I want to send several streams of audio from PD into Processing. I want to use PD as the first step to split 3 or more separate frequency bands. The signal from each of these bands is then to be sent to Processing so that each band can be reacted to separately.

Processing only has a stereo pair of input channels (as far as I can tell), so I'm looking for a way to send these signals without actually routing the audio. Would anyone have any tips on how to do this? Many thanks in advance

I would do all your audio feature detection in Pd and send all your desired parameters via OSC from Pd to Processing.