What It is and How to Make It Using Easy-CD Pro
© 1994 Adaptec Software Products Group
Used with permission
There is a problem with the classic mixed-mode disc: the data in Track 1 can be played back (accidentally or otherwise) by most home CD audio players, with disastrous results for the listener's ears and/or speakers - the data is "played" as a very loud and grating noise. Some CD players detect a data track and either skip it or mute it, but most do not. Many CD producers who have been interested in the possibilities of putting CD-ROM data on a standard music CD have been deterred by this problem. CD Plus is a simple solution whose workability is based on the fact that most of the current generation of CD-ROM players support multisession.
A CD Plus is a two-session CD. In the first session you put up to 98 audio tracks, and you close this session as CD-DA. You then add another session containing your data track, and close that session as CD-ROM.
A consumer CD audio player plays the tracks in the first session, but when it encounters the lead-out at the end of the session it resets to zero, and never sees the second session or attempts to play the data track.
On the other hand, a multisession CD-ROM player defaults to the last session and reads the data as expected. This data includes instructions for playing the sound from the audio tracks with the usual track-relative time, and the disc performs exactly as a standard mixed-mode disc would.
It is very simple to make a CD Plus disc using Easy-CD Pro, as described below.
How to Write a CD Plus Disc
Start by writing all of your audio tracks to CD, either from a Cue Sheet or individually, as described in the chapter How to Write an Audio Disc [of the EasyCD Pro manual]. Be sure to close the session as CD-DA.
With the recordable CD still inserted in the CD recorder, proceed to write your data in the next session, either from a virtual image or from a real ISO image. Be sure to close this session as CD-ROM.
That's it - you've created a CD Plus.