, 'E' is activation energy, 'k' is Boltzmann's constant, and 'T' is absolute temperature. The equation allows lifetime determined at one temperature to be used to establish the lifetime at another. If a disc breaks down in three months in extreme heat, you can extrapolate the lifetime at room temperature.
The trouble with the equation is that you have to know either 'A' or 'E'. It appears that 'A' can be estimated based on empirical evidence, but see http://palimpsest.stanford.edu/byorg/abbey/an/an23/an23-3/an23-308.html for some cautions about how tricky it can be to choose the right value.
There are 21-minute (80mm/3-inch), 74-minute, 80-minute, 90-minute, and 99-minute CD-Rs. These translate into data storage capacities of 184MB, 650MB, 700MB, 790MB, and 870MB respectively (see below for exact figures). See section (7-14) for more about 80mm CD-Rs, and sections (3-8-1) and (3-8-2) for notes on 80-, 90-, and 99-minute blanks. There used to be 63-minute CD-Rs, but these have largely vanished.
Typical 74-minute CD-Rs are advertised as holding 650MB, 680MB, or even 700MB of data. The reality is that they're all about the same size, and while you may get as much as an extra minute or two depending on the exact construction, you're not usually going to get an extra 30MB out of a disc labeled as 74-minute media. See section (3-8-3) for information on writing beyond a disc's stated capacity.
Folks interested in "doing the math" should note that only 2048 bytes of each 2352-byte sector is used for data on typical (Mode 1) discs. The rest is used for error correction and miscellaneous fields. This is why you can fit 747MB of audio WAV files onto a disc that holds 650MB of data.
It should also be noted that hard drive manufacturers don't measure megabytes in the same way that CD-R and RAM manufacturers do. The "MB" for CD-Rs and RAM means 1024x1024, but for hard drives it means 1000x1000. Keep this in mind when purchasing a hard drive that needs to hold an entire CD. A data CD that can hold 650 "RAM" MB of data holds about 682 "disk" MB of data, which is why many CD-Rs are mislabeled as having a 680MB capacity. (The notion of "unformatted capacity" is a nonsensical myth.)
Spelled out simply:
21 minutes == 94,500 sectors == 184.6MB CD-ROM == 212.0MB CD-DAThe NIST is considering the use of different names for powers of 2, which would avoid ambiguity and disappoint lots of marketing folks. See http://physics.nist.gov/cuu/Units/binary.html.
63 minutes == 283,500 sectors == 553.7MB CD-ROM == 635.9MB CD-DA
74 minutes == 333,000 sectors == 650.3MB CD-ROM == 746.9MB CD-DA
80 minutes == 360,000 sectors == 703.1MB CD-ROM == 807.4MB CD-DA
90 minutes == 405,000 sectors == 791.0MB CD-ROM == 908.4MB CD-DA
99 minutes == 445,500 sectors == 870.1MB CD-ROM == 999.3MB CD-DA
Many CD recording programs will tell you the exact number of 2K sectors available on the CD. This is the only reliable way to know exactly how many sectors are available. 99-minute blanks may actually report incorrect values.
An informal survey conducted by one user found that the deviation between the largest and smallest 74-minute CD-R was about 3500 sectors (47 seconds, or 7MB), which while not inconsequential is nowhere near the difference between 650MB and the 680MB or 700MB figures quoted by some manufacturers. All discs had at least 333,000 sectors, as required by the Red Book specification.
http://www.cdmediaworld.com/ has a fairly detailed listing of how much data different brands of media will actually hold. Again, bear in mind that different batches of the same media may have different capacities.
The PCA (Power Calibration Area), PMA (Program Memory Area), TOC (Table of Contents), lead-in, and lead-out areas don't count against the time rating on single-session CDs. You really do get all the storage that the disc is rated for. On standard MODE 1 discs that aren't using packet writing, there is no "formatting overhead". Bear in mind, however, that the "cluster" size is 2K, and that the ISO-9660 filesystem may use more or less space than an MS-DOS FAT or HFS filesystem, so 650MB of files on a hard disk may occupy a different amount of space on a CD.
On a multisession disc, you lose about 23MB of space when the first session is closed, and about 14MB for each subsequent session. A common mistake when writing multisession CDs is to overestimate the amount of space that will be available for future sessions, so be sure to take this into account.
(If you want the details: the first additional session requires 4500 sectors for the lead-in and 6750 for the lead-out, for a total of 11250 (22.5MB, or 2.5 minutes). Each additional session requires 4500 for the lead-in and 2250 for the lead-out, for a total of 6750 (13.5MB, or 1.5 minutes). You may also need to factor 2-second pre-gaps into the size calculation for each session. On a single-session disc, the overhead for lead-in and lead-out are not counted as part of the user data area, so nothing is "lost" until you go multisession.)
Pressed aluminum CDs are also supposed to hold no more than 74 minutes of audio, but are often tweaked to hold more (see section (3-8)). To convert sectors back to seconds, divide the number of sectors by 75. If your blanks have 333,000 sectors, they have 4440 seconds, which is exactly 74 minutes.
Some packet-writing solutions will take a large bite out of your available disc space. For example, if you use Roxio DirectCD 2.x with CD-RW media, it uses fixed-length packets. This allows random file erase, which means that when you delete a file you actually get the space back, but you're reduced to about 493MB after formatting the disc. More recent versions can get closer to 531MB. See section (4-42) for more info.
Only if you're careful. The wrong kind of ink or label can damage a disc. The adhesives on some labels can dissolve the protective lacquer coating if the adhesive is based on a solvent that the lacquer is susceptible to. Asymmetric labels can throw the disc out of balance, causing read problems, and labels not designed for CDs might bubble or peel off when subjected to long periods of heat inside a CD drive. So long as you use labels that were meant for CD-R discs, you will *probably* be okay.
For the same reasons, if you want to write directly onto the surface of a disc, you want to use pens that are approved for use on unlabeled CD-R media. The ink in some kinds of pens may damage the top coating of the disc.
Specific information can sometimes be found on the back of the jewel case that the discs come in. Old TDK CDR-74 discs had the following warning:
"[...]Other brands say "use a permanent felt-tipped pen" or words to the effect that the ink shouldn't smudge. The most important part is to use a felt tip pen and not a ball-point, because the top layer of the disc will gouge easily on most media.
2. Do not attach labels or protective sheets, or apply any coating fluids to the disc.
3. When writing titles and other information on the label (gold) side of the disc, these should be written in the printed area using an oil-based felt-tipped pen.
There are pens recommended specifically for writing on CD-Rs. Examples include the Dixon Ticonderoga "Redi Sharp Plus", the Sanford "Powermark", TDK "CD Writer", and Smart and Friendly "CD Speed Marker". Some of these are relabeled Staedtler Lumocolor transparency markers (#317-9), which are alcohol-based. Never use a solvent-based "permanent" marker on a CD-R -- it can eat through the lacquer coat and destroy the disc. Memorex sells water-based color "CD Markers" in four-packs (black, blue, red, green).
Many people have had no problems with the popular Sanford "Sharpie" pens, which are alcohol-based. Other people say they've damaged discs by writing on them with a Sharpie, though those discs may have been particularly susceptible. The official word from Sanford is:
"Sanford has used Sharpie Markers on CDs for years and we have never experienced a problem. We do not believe that the Sharpie ink can affect these CDs, however we have not performed any long-term laboratory testing to verify this. We have spoken to many major CD manufacturers about this issue. They use the Sharpie Markers on CDs internally as well, and do not believe that the Sharpie Ink will cause any harm to their products.In any event, the Ultra Fine Sharpie pen looks almost sharp enough to scratch, so sticking with the Fine Point pen is recommended.
Sanford Consumer Affairs"
So long as you use the right kind of pen, it's okay to write directly on the top surface of the CD, label or no. Use a light touch -- you aren't filling out a form in triplicate. If the prospect makes you nervous, just write in the clear plastic area near the hub, or only use discs with a printable top surface.
Adding an adhesive label to a disc can make it look more "professional", but you have to be a little careful. If the label and the disc aren't a good match, the label can start to delaminate after a while.
The best way to feel confident about labeling your discs is to try it yourself. Buy some labels, put them on some discs, leave them someplace warm, and see if they peel off. If they do, you'll need a different kind of media or a different kind of label. Some labels don't adhere very well unless they're attached to a disc with a plain lacquer surface on top, so combining labels with "inkjet printable surface" media may be asking for trouble. One note of caution: this only tells you if the label will peel up right away. It doesn't tell you if the label will still be nice and flat two or three years from now, especially if you live in the tropics where the air is always hot and damp. Using adhesive labels on discs meant for long-term storage may be unwise.
Whatever you do, don't try to peel a label off once it's on. You will almost certainly pull part of the recording layer off with the label. If you're going to label a disc, do it immediately, so you can make another copy if the label doesn't adhere smoothly. Any air bubbles in the label that can't be smoothed out immediately are going to cause trouble. Use a label applicator for best results.
It may not be a good idea to put labels on discs that will be fed into a "slot in" CD player, such as those popular in dashboard car CD players. Sometimes the added thickness will cause the disc to get stuck.
A number of companies make labels for CDs, and some sell complete kits including applicators and software. Two of the biggest are NEATO, at http://www.neato.com/, and CD Stomper, at http://www.labelcd.com/. Check section (8-3) for other sources. The software from http://www.surething.com/ includes templates for a variety of different label layouts.
If you want a label that also covers up the clear plastic part at the center of the disc, search for "hub labels". There are even labels that *only* cover the hub section.
You can also buy printers that will write directly onto discs with a printable surface. One example is http://www.primeratechnology.com/, which now handles the popular FARGO CD-R label printers.
A wealth of information on CD-R labeling options can be found here: http://www.cd-info.com/CDIC/Technology/CD-R/Labeling/
Sony's http://www.sonydadc.com/ web site has a "Downloads & Templates" section with artwork that my prove useful. You can find most CD-related logos on the site (try http://www.sonydadc.com/downloads/, scroll down to "Logos" for common formats). Some are also available from http://www.licensing.philips.com/cdsystems/cdlogos.html.
Mike Richter's CD-R primer has a very nice page on labeling discs. See http://www.mrichter.com/cdr/primer/labels.htm.
It is important to keep the CD balanced, or high-speed drives may have trouble reading the disc. According to one report, a disc that had a silk-screened image on the left side of a CD-R (leaving the right half of the disc blank) was unreadable on high-speed drives due to excessive wobbling. Most label kits come with a label-centering device, usually something trivial like a stick that's the same width as the hole in the middle of the CD.
Avery's CD-R labels became quietly unavailable in October 1997. The rumor is that the adhesive caused data corruption problems, so Avery recalled them. There are indications that the adhesive would fail on some discs and start to lift off within a short period of time. If you have Avery labels (#5824) purchased before this date, you should avoid using them. The labels being produced now don't have this problem.
Disclaimer: I'm not recommending you put a CD into a microwave. CDs may contain metals that will cause your microwave to arc, destroying the microwave emitter (see cautions about metal objects in the manual for your microwave). Don't try this at home. Better yet, don't try this at all.
The basic process is, take a disc that you don't want anymore, and put it shiny-side-up on something like a coffee mug so it's nowhere near the top, bottom, or sides of the microwave. (Actually, you may want to leave it right-side-up if the disc doesn't have a label, because the foil is closest to the top of the CD.) I'm told it is important to put something in the cup to be on the safe side, so fill it most of the way with water. Try to center it in the microwave. Turn off the lights. Program the microwave for a 5-second burst on "high", and watch the fireworks.
Performing this operation on replicated CDs results in blue sparks that dance along the CD, leaving fractal-ish patterns etched into the reflective aluminum. For those of you not with the program, this also renders the CD unreadable.
Trying this with a green/gold CD-R gives you a similar light show, but the destruction patterns are different. While pressed CDs and CD-RWs don't develop consistent patterns of destruction, CD-Rs tend to form circular patterns, possibly because of the pre-formed spiral groove.
On a different note, CD-Rs seem to smell worse, or at least they start to smell earlier, than pressed CDs. The materials used are non-toxic ("cyanine" comes from the color cyan, not from cyanide), but breathing the fumes is something best avoided.
For the curious, here's a note about why they behave like they do:
"The aluminum layer in a CD-ROM is very thin. The microwave oven induces large currents in the aluminum. This makes enough heat to vaporize the aluminum. You then see a very small lightning storm as electric arcs go through the vaporized aluminum. Within a few seconds there will be many paths etched through the aluminum, leaving behind little metalic islands. Some of the islands will be shaped so that they make very good microwave antennas. These spots will focus the microwave energy, and get very hot. Now you will see just a few bright spots spewing a lot of smoke. The good part of the light show is over, turn off the oven.
I suspect that if you leave the oven going much longer, the CD-ROM will burst into flame. This will smell very bad and may do bad things to your oven and house. Don't do it."
-- Paul Haas (email@example.com), on http://hamjudo.com/notes/cdrom.html
Dreamcast GD-R discs come out just like CD-R, but DVD-R is a whole different experience.
Combining a microwaved CD-R with a tesla coil produces interesting results. See http://www.electricstuff.co.uk/cdzap.html.
If the disc wasn't closed, you can write more data in a new session. If the disc was closed, or was nearly full when the write failed but is still missing important data, then its use as digital media is over.
However, that doesn't mean it's useless. Here are a few ideas:
In one carefully controlled experiment it was determined that CD-Rs behave differently from pressed CDs when you slam them edge-on against the ground. The aluminum ones will chip (once you throw them hard enough, otherwise they just bounce) and create silver confetti. The gold one I tried chipped and the gold layer started peeling, leaving little gold flakes everywhere. One user reported that a Verbatim blue CD developed bubbles even though the plastic was intact. More experimentation is needed (but not around pets, small children, or hard-to-vacuum carpets).
On a different tack, some CD-Rs don't hold up well when immersed in water. Try pouring a little water on a disc, then let it sit until it dries. If the top surface scratches off more easily afterward, you need to be careful around moisture. Silver/blue Verbatim discs seem particularly sensitive.
One comment about snapping discs in half with your fingers: use caution. Depending on the disc and how you break it, you may end up with lots of sharp polycarbonate slivers flying through the air. Wear eye protection, be aware of people around you, and be sure to clean up all the plastic shards afterward.
If you have far more coasters than you want to play with, consider recycling them (section (7-21)).
There are many vendors. A few are listed below.
Incidentally, you have a lot of choices when it comes to CD packaging. There are single-disc jewel cases, double-sized doubles, single-sized doubles, triples, quads, sextuples, plain colors, neon colors, paper envelopes, Tyvek envelopes, cardboard sleeves, clear jewel cases with black trays, clear jewel cases with built-in trays, CD pockets for use in three-ring binders, and on, and on.
If you can imagine it, it's probably up for sale.
Some URLs to start with:
http://www.bagsunlimited.com/A warning about some double-disc jewel cases sold by CompUSA can be found at http://www.yoyo-tricks.com/CompUSA-WARNING.html (along with pictures). Apparently the pressure exerted on the hub causes cracks to appear over time. If a disc with a cracked hub is put into a high-speed drive, it may shatter (see section (7-25)).
Simply put, it's a CD-R disc with nothing printed on the top surface. Some people need "plain" discs that they can print on, or simply like them for the aesthetic value. There is no difference in quality or capacity.
If you scratched the top (label) side of a CD-R, and it no longer works, your disc is toast. (If you scratched it, and it still works, copy the data off while you still can.)
If you scratched the bottom side, then all you've done is etch the polycarbonate (plastic), and it can be repaired like any other CD. A common misconception is that the data is on the bottom, but if you examine it carefully you will see that the data is beneath the label. The laser reads the data through the polycarbonate layer, and if the layer is scratched the laser will refract onto the wrong part of the disc.
For small or radial scratches, the error correction in the CD format will allow the disc to continue working, but if there's too much disruption you will get audible glitches or CD-ROM driver errors.
If the disc works some of the time, you can "repair" it by copying it onto a new CD-R disc. If the disc is always unreadable, or is copy protected, you will need to repair the disc itself.
One product that may be useful is Wipe Out! (http://www.cdrepair.com/), a chemical abrasive that allows you to reduce scratches. Another is Discwasher from http://www.discwasher.com/.
The Repair FAQ at http://www.repairfaq.org/ has a section on repairing scratched CDs. Find the "Compact Disc Players and CDROM Drives" section, and skip down to 4.10 and 4.11. Details on using common household chemicals (e.g. toothpaste) to fill scratches can be found at http://www.btinternet.com/~zturner/.
Some people have suggested using plastic polishes or "fine cut" paint polishes sold for removing fine scratches on automobiles. These fill in the scratches and create a more optically consistent surface. Fine metal polishes may also work, and some people claim that plain old white toothpaste does the trick. There is some chance that the filler material will fall out over time, rendering the disc unreadable once again, and possibly gunking up your CD-ROM drive along the way. If you want to fill in the scratches, you should make a copy of the contents to a new disc as soon as possible, and stop using the original.
In the United States, a distinction is made between "consumer digital audio" media and data media. You have to pay extra for consumer audio CD-R blanks and DAT tapes, and the music recording industry gets a piece on the assumption that the media will be used to hold commercially recorded material.
Canada has gone a step farther, by placing a levy upon *all* media capable of storing audio. Even the "data" CD-R blanks, which don't work in consumer audio CD-recordable decks, are subject to the levy. Starting Jan 1 2001, the levy was raised from CDN$0.052 to CDN$0.21 (a 4x increase) for CD-R and CD-RW discs.
Some web sites with more information:
http://neil.eton.ca/copylevy.shtmlSee also http://www.cb-cda.gc.ca/news-e.html for a 1999/12/17 announcement that the Levy has gone into effect, and http://www.cb-cda.gc.ca/news-e.html for an announcement about the 2001 price increase.
The 80mm CD didn't catch on everywhere. In some markets, notably the USA, pressed "CD single" discs are rarely seen. The 80mm CD-R made a brief appearance, and then vanished for a while. As of the middle of the year 2000, they were once again easy to find. In mid-2001, Sony started using them in one of their Mavica camera models, and towards the end of 2001 80mm-based MP3 players appeared. They're pretty easy to find now.
Using them is not as straightforward as could be hoped. Most *software* will work just fine, because all CD-Rs have slightly different capacities, especially when you consider 63-minute, 74-minute, and 80-minute blanks. The problems stem from their physical dimensions.
Pretty much all tray-based recorders have grooves for 120mm discs and 80mm discs. However, not all of them can actually record 80mm discs. Web sites for recent drives will sometimes indicate whether or not they're compatible. Some CD recorders can read the discs but not write them, possibly because the clamping mechanism raises the disc to a level where it's no longer sufficiently supported at the edges.
If you have a caddy-based recorder, you will have a problem: while trays have two different rings for 80mm and 120mm discs, caddies don't. According to the Yamaha CDR-102 manual, there is a "Disk Adaptor", referenced as part #ADP08, that sits in the caddy and keeps the disc properly positioned. A device that performed a similar function used to be sold by music stores so that standard players could handle 80mm CD-singles; it looks like a plastic doughnut that clips onto the disc.
If you have one of these, great. If you don't, you may have difficulty finding them. You will likely have even worse luck figuring out how to play an 80mm disc on a "slot in" CD-ROM drive -- the kind where you push the disc into a slot, and it slurps it up. Some manufacturers have indicated that their traction-feed drives work fine with 80mm discs, but before you try it might be wise to have a screwdriver handy.
A less common issue with 80mm discs has to do with playback. A loose sheet included with the CDR-100/102 "CD Expert" manual states:
"An 8-cm disc recorded at normal speed on the CD Expert may not playback correctly on some manufacturer's CD-ROM drives. This is likely on drives that have a playback PLL (phase lock loop) bandwidth of 1.5 kHz. Most drives, however, have a playback PLL bandwidth of 2.5 kHz, in which case this is not a problem."The final discouragement for 80mm discs is that they only hold 21 minutes of audio (about 95250 sectors on Ritek silver-blue discs, or about 186MB), but at present cost more than their full-sized counterparts. They are an interesting curiosity, and a cute gift when placed in a miniature jewel case, but little more. There appear to be 80mm discs that hold 34 minutes (just shy of 300MB), but these come with the same caveats as 90-minute 120mm discs: the discs have to be constructed at or outside the limits of what the specifications allow, and you may have problems with compatibility.
[ On a personal note: my Plextor 8/20 refuses to accept 80mm discs when I put them in the tray. I was able to use them with a (caddy-load) Yamaha CDR-102 when I put the discs in a CD-single caddy adapter. It turns out that the Plextor 8/20 will write to the discs when the caddy adapter is used for it as well. There seems to be some problem with the Plextor's mechanics when the disc is resting in the 80mm tray. I don't know of a source for the adapters, though I'm told http://www.cddigitalcard.com/ carries them. ]
You can find CD-ROMs in many interesting shapes, including ovals and rectangles. These are functional CD-ROMs that are, for example, the same size and shape as a traditional business card (well, a really thick business card). They can have your name and contact information printed on the front, and can hold a modest amount of data, typically about 40MB.
Recordable CD-R business cards are available as well.
As with 80mm CDs (see section (7-14)), you may have trouble playing these "discs" on CD-ROM drives that use caddies or have a "slot-in" design.
Some net.vendors (there are many others, but this is a good start):
http://www.globalrendering.com/cdrom/For information about a 57.5mm disc with 80mm "wings", see http://microdiscs.de/.
Cutting a CD-R disc into a different shape isn't recommended, because the recording layer tends to delaminate easily once the seal has been broken. Some CD-Rs have appeared in Japan that use a 120mm polycarbonate disc with an 80mm recordable area. This allows the outer polycarbonate to be cut into interesting shapes without affecting the recordable area. Some pictures are available on http://www.fadden.com/cdrpics/.
What follows are some personal notes on CD-recordable business cards, based on experiments conducted in early 2000. I bought five from www.cdroutlet.com for about $3 each. According to CD-R Media Code Identifier, the essential facts are:
Nominal Capacity: 51.219MB (05m 51s 49f / LBA: 26224)The discs are gold in color, and look like an 80mm disc that was squared off across the top and bottom. They come in clear plastic envelopes that are slightly larger than the discs themselves. Total size is 80mm long and 60mm wide, which is a little off from the standard business card (88mm x 51mm) but not by much.
ATIP: 97m 1As 55f
Disc Manufacturer: Lead Data Inc.
Dye: Pthalocyanine (Type 5)
As with 80mm CD-Rs, my Plextor 8/20 rejected them unless I put them in an 80mm caddy adapter. The adapter doesn't work very well, since it's only holding the disc on two points, but it worked well enough.
I grabbed a local copy of my web page, threw on an autorun.inf and a copy of shellout.exe, and wrote it to the disc with disc-at-once recording. The recorder got upset while writing the leadout, and ECDC (3.5c) reported some fatal errors, but the disc had already been closed enough to be readable in the two CD-ROM drives tried. It's possible that the slight looseness in the caddy adapter caused problems... on future attempts I will try to fasten the disc a little more securely.
The use of these discs as business cards presents some difficulties. If you look at the picture on http://www.fadden.com/cdrpics/, you can see that the disc has the same clear hub as a standard disc, which doesn't give you much of a solid background for writing. All is not lost, however: there are other cards with ink-jet printable surfaces, and adhesive business card labels are now available.
The easiest way is to drag something sharp across the top and watch what happens. If you'd like to be able to use the disc afterward, there are some non-destructive ways too.
In some cases it's easy to tell, e.g. the color is slightly off or there are two different shades of silver. The written areas on a CD-R look slightly different from unwritten areas. A silver CD-R that has been written to capacity is nearly indistinguishable from a pressed disc though.
You can get a definitive answer with CD-R Media Code Identifier (6-2-9). Put the disc into a CD recorder and query it. Pressed discs will say "no information". Some CD recorders might have trouble finding the ATIP after the disc has been closed, so do some tests with known discs before jumping to any conclusions.
"Consumer" stand-alone audio CD recorders require special blanks. See section (5-12) for details. There is no difference in quality or composition between "data" blanks and "music" blanks, except for a flag that indicates which one it is. It's likely that "music" blanks are optimized for recording at 1x, since anything you record "live" is by definition recorded at 1x (though some dual-drive systems allow track copying at higher speeds).
You don't have to use "music" blanks to record music on a computer or on a "professional" stand-alone audio CD recorder. Nothing will prevent you from doing so, but there's no advantage to it.
The "music" blanks are more expensive than the "data" blanks because a portion of the price goes to the music industry. The specifics vary from country to country. In the USA, the money goes to the RIAA, which distributes it to artists who have navigated through a complicated application process.
Some manufacturers have on occasion marked low-quality data discs as being "for music", on the assumption that small errors will go unnoticed. Make sure that, if you need the special blanks, you're getting the right thing.
(Technically, there are actually three kinds of blanks: type 1a for CD-ROM or professional audio recording, type 1b for special-purpose applications like PhotoCD, and type 2 for unrestricted use. "Music" blanks are type 2, "data" blanks are type 1a.)
Some disc manufacturers label "music" blanks as "universal use", since they will work on anything.
The CD-Rs required by "consumer" stand-alone audio recorders ( section (5-12)) are more expensive than the standard "data" CD-Rs. Converting a standard blank into a consumer-audio blank is like converting lead to gold, in two ways: it would save a lot of money, and it's impossible.
CD-Rs have some information pressed into them that cannot be altered. One such tidbit is the Disc Application Flag, which tells the recorder what sort of blank you've inserted.
There are ways to trick certain recorders into accepting other kinds of blanks (some of which are mentioned in section (5-12)), but there is no way to disguise the blank itself.
(For the nit-pickers: apparently some experiments with nuclear reactors and particle accelerators have actually resulted in conversion of lead to gold. It is unlikely that placing a "data" CD-R in a particle accelerator will do anything useful, however.)
A popular perception is that translucent CD-R media -- discs that are, to some extent, see-through -- are lower in quality than discs you can't see through. The argument is that the discs reflect less light, and as a result are less likely to work in some players.
The argument is without merit. So long as the disc reflects at least 70% of the beam when it strikes a "land", it meets the CD-R specification.
All CD-R media, except for discs treated with an opaque top coating (usually to provide an absorbent surface for ink-jet printers), are to some extent translucent. Take your favorite brand of un-coated disc, write on the top with a black marker, and hold it up to a bright light source. The writing will be visible through the disc, even on widely recommended high-end brands.
Suppose the translucent media had an opaque label added to the top. Now that you can't see through it, is the quality of the media higher?
There is much more to media quality than its ability to reflect the visible light spectrum. It can be argued, of course, that there is a correlation between the process that yields discs that are easy to see through and discs that don't work very well. There is, as yet, no proof that such a correlation exists.
This question comes up every once in a while, because somebody with sensitive data wants to obliterate unwanted copies on CD-R. With magnetic media, the problem is well understood, and guidelines have been published for the proper treatment of floppy disks and hard drives. To the best of my knowledge, no such guidelines have been published for CD recordable media.
To be effective and useful, an approach must have two properties: it must guarantee that there is no hope of recovering any data from the media, and it must be safe and easy to implement. The qualifications for the former involve a fair degree of paranoia. If, for example, you want to erase a file from a hard drive while leaving the remaining contents intact, it is necessary to write over every sector in which the file was written several times with different bit patterns. If you just zeroed out the blocks, a sufficiently sensitive device could detect lingering magnetic traces, and possibly reconstruct significant pieces of the original file.
Some possible approaches for CD-R:
Yes. One such recycling company, Polymer Reprocessors (in the UK), has a nice web page describing what happens to the materials. Visit http://www.polymer-reprocessors.co.uk/.
Yes. It appears to be limited to tropical climates. Two articles:
The short answer is, clean them the same way you would a pressed CD. Take a lint-free cloth and wipe from the center out. It's important to move in a straight line from the hub to the outside, rather than moving in a circular motion. The act of cleaning could cause the surface to abrade, and the error correction employed is better at correcting scratches and marks that go from the center out.
You have to be a little more careful with CD-Rs than you are with pressed CDs, because the lacquer coating may not resist certain chemicals as well. Some CD-R discs all but fall apart when exposed to alcohol. Some really cheap ones start to dissolve in tap water. Your best bet is to just use a dry, clean, soft, lint-free cloth, like you would use to clean the lens of a camera.
(In practice, a wadded up tissue works pretty well.)
Yes and no. Your eyes can tell you that the disc is different, but the laser in the CD player can't.
A "black" disc, popularized by the tint added to Playstation games, has had color added to the polycarbonate layer. The tint looks very dark to the eye, but so long as it doesn't absorb or disperse too much light in the laser wavelength it won't interfere with disc performance. If you hold the disc in front of a light, you may discover that your "black" disc is actually very dark red.
Some people have suggested that, by blocking other light, the coloration enhances the performance of the disc. This makes about as much sense as drawing around the outside of the disc with a green magic marker (a popular myth from the 1980s).
If you find that "black" discs work poorly or especially well, you haven't discovered anything different from what most owners of CD recorders know: some discs just work better than others. The tint in the plastic isn't likely to be involved.
This is rare but not unheard-of. Spinning an object at high speed puts it under a lot of strain. Poorly-balanced discs can cause vibrations and make the problem worse.
http://www.rm.com/safety/ has some warnings and safety advice. There is a PDF document http://www.rm.com/safety/Downloads/StructuralIntegrity.pdf containing a thorough analysis of the problem. The study concluded that uncracked discs are not expected to shatter in 40x and 52x drives, but discs with small cracks near the hub of the disc are at risk.
If you have a disc with a visible crack in it, DO NOT use it in your CD-ROM drive unless you can reduce the speed to 8x or below (the slower the better). Not all drives can be slowed. For Plextor models use the tools that came with the drive; for some models there are speed-reduction applications available on the web; for others you're simply out of luck. Nero DriveSpeed (http://www.cdspeed2000.com/go.php3?link=nerodrivespeed.html) will work for many drives.
There is one approach guaranteed to work: put the disc in the drive. If it works, you have it right. If it doesn't, eject it and turn it over.
Alternate approach: many discs have numbers or letters printed near the hub. If they appear to be written backwards, the disc is upside-down.
Another approach: hold the disc edge-on in front of you, so you're looking right across the surface of the disc. Tilt it up slightly, and look closely at the edge farthest from you. When it's the right way up you'll just see the label, when it's the wrong way up you'll be able to see some light through the polycarbonate.
Yet another approach: the area of the disc near the hub may feel different (one side may have a groove or a lump that the other doesn't). Figure out which side is which, then remember how the disc feels.
Some of these sites have both technical information and product sales; they're listed twice.
The CD-Info bibliography at http://www.cd-info.com/CDIC/Bibliography.html is updated more frequently and will probably be more accurate than this section. It also has pointers to books, magazines, relevant areas on commercial online services, and other good stuff.
Some useful web pages. Don't forget about the newsgroups, listed in section (0-5).
NOTE: this should not be considered an endorsement of these vendors. No attempt has been made to verify the quality of products or service you will receive. This list is provided as a convenience. Dead links are occasionally weeded out.
Sources for current news on subjects relevant to CD recording. These sites are updated daily, with news and product reviews.
Much of the information contained in this FAQ was culled from the Usenet newsgroups comp.publish.cdrom.* and the WWW sites mentioned in the previous sections. All of the contents, except for a few items in "double quotes", is original material written by Andy McFadden.
Please remember that the author is NOT a CD-R expert, so sending him mail won't get you very far. Please *post* questions to comp.publish.cdrom.*.
The CD-Recordable FAQ was first posted to Usenet on March 2nd, 1996, and was made available in HTML form on www.cd-info.com on March 24th, 1996. It moved to www.fadden.com/cdrfaq/ on May 28th, 1998, and moved again to its current home on www.cdrfaq.org on March 3rd, 2001.
This FAQ was written by:
[ Due to spammers, e-mail addresses are truncated. ]
|Robert M. Albrecht||romal@---|
|Mario Diéguez B.||hidrosan@---|
|Ricardo Martinez Benesenes||Ricardo.Martinez-Benesenes@---|
|Peter 'Pedro' Blum||peter@---|
|Robert R. Boerner, Jr.||bob973@---|
|Eric Jan van den Bogaard||bogaard@---|
|Frans de Calonne||fdecalonne@---|
|Brian D. Chambers||bucknife@---|
|Steven M. Dietz||steve@---|
|Mark J. Dulcey||mark@---|
|Joe T. Fountain||gorjoe@---|
|Gary E. Grant||ggrant@---|
|Gregory F. Haas||gregh@---|
|Steven Duntley Halpape||UserNAme@---|
|Vincent van't Hoog||hoog@---|
|John J. Hook||jjh@---|
|Todd R Hustrulid||Todd.R.Hustrulid-1@---|
|Roger A. Kendall||kendall@---|
|Peter van Klaveren||Peter.van.Klaveren@---|
|Steven A. Kortze||skortze@---|
|Alexander S. Kosiorek||alex_audio@---|
|Nils Emil P. Larsen||Peter_Larsen@---|
|J. Russell Lemon||Lemon.J.Russell@---|
|Marc van Lierop||marcvl@---|
|Chris HP Lovecraft||tmservo@---|
|Jonathan Austin Maton||jmaton@---|
|Reto A. Pergher||dzkrper@---|
|Jaap v.d. Pol||jaap.van.de.pol@---|
|Phillip A. Remaker||remaker@---|
|Tonko de Rooy||tderooy@---|
|Mike "NO UCE" S.||s_c_h_u_s_t_e_r_@---|
|J. Robert Sims, III||robsims@---|
|Guy G. Sotomayor, Jr.||ggs@---|
|Jeff and Mary Spencer||spencer@---|
|Kevin Patrick Thibedeau||thibedek@---|
|Tung Cheng Tsai||thlx@---|
|Vo, Charles H.||st3wr@---|
|Kevin J. Walsh||Walsh@---|
|Gerald E. Weber||geweber@---|
|Jerome H. Whelan||whelanj@---|
|James B. Wilkinson||jimmy@---|
|OSTA CD-R Q&A||http://www.osta.org/|
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FAQ Copyright © 2003 by Andy McFadden. All Rights Reserved.