Live Electronics

Live electronic music generally utilizes instrumental or electronic sounds but excludes those that have been prerecorded (Sutherland 1994). The timbres of the various sounds may then be transformed extensively during performance using devices such as amplifiers, filters, ring modulators and other forms of circuitry.

During the 1960s, a number of composers believed studio-based composition lacked elements that were central to the creation of live music such as spontaneity, dialogue, discovery and group interaction (Sutherland 1994, 157).

Although live electronics became the primary area of innovation in electronic music in the 1970s, there are precedents dating back to the 1930s in some experimental compositions of John Cage (Simms 1986, 395).

Source : http://en.wikipedia.org/wiki/Live_electronic_music