- Simon Emmerson
- and Denis Smalley
Music in which electronic technology, now primarily computer-based, is used to access, generate, explore and configure sound materials, and in which loudspeakers are the prime medium of transmission (see also Computers and music, §II). There are two main genres. Acousmatic music is intended for loudspeaker listening and exists only in recorded form (tape, compact disc, computer storage). In live electronic music the technology is used to generate, transform or trigger sounds (or a combination of these) in the act of performance; this may include generating sound with voices and traditional instruments, electro-acoustic instruments, or other devices and controls linked to computer-based systems. Both genres depend on loudspeaker transmission, and an electro-acoustic work can combine acousmatic and live elements.
Electro-acoustic music is generally regarded as a body of art-music genres that evolved from compositional techniques and aesthetic approaches developed in Europe, Japan and the Americas in the 1950s. During this decade the growing availability of magnetic tape offered composers a high-quality recording medium which allowed greater experimentation in the manipulation of recorded sounds. This music sought to expand compositional resources beyond the sounds available from instruments and voices, to explore new sound shapes and timbres both by transforming recorded sources and by synthesizing new sounds, and to break the confines of fixed pitch and metrically based approaches to rhythm....