Generative music

Generative music is a term popularized by Brian Eno to describe music that is ever-different and changing, and that is created by a system.

There are four primary perspectives on generative music (Wooller, R. et al., 2005) (reproduced with permission):

Music composed from analytic theories that are so explicit as to be able to generate structurally coherent material (Loy and Abbott 1985; Cope 1991). This perspective has its roots in the generative grammars of language (Chomsky 1956) and music (Lerdahl and Jackendoff 1983), which generate material with a recursive tree structure.

Music generated by a system component that has no discernible musical inputs. That is, "not transformational" (Rowe 1991; Lippe 1997:34; Winkler 1998). The Koan software by SSEYO – used by Brian Eno to create Generative Music 1 – is an example of this.

Music generated by processes that are designed and/or initiated by the composer. Steve Reich's It's Gonna Rain and Terry Riley's In C are examples of this (Eno 1996).

Non-deterministic music (Biles 2002), or music that cannot be repeated, for example, ordinary wind chimes (Dorin 2001). This perspective comes from the broader generative art movement. This revolves around the idea that music, or sounds may be "generated" by a musician "farming" parameters within an ecology, such that the ecology will perpetually produce different variation based on the parameters and algorithms used. An example of this technique is Joseph Nechvatal's Viral symphOny: a collaborative electronic noise music symphony created between the years 2006 and 2008 using custom artificial life software based on a viral model.

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