To the moderator: Delete this posting if you think it is too technical or theoretical ...

But for those who are interested in getting about 100 MB more DATA onto their CDs, read on.

First let me say: You *MUST* have a *VERY* good AUDIO reading drive (perfect DAE). If you don't have such one, don't waste your time reading this post!
All others can try to record DATA as AUDIO:
Because Audio-CDs are using less error correction than Mode1 Discs, you can store more usable data on it.

It is good to get the driver CDFS.VXD first. It allows you to access AUDIO-CDs directly from the explorer. Search for it on the web and replace it with the file located in the folder %windir%\system\iosubsys.

Now get WinRAR and compress (or just store without compression) all the files you want to have on your CD.

Create a small file containing digital silence with e.g. Cool Edit. Lengh 0.1 seconds or about 4000 samples (cut the rest if you're getting to much silence). Save this file as RAW-PCM 44100 Hz, 16 Bit Stereo.

Then merge your silence-file (it could contain noise, too) with the created RAR-archive - and this again with the silence-file:

example: DOS-Prompt: copy /b silence.raw + test.rar + silence.raw test_cdr.rar

You still get a RAR-File but with silence @ beginning AND end.

This resulting RAR-File you can burn with CDRWIN and a cuesheet which looks like:

FILE test_cdr.rar BINARY
TRACK 01 AUDIO
INDEX 01 00:00:00

The RAR archive can be about 750 MB in size depending on the CD-R you use (this guide assumes the use of a 74 min CD-R).

The burnt image is a pure audio-cd containing DATA. Please don't try the play it with your CD-Player - it doesn't sound really good. Also the autostart feature of windows is DANGEROUS!!. It could play the disc as audio.

To get back your DATA, you can open the CD with WinRAR again (Folder <drive>\Stereo\16Bit\44100Hz\Track01.wav) and extract all your files. That's it!

Why I use WinRAR:
Because CDFS.VXD interprets the CD as audio, it adds a WAVE header which MUST be ignored. Sometimes WinRAR displayes a message: RAR-Header is corrupt!. Ignore it, too ;-)

Why I add a silence file:
Because almost every CD-ROM drive has an offset. The silence @ beginning and end "protects" the DATA because the offset always will be smaller than the added file. But don't make too big silence files, WinRAR won't recognize the archive anymore!!!

Why I use CDFS.VXD:
Because it's annoying to have to copy the whole CD to get just a little file.

Tried with UltraPlex, PlexWriter 12/10/32S and Toshiba SD-M1401 (doesn't always work :-( )

At last I must say that the data security is reduced, of course.
And it is only experimental. You need *VERY* good medias and *VERY* good hardware. Try it on CD-RW if you can. So you don't have to waste your valuable CD-Rs.