Exchange (1987)

Duration – 13’10”
Recording – Jos Zwaanenburg, flute

The relationship between soloist and accompaniment is often in the foreground in a work that involves a performer playing with pre-recorded electronic sounds as it calls into question the nature of musical performance and the role of the live performer. Works for instrument and “tape” created a revolutionary new genre of music built on the revolution of the advent of Tape Music. The Tape Music revolution created a form of music that is similar to that of film (I think this must be obvious by now and so this needs no explanation here). Instrument and Tape works combine the cinematic aspects of fixed time and content with the unpredictable nature of live performance. This has always interested me and I’ve always taken it as a unique challenge to solve the inherent problems of combining live performance with pre-recorded sound. While much of my recent work with live performers has involved live computer processing, I believe that the genre represented by Exchange still offers composers, performers, and audiences, opportunities to explore new areas of music and performance.

Exchange was composed at the Center for Computer Research in Music and Acoustics (CCRMA) at Stanford University for Australian flutist Laura Chislett in 1987. The computer part was composed using the Samson Box and a Foonly Computer, both hand-made computers, among the first specialized systems for real-time digital signal processing. They now reside in the Smithsonian Museum. It was the first work for these systems to make extensive use of digital audio filtering. Conceptually, the work is based on an idea I had to combine our traditional notions of melody, harmony, counterpoint, and sound color into a unified structure. That is, within the sonic spectra is contained the complex of wave components that make up what we hear and describe as “sound color” or timbre. Within the same complex, the spectral components sometimes unfuse and are perceived subtly as separate moving parts that emerge with their own identities only to submerge again into a fused totality. The flute rides on the surface of this ambiguous sonic texture sometimes aggressively outlining the materials as they emerge from the mass of sound and sometimes dissolving into the computer-realized sound. The flute part was composed using computer algorithms written in the Stanford Artificial Intelligence Language (SAIL). Technology aside, Exchange is a work that is at times lyrical and quite melodic and at other times features driving rhythmic virtuosity bringing the performer to the edge of their capabilities. Jos Zwaanenburg performed the flute part for this recording in London in July 2003 at the studios of the Royal College of Music.