sound file playback (and record) - manipulating speed + pitch in realtime?

[hsiangch_ong]

the easiest and dirtiest way.  playback with _sndraw while making computations on sample playback.  load a wave file and play back each sample frame with that procedure.  normal playback is rate of 1.  a higher rate produces a higher pitch and faster playback.  a lower rate, with a better chance one frame is played twice or more.  has issues with sound quality but it's the only way to get a lower frequency than root.  interpolation for lower pitches would only increase cpu usage.

a really fast computer would be needed to do it in realtime and to keep up with gui controls and that sort of thing.