Electro-acoustic music

Electroacoustic music originated in Western art music around the middle of the 20th century, following the incorporation of electric sound production into compositional practice. The initial developments in electroacoustic music composition to fixed media during the 20th century are associated with the activities of the Groupe de Recherches Musicales at the ORTF in Paris, the home of musique concrète, the Nordwestdeutscher Rundfunk (NWDR) studio in Cologne, where the focus was on the composition of elektronische Musik, and the Columbia-Princeton Electronic Music Center in New York City, where tape music, electronic music, and computer music were all explored. Practical electronic music instruments began to appear in the early 1900s, and "electronic sounds" were also produced using animation techniques by such artists as Norman McLaren.

The work of Halim El-Dabh is perhaps the earliest example of tape music. El-Dabh's The Expression of Zaar, first presented in Cairo, Egypt, in 1944, was an early work using musique concrète–like techniques similar to those developed in Paris during the same period. El-Dabh would later become more famous for his work at the Columbia-Princeton Electronic Music Center, where in 1959 he composed the influential piece Leiyla and the Poet (Holmes 2008, 153–54 & 157).

US composer John Cage's assembly of the Williams Mix serves as an example of the rigors of tape music. First, Cage created a 192-page score. Over the course of a year, 600 sounds were assembled and recorded. Cut tape segments for each occurrence of each sound were accumulated on the score. Then the cut segments were spliced to one of eight tapes, work finished on January 16, 1953. The premiere performance (realization) of the 4'15" work was given on March 21, 1953 at the University of Illinois, Urbana (Chaudron n.d.).

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