audio Player for musique concrète...

[P.O.]

Hello there!
I would like to get hints as where to start/look to make a program (for OS9) for the playback of audio files in a "musique concrète" mindset...
I am using for this purpose "SoundByte": it is quite perfect for that in its ease of use, and large number of files available, but it is missing two ingredients that are very important in the "musique concrète" context: backwards playback and vari-speed.
I would suppose Quicktime has all the necessary capabilities and could be the foundation of such a device, but I have no idea how to harness this. I was thinking of MAX 4, or RealBasic. Possible?
I would be very curious to know how SoundByte is built... with the two functions added, it would be perfect! But the developper is not maintaining the OS9 version, I don't expect him to devote any energy on this...

[Naiw]

I don't remember if QuickTime supported these operations.

However if you use another language it's not all that difficult to write something that does this via the sound managers double buffer command. (Ie you manually feed sound manager the buffer you want to play, thus you can send the same buffer twice to halve the playback speed etc.)
Keep in mind that this technique alters the pitch of the music though, to avoid that you need to do FFT analysis and resynthesis which is significantly more complex but also very heavy even for the most powerful OS 9 computers.)

The big drawback is however that it won't work on OS X without additional tweaks.