Experiments in musical intelligence (EMI): Non‐linear linguistic‐based composition

Abstract EMI was founded in 1983 as a project for understanding musical style. The motive for establishing it was purely selfish: the author's desire to have help in finishing a commission. He focused on how to imitate musical styles, since nothing useful could be accomplished if the computer did not understand how to produce viable music in his style. One of the components of emulating style discovered during the years of research since EMI's inception includes non‐linear composition, the focal point of this article. Results of research have been presented at the International Computer Music Conference (1987, Champaign, IL) and its resultant proceedings, at the International Symposium: Charles Ives and the American Music Tradition up to the Present (Cologne, Germany, February, 1988), the American Association of Artificial Intelligence (St. Paul, August, 1988), AIM, First International Workshop on Al and Music (Bonn, Germany, September, 1988), as well as articles in the Computer Music Journal (Winter, 1987) and Al Expert Magazine (March, 1988). Studies in the replication of musical styles have revealed that top‐down approaches to music creation produce more elegant results than linear or note‐by‐note processes. As well, object‐orientation provides an apropos venue for computer realization of non‐linear techniques. EMI uses linguistic protocols of motive and cadence properties which restrict note production. At upper levels, however, the direction of composition is decided by complex interactions between phrases, sections and even movements of a work, all nested in the basic fabric of an initial provocation (of the composition itself). Non‐linear composition has allowed creation of logical large‐scale musical forms not otherwise available from more local systems of procreating detail oriented surface strata. Since this article covers only a small portion of the EMI system, an appendix is provided to demonstrate how non‐linear techniques fit into the larger EMI algorithm.