In minimalist process music the gradually unfolding, audible process itself is the music

Minimalist process music of the 1960s-70s (Steve Reich, Terry Riley, Philip Glass) is built on the idea that a single, perceptible process, unfolding extremely gradually, both generates and constitutes the piece. Reich’s 1968 essay ‘Music as a Gradual Process’ states the goal: ‘I am interested in perceptible processes. I want to be able to hear the process happening throughout the music.’ This is the design philosophy behind generative modules like the Turing Machine: the shift register’s slow drift between random and locked (its slip zones) is exactly such a perceptible, audible process, letting the listener hear the system transform in real time rather than hearing a pre-composed arrangement.

Examples

Reich’s ‘Piano Phase’ makes a slow phase drift between two identical loops the whole piece. The Turing Machine’s 3/9-o’clock slip produces an analogous gradual, audible transformation live.

Assessment

What does Reich mean by ‘music as a gradual process’, and how does a generative device like the Turing Machine embody it? Use its slip behaviour as your example.