Music composed completely or partly of electronically generated and/or modified sounds. The term was first used in 1954 to describe music made up of synthesized sounds recorded on tape, to distinguish it from musique concrète (‘concrete music’), but later included music for electronic sounds with traditional instruments or voices.
Karlheinz Stockhausen was a pioneer of electronic music, and his Gesang der Jünglinge/Song of the Youths (1955–56), for boys' voices and electronic sounds, was one of the first important pieces in this style. Luciano Berio also composed music using a mixture of electronic and traditional instruments, such as Differences (1957) for chamber ensemble and tape. Other composers working in the early years of electronic music were Milton Babbitt, Bruno Maderna, and Edgard Varèse, the latter being a very early pioneer.
The development of portable electronic instruments in the late 1950s meant that electronic music could be played live and no longer had to be created in a studio and recorded on tape. Computer technology has also greatly improved the range and versatility of electronic instruments. Composers such as Pierre Boulez and Iannis Xenakis have written electronic pieces using the latest computer technology, and many other composers now incorporate electronic instruments in their work.
Early electronic music The synthesis (construction) of musical sounds was first made possible early in the 20th century by the invention of the thermionic valve. The first experiments in this field gave rise to various musical instruments such as the theremin, ondes martenot, and electronic organ, in which the sound is produced by means of oscillators, transformed by filters, and fed out of loudspeakers. The development of ‘pure’ electronic music only came about after the perfection of the tape recorder in 1950; before then electronic instruments tended to be used to augment traditional ensembles or as solo instruments mimicking or replacing acoustic ones, and no distinctive style for these new instruments had been developed.
The Cologne studio In 1951 a studio was set up at Cologne Radio under the direction of Herbert Eimert. Its aim was to use only sounds synthesized by electronic oscillators as the raw material for electronic manipulation. This differed from the musique concrète practised in Paris, which used only external sounds, both musical and unmusical, for its material. However, the methods of managing these two sorts of material were similar, making use of electronic filters, intensity control, reverberation, and tape manipulation. One of the most important composer pioneers in the field was Stockhausen, who was director of the Cologne studio from 1963. His later compositions, such as Mikrophoponie I (1964) and Mikrophoponie II (1965), and work by other composers in the Cologne studio went further in the direction of using external sounds as well as pure electronic sound, thus merging musique concrète and pure electronic music. In the late 1950s composers began to use prerecorded electronic music with ‘live’ instruments in pieces such as Stockhausen's Kontakte for piano, percussion, and tape (1959–60).
Equipment A typical electronic music studio of that time would contain a number of oscillators or sound sources, producing basic wave forms and noise, and a number of devices for treating these sound sources: filters, to alter the tone quality of a sound by eliminating or emphasizing certain harmonics in its harmonic series; envelope shapers, to control the attack, duration, and intensity curve of a sound; reverberation units, to provide resonance; and ring modulators, by which one sound modulates another to produce dramatic changes in quality. In addition, very slow wave forms were used to control the pitch, intensity, duration, timbre, and other parameters of the sounds generated by the oscillators, allowing a certain amount of preprogramming of the studio without the aid of computer techniques.
Computers and electronic music After 1960, with the arrival of the purpose-built synthesizer developed by Bob Moog, Peter Zinovieff, and others, a greater interest developed in computer-aided synthesis, which resulted in the installation of the 4X system at the Institut de Recherche et de Coordination Acoustique-Musique (IRCAM) in Paris. The use of computers in electronic music has introduced greater flexibility, allowing whole compositions to be programmed and stored in memory banks. This, along with the arrival of digital recording techniques, has eliminated the need for laborious tape editing. The computer can be used to control and sequence the sounds and their characteristics, and also to synthesize any desired wave form. This has made it possible to produce complex electronic music live in the concert hall, without needing to record it on tape first, and even to manipulate the sounds of the various instruments during the performance, as in Boulez's ...explosante fixe.. (1971–73) and George Benjamin's Antara (1985–7).
Electronics and popular music The electronic music of the 1960s, particularly the work of Stockhausen, had a profound influence on many jazz and rock musicians. Miles Davis in particular found inspiration for his jazz/rock fusion, and paved the way for future developments in the field. Groups such as Weather Report incorporated electronic instruments into their ensembles, and the expressive capabilities of the synthesizer were particularly suited to the style that had evolved from free jazz. In the world of rock and pop, more electronic instruments were being played from the early 1960s. At the more popular end of the spectrum, the Beach Boys used an ondes martenot in their hit ‘Good Vibrations’ (1966), while more progressive bands such as Emerson, Lake and Palmer, and Pink Floyd explored the possibilities of the newly invented Moog synthesizer. The use of electronically generated music continued throughout the 1970s and 1980s, especially in dance music, where in some cases it totally replaced conventional guitars and drums. For some rock musicians, notably Frank Zappa, the use of electronic instruments helped to bridge the gap between rock and ‘serious’ music; this trend has continued through to the present in the work of composers such as Brian Eno. From the 1990s the ubiquity of personal computers with advanced production software further expanded the realms of music making.