Before you Begin

If you have already begun to use CD-R, you know all of this. It is not for you. Please skip it.

If you want to argue with any of this material, please do it somewhere else.

In short, the following is all so obvious that I'm embarassed to write it down. Still ...

1. General

  1. Most of what you 'hear' about CD-R is false.
  2. A CD-ROM reader cannot write to CD-Recordable (CD-R) media.
  3. A CD-R writer cannot write an erasable (CD-RW) blank unless it is designed to do so.
  4. Any writer can read any type of disc which it can write. That does not mean that it can read any particular disc which it has written. The ability to read depends on the medium and its contents.
  5. No CD-ROM device can read any form of DVD or DVD-ROM.
  6. No CD-R device can write any form of DVD or DVD-ROM.
  7. Any kind of file which can be stored on your hard drive can be copied to a CD-R.
  8. A file which is too big to be written to a given blank cannot be written to that blank.
  9. Certain types of information on a CD-ROM must be written in particular ways. Those include the files of Video CD (VCD) and CD Digital Audio (CD-DA).
  10. An image of the contents of any drive is not the same as the contents themselves. To recreate a CD-ROM from its image, the image must be transformed by software, not simply copied, to the CD-R.

2. Packet writing

  1. Packet writing (using UDF) requires a drive designed to write packets and packet-writing software supporting that drive.
  2. Fixed-length packets can only be written to an erasable blank in a writer designed to write packets and to write erasables - and requires software made for the purpose.
  3. If a drive is not supported for a given function by a given program, it cannot be used to do that job with that program. Exception: In some cases, a drive can be made to look like another; that will almost certainly void any warranty and may lead to unexpected and even unsolvable problems.
  4. Packet writing cannot be used to create a CD-DA or to create an exact copy of a pressed disc.
  5. If two programs require contradictory values for a parameter (such as Auto Insert Notification), they cannot both be active in a single operating system at one time. Similarly, if they require different versions of a single DLL or other component, they cannot both be active at the same time.

3. Media

  1. 'Media' is a plural noun. Its singular is 'medium'.
  2. Two blanks which have the same coloring may or may not behave the same way.
  3. There are no absolute rules for what medium is best for any specific purpose.
  4. The manufacturers and distributors of media are under no obligation to tell you what they put into their packages or to tell you when they change those contents.
  5. Erasable (RW) and write-once media work in entirely different ways.
  6. The upper (non-recordable) surface of a CD-R is delicate and must be handled with care.
  7. Never use a pencil or a ball-point or other hard-tipped pen to write onto a CD-R.
  8. In the present state of the art, two write-once media which meet the specifications may behave very differently in a recorder.
  9. The various colors of write-once media indicate differences in manufacture but do not qualify one as generally 'better' than another.

4. Readers

  1. Any device designed to read a CD, CD-ROM or CD-R is a reader. Every CD-R writer is a reader.
  2. There is no known way to write to a specific medium with a specific writer and be sure that it can be read on all readers.
  3. A reader designated MultiRead should be able to read an erasable; some which are not so designated may be able to do so as well.
  4. Some readers will not read CD-R at all.
  5. While there are reasons to prefer a reader using either SCSI or EIDE, each can perform all functions of the other.
  6. A given reader has the right to reject any given CD-R.
  7. A reader which is not a writer normally will read only a closed session.*
  8. An audio player will normally read only the first closed audio session on any disc.*

5. Writers

  1. While there are reasons to prefer a writer using either EIDE or SCSI, each can perform all functions of the other.
  2. Many features supported by some writers may not be supported by others. Some are precluded by hardware, some by firmware. In general, a feature not supported by your hardware cannot be implemented on your hardware.
  3. A hardware manufacturer may claim capability requiring software or media not supplied with the product.
  4. Not all writers are manufactured by the company whose name appears on their packaging.
  5. A writer not designed to write erasable media will not write erasable media.
  6. A writer not designed to write packets (UDF) will not write packets.
  7. In general, any modification of the hardware or firmware of a writer not sanctioned by the manufacturer will void any warranty and may result in unexpected and even unrecoverable problems.

6. Audio

  1. There are no files on an audio CD.
  2. The apparent .CDA files are a fiction of the operating system.
  3. If you see an audio CD as having WAV files, you have an artificial environment which is likely to cause problems when you work with that disc unless you know what is going on.
  4. Compact Disc - Digital Audio (CD-DA) is the fixed and inviolate format for sound which will play on a conventional stereo. It is 44.1 Ksps, two-channel, 16 bits, uncompressed PCM. With trivial exceptions, no flexibility is allowed and you cannot put more onto the disc and still play it back in a conventional machine.
  5. WAV is a file type which mastering software will convert to CD-DA when writing a CD-DA.
  6. MP3 is a file type which some mastering software will convert to CD-DA when writing a CD-DA.
  7. Whether WAV or MP3, a file which your software will not convert (e.g., at an incommensurate sampling rate) cannot be written by that software to CD-DA.
  8. Performance of a reader on audio is usually not the same as its performance on data.
  9. Converting a 44.1 Ksps WAV file to CD-DA introduces no noise, distortion or coloration to the sound. Any differences you hear are due to your ears and your hardware.

7. Summary

  1. When in doubt, read. Sources include this site, the FAQ and other sites linked from the URLS page here.
  2. CD-R technology is evolving rapidly. What was true yesterday may be false today; what is scheduled for tomorrow may never happen.
  3. The more you understand about an immature technology such as CD-R, the more likely you are to recover from any problem.
  4. CD-R problems may arise from hardware, software, firmware or procedures. Some derive from the motherboard, the adapter, reader, writer, operating system and other hardware and software on the system. Many arise from interactions of components.
  5. The most common cause of failure in writing CDs is the action or inaction of the operator.

* This condition is true by specification. It is possible for a manufacturer to create an exception so it may be false for a specific piece of hardware.

E-mail me at cdrecording@mrichter.com
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