This is a Yamaha Disklavier piano, with its MIDI out routed to a computer sequencer, running a delay octave MIDI effect, with its MIDI out routed back into the Yamaha Disklavier. This causes every keypress to be duplicated down several octaves, with delays between each note. This makes for some fun experimentation.
My nephew's friend Josh talks about working on the famed "Crazy Adventures of Josh & Sam(TM)" comics. For more information, go to:
http://www.freewe bs.com/jscomic