This software MIDI Controller allows you to generate and send polyphonic aftertouch messages to your synthesiser without the need for a poly aftertouch keyboard or an MPE device. If your synth supports polyphonic aftertouch but you don't have a poly AT keyboard then PPG can open up creative options for you that would otherwise not be possible. And if you own a monophonic aftertouch keyboard PPG can get you as close to the poly aftertouch experience as is physically possible.