Burning CD-DA (CD-Digital Audio)

This is meant to be a brief describtion of several aspects of the burning process when trying to burn an audio-CD (CD-DA). To get more in depth explanations of the different processes you'll have to confer the links at the bottom of this article.

Characteristics of Audio-CD burning:

  • CD writing is a real-time process which must run constantly without interruptions. The writing speed you select for the process will occure for the whole process.
  • The CD recorder's buffer is constantly filled with a reserve of data waiting to be written, to ensure that small slowdowns in the data-flow caused by the computer does not interrupt the writing process.
  • If the writing process is interrupted long enough for the buffer to being emptied, the writing will be halted, and the CD-R will be ruined and unusable.
  • The CD-DA format is a so called "RedBook" format, which in brief means that it is playable on a standard udio CD-player on a Hi-Fi system. The audio data-files stored on the disc is a PCM wav-file at 16bits format at a sampling rate of 44.1 kHz (44100 samples per second). Pretty fast you might say, and therefore be very dependant on a capable computer and transfer setup.

 

Preparations and considerations when burning (in unprioritized order) 

  • Stop the computer from doing anything else than the writing.
    • Disable virus scanning
    • Disable internet
    • Disable CD-autorun (Auto Insert Notification)
    • Stop all background tasks like power saving, screen savers, MS Fast Find and any scheduling tasks as auto defrag or similar.
    • Close all open programs other than the softwares you need for the CD writing.
  • Prepare your HD
    • Defragment your HD, you should do it once a week anyway (fragmentation of the files requested for writing will slow down the data transfer).
    • Make sure that you have enough free space in the temporary directory, at least twice the size of the largest file you're going to record.
    • Don't use HD's or HD's partitions that is compressed as storage for the audio files or CD images you're going to burn. It may cause buffer underrun.
    • If you have the option to do so, use a fast HD (7200 rpm) and CPU (the more Hz the better) as possible.
  • The CD-R disc and the CD-recorder/burner
    • Clean CD-R disc making sure the disc is free from dust and fingerprints.
    • Clean the CD-recorder if it is necessary or possible, and keep the recorder as free from dust as possible.
    • Don't use CD-RW discs. You may record onto them but they will not be playable on a CD-player afterwards.
    • Don't write more than 70 minutes discs.
    • Ensure that the CD-R's are made for audio and the speed you're going to record at.
    • Make sure you are using the latest drivers for your burning software.
  • The writing process
    • Burn the CD at low speed. Older advices says 2x, but today recorders and computers are perfectly up to the task of burning at at least 4x. I myself have made a lot of audio CD copies at both 8x and even 12x with satisfactory results.
    • Preferably write to HD before the burning process.
    • Use "Disc at once" not "Track at once".
    • NB:
      • Don't tuch the computer nor the mouse during the writing process.
      • Make sure that the computer is not exposed to shakings of any kind .
      • Do not record cross any network. Copy files to the local HD if necessary.
      • Do not try to record:
        •    Empty directories
        •    Zero byte files
        •    Files that may be in use by the system during the time of recording
    • If necessary, write from a CD-image rather than "Disc on the fly".
    • Put the CD-R into the recorder and wait a couple of seconds, for the recorder to speed up and prepare for action, before executing the writing.

 

Causes of errors (Not mentioned above)

  • Instabillity in the recorder's clock-timing may cause what is called jitter. This kind of jitter may also be a result of sync discrepancies between the read and write stages, especially when you're useing different recorders for the two processes.
  • Every data burning process will imply errors caused by the very high demand for
    precission in the process. Therefore the burning softeware and the CD format standard
    is equipped with a Error-correction functionallity. This error-correction will
    in some way restore the file or interpolate missing bits and bytes. Dirty CD's
    may result though in errors that the drive woun't be able to interpolate.
  • When getting errors you should allways consider a malfunction of the recorder
    too. Maybe it's an old one, or a heavy used one that needs cleaning or service?
    Or simply broke!

 

This was a brief, and not very accurate describtion of some of the aspects of burning an Audio-CD. If you want more information on the subject or more in depth explanations go to the following sites:

CD-Recordable FAQ - main page ...(by Andy McFadden, 2003)

(NB: To get to the various pages change the --/faq01.html to --/faq02.html and so on)

© 2005 Jon Buer