there is an object in pd called [fiddle~] which analyzes the pitch and partials of a sound. afaik, it orders the partials according to their strength, rather than pitch, but with a bit of list re-organization it would be possible to get the frequency value for a high pitched partial.<br>
<br>then it would just be a case of running a couple of bandpass filters at that frequency to isolate the sound you're after.<br><br><br><br><br>