I've used this pitch shifter quite a lot for a number of different things -- how you use it seems to depend completely on context. For instance, if you're shifting mostly sustained sounds (so that attacks aren't so present), you can use a larger window size, which reduces some of the modulation artifacts you get when you use a lower size. You need the lower size for fast things, or things with strong attacks. I once experimented with trying to get the window to match exactly period boundaries of the incoming sound (to reduce the modulation completely), but it really only works with electronic sounds where you can be absolutely sure of the frequency.

I have had luck in some rare cases mixing the output of two pitchshifters set to the same transposition but different window sizes -- again, no difference in latency, but it can help smooth things out if you're really aggressively pitchshifting something (like, by a perfect 12th), where "presence" isn't really something you're going to be able to attain anyway.

I now keep several of them around with different settings for different contexts.

Matt

Hi all,

I tried making a mult-delay pitch shifter once.  It was no good for reducing latency, but it did slightly decrease the phenomenon of double attacks one sometimes gets - but also reduces the presence of the sound, not a tradeoff I liked in the end.  I tried a bunch of other things over a period of months with no luck.

cheers Miller

On Wed, Mar 03, 2010 at 04:34:38PM +0100, Pierre Massat wrote:

...

Hi! I have been using Miller Puckette's delay-based pitch-shifter (from the audio examples) for quite a while now, and i was wondering if it would be possible to improve it a bit. In particular i'd like to reduce the delay length to lower latency (i m using it in real time). Would adding more delay lines help me solve this problem? I must say that i never took the trouble to try and understand how this patch works, so i'm not sure where to start.