Iannis Xenakis — ST/10 and the ST algorithmic composition program

1962

Artists: Iannis Xenakis · Year: 1962 · Medium: Algorithmic musical composition — computer-generated scores for live ensemble performance · Substrate: IBM 7090 computer at IBM France Paris office; ST program written in FORTRAN by Xenakis with IBM engineers · Place: Paris, France · Institution: IBM France (computer access); CEMAMu (later) Iannis Xenakis wrote the ST program for IBM France's IBM 7090 computer in 1961–62. The program generated stochastic musical scores — pitches, durations, dynamics, and instrumentation determined by probability distributions Xenakis had specified — which were then transcribed into traditional notation and performed by live ensembles. The first published piece produced by the program, ST/10-1, 080262, is dedicated to Takemitsu and dated February 8, 1962; its title records the composition parameters (ten instruments, version 1) and the production date. ST is a sibling program to Hiller's Illiac Suite (1957) and Mathews's MUSIC I (1957) but different in its specific aim: where Hiller and Mathews were generating sound (Hiller's score was performed, but his interest was in the formal process; Mathews synthesized sound directly), Xenakis used the computer specifically to solve a compositional problem he had been working on for years — how to produce large masses of musical events whose individual details are determined by probability but whose aggregate statistical properties are controlled. His earlier orchestral work Metastasis (1954) had anticipated the approach in graphic-score form; ST made it computational. Xenakis's later UPIC system (covered separately) extended the computational approach into drawing-based composition. He is, along with Hiller and Mathews, one of the three founding figures of computer-assisted composition. He died in 2001. Lore Xenakis had trained as an architect — he collaborated with Le Corbusier on the Philips Pavilion at the 1958 Brussels Expo — before his full transition to composition. IBM France gave him mainframe access through a specific corporate-sponsored arts program in the early 1960s; the program was run out of IBM's Paris offices. The ST pieces were premiered in Paris and in international contemporary-music festivals; the scores remain in the standard Xenakis repertoire. Sources • Xenakis, Iannis — Formalized Music (Indiana University Press, 1971; revised 1992) • CEMAMu — Xenakis archive • IBM France — corporate archives