For any combination of instruments and live computer score.
In Roomtone Variations (the resonant frequencies of the concert hall are mapped by computer, in real time, through acoustic feedback, and projected as staff notation (this takes something less than 2 minutes, and opens the performance)). The strongest, most resonant pitches appear first, at the left, the weakest at the far right. Once the staves are filled the musicians improvise variations on these notes (and some octaves) as they are highlighted, gradually stepping through a site-specific architectural tone row.
“I use a feedback system for finding the strong resonances (basically a 24 filter version of the Sabine Feedback Exterminator), and convert the fcs to their nearest tempered equivalent. I then “fold” the full range down, by octaves, to progressively narrower ranges — this latter tactic came from experiments I was doing on what I call “the fallacy of octave equivalence” (intervals change feeling with spread), about which I got into extended correspondence with Christian Wolff. The result is the closest I’ve come in 40 years to serial composition.”