Composed by Steve Riech (in 1967)

Played by Peter Aidu (1 musician 2 pianos)

Reich's phasing works generally have two identical lines of music, which begin by playing synchronously, but slowly become out of phase with one another when one of them slightly speeds up.

More info on the Peter Aidu Performance + download the 22min piece

Wikipedia on Steve Riech's Piano Phase

Found via SuperColossal