Re: Pitch-shifting percussion sounds & Latency rant

["Dennis Leas" <dennis@mdbs.com>]

> > There should be no delay of the pitch-shifted signal (very important
since I
> > want to use it for rhythms)
>
> Unfortunately delay is always present to some extent when pitch shifting.
> Pitch shifting works by dividing the sound into chunks, and playing back
> those
> chunks at a different speed.

Yes!  There will always be some amount of delay.

The pitch shifter that you describe is certainly one technique.  It's sort
of a granulation technique.

Another technique is to perform a live spectral analysis then do a
resynthesis on the result.  But between the two, you scale the frequency.
This also preserves the formant structure of the sound so you don't get the
"Mickey Mouse" effect.  On my Kyma system I observe about a 68 millisecond
delay with this technique.

The analysis/resynthesis technique also has other interesting properties.
For example, you don't have to use sine waves for resynthesis; you can pick
any kind of waveform.

Dennis Leas
-------------------
dennis@mdbs.com