For years David Cope's earlier books [4,5] on twentieth century music were mandatory reading for my undergraduate music composition seminar. Although these books provide neither a comprehensive history nor a well-defined theoretical treatise on compositional techniques, they both impart one concept quite beautifully: that is that music is more than simply pitches and rhythms. It is therefore surprising to read the passionate and intense diatribe regarding automated stylistic composition in Cope's recent book, Computers and Musical Style, in which a generative system based entirely on pitch and rhythmic patterns is presented.
Cope's thesis is based upon three concepts: a generalization of stylistic attributes which Cope labels signatures, a simple pattern matching method used to identify signatures, and implementation of an augmented transition network (ATN) for generating musical phrases by recycling signatures.
The book is divided into six chapters: A history of automated music and an introduction to Cope's own Experiments in Musical Intelligence (EMI) system. EM1 is a package of code that generates stylistic compositions. The package has recently been released on CD-ROM [6].
A categorization of musical style-a description of functional harmony with a seemingly obligatory incorporation of Schenkerian analysis (briefly described below) and a description of ATNs in language and in music. An introduction to LISP. An invention composing program dissected. Implementation of various Western and non-Western styles. Incorporation of user controls to create "hybrid" compositions.