Music Sound

Generative music. There are four primary perspectives on generative music that have slightly different but related meanings (Wooller et. al., 2005):

1. Linguistic/Structual: music composed from analytic theories that are so explict 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.

2. Interactive/Behavioural: music generated by a system component that ostensibly has no inputs. That is, 'not transformational' (Rowe 1991; Lippe 1997:34; Winkler 1998).

3. Creative/Procedural: music generated by processes that are designed and/or initiated by the composer. Steve Reich's Its gonna rain and Terry Riley's In C are examples of this (Eno 1996).

4. Biological/Emergent: 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.

• Lerdahl and Jackendoff's publication described a generative grammar for tonal music, based mostly on a Schenkerian model, that could be automated to produce tonal counterpoint of any length which obeys certain structural principles at many levels.

• In Its gonna rain, overlapping tape loops of the spoken phrase "it's gonna rain" are played at slightly different speeds, generating different patterns through phasing.

• Brian Eno has used generative techniques on many of his works, starting with Discreet Music (1975) up to and including (according to Sound on Sound Oct 2005) his latest album 'Another Day on Earth'. His works, lectures, and interviews on the subject have done much to promote generative music in the avant-garde music community.

• Many software programs are now available to create generative music, such as SSEYO's Koan Pro (1994-2005) (used by Brian Eno to create his hybrid album 'Generative Music 1'), Karlheinz Essl's Lexikon-Sonate (1992-2004) and MusiGenesis (2005), a program that evolves music. In 2004, software such as SSEYO's miniMIXA started to appear that allows users of connected devices such as mobile phones and PDAs to create and experience generative music 'on-the-move'. Lauri Gröhn has developed Synesthesia software that generates music from any pictures in a few seconds.

• The madplayer uses generative techniques to create electronic music, as does LEMu (Live Electronic Music). Many algorithmic music projects are also considered to be generative. algorithmic.net comprehensively maps them.

References

Biles, A. 2002a. GenJam in Transition: from Genetic Jammer to Generative Jammer. In International Conference on Generative Art, Milan, Italy.

Chomsky, N. 1956. Three models for the description of language. IRE Transcripts on Information Theory, 2: 113-124.

Cope, D. 1991. Computers and musical style. Madison, Wis.: A-R Editions.

Dorin, A. 2001. Generative processes and the electronic arts. Organised Sound, 6 (1): 47-53.

Eno, B. 1996. Generative Music. http://www.inmotionmagazine.com/eno1.html (accessed 27th of July, 2005).

Lerdahl, F. and R. Jackendoff. 1983. A generative theory of tonal music. Cambridge, Mass: MIT Press.

Lippe, C. 1997. Music for piano and computer: A description. Information Processing Society of Japa SIG Notes, 97 (122): 33-38.

Loy, G. and C. Abbott. 1985. Programming languages for computer music synthesis, performance and composition. ACM Computing Surveys (CSUR), 17 (2): 235-265.

Rowe, R. 1991. Machine Learning and Composing: Making Sense of Music with Cooperating Real-Time Agents. Thesis from Media Lab. Mass.: MIT.

Winkler, T. 1998. Composing Interactive Music. Cambridge, Massachusetts: MIT Press.

Wooller, R., et al. A framework for comparing algorithmic music systems. in Symposium on Generative Arts Practice (GAP). 2005. University of Western Sydney.