"An example of using audio to data feedback in Ableton Live.
The output of Live is fed to the patch. The patch then filters the audio in whichever way the user wants. The peak amplitude over a given interval (10ms minimum) is then sent back to Live as MIDI CC data which controls the instruments that produce the audio that is sent to the patch that generates the MIDI CC data... in other words, a feedback loop incorporating both MIDI and audio information is created."
Expect more experimentation along these lines, as i think this helps generate an organic-sounding layer of control without too much processing power or effort.