A Reconstruction of Stria

Abstract

75 John Chowning’s computer-music composition Stria premiered on 13 October 1977 in Paris, during the “Perspectives du XXe siecle” concerts. The work was commissioned in 1976 by Luciano Berio, who was then the director of IRCAM’s electroacoustic music department. John Chowning, who began thinking about this project in 1972 but without the possibility to experiment, returned to the Stanford Artificial Intelligence Lab (SAIL) and realized the piece from July to October 1977 using a DEC PDP-10 computer and the computer languages SAIL (Stanford Artificial Intelligence Language) and MUSIC 10 (similar to Music IV). The term “stria” derives from the striated aspect of the work that is so apparent in the sonogram representation. Stria is an historical piece for a number of reasons. Not least among these is its use of the intrinsic attributes of sound synthesis by frequency modulation, discovered by the composer ten years before, to structure inharmonic spectra in an ordered manner that is complementary to a nontraditional pitch space. Both the spectra and the pitch space are rooted in the Golden Ratio from antiquity (Bossis 2005). Computer-synthesized music does not require, literally speaking, traditional scores or performers. Its existence depends on techniques and devices that are not dedicated to music and become quickly obsolete. As a result, this raises two essential problems: reproduction of works and analysis of sources. (See the article by Laura Zattra in this issue; Zattra 2007.) Therefore, there is a risk that the most “ancient” music (computer music celebrates its 50th anniversary this year) may not only freeze forever in its original and low-quality recording but also become baffling even for specialists. By reconstructing Stria, I sought this double purpose: to clone the original work in a high-quality format, as well as including the possibility to modify its parameters to analyze the process. I have therefore created a computer program for reconstructing Stria, one whose interface is easy to control and customize. The complete source code will be made available on the Web; see ccrma.stanford.edu/pieces/chowning/stria.