patterns

The mysteries I was referring to in music are overtones; when you strike a note, it is actually made up of many notes and you hear one. When you repeat that note, or a melodic pattern, you begin to hear these overtones and they become more apparent. There are other acoustic phenomena; within a repeating pattern you may hear part of it as a separate pattern divorced from the primary one, especially when played against itself. It's only human that different people in the room might be focusing, let's say, on the higher notes within the pattern, while another group of people would be focusing on the lower notes. This might be analogous to looking at a LeWitt grid of the period, first seeing it in terms of an overall geometric figure and then as you walk around it seeing all kinds of different patterns that shift as you move.

-- Steve Reich, to Mark Godfrey, in 'Harmonious Life' Frieze 102

Steve Reich Website

Carnegie Hall's insights (via Alex Ross)