French composer, acoustician, and electronics engineer who in 1948, with his staff at Radio-diffusion et Télévision Française, introduced musique concrète in which sounds of natural origin, animate and inanimate, are recorded and manipulated so that the original sounds are distorted and combined in a musical fashion. The means of manipulation include changing the speed of the playback to alter pitch, playing the tape backward, cutting the tape so as to exercise precise control over duration, filtering out or reinforcing certain sound-wave frequencies, and other more complex manipulation. Schaeffer's 10-movement Symphonie pour un homme seul (1950; “Symphony for One Man Only”), produced in collaboration with Pierre Henry, was the first major concrete piece. This and other works of musique concrète reflect an approach to sound that had an important influence on composers of aleatory (aleatory music), or chance, music. His other works include the experimental opera Orpheé 53 (1953).

Schaeffer taught electronic composition at the Paris Conservatory from 1968 until 1980. His writings include novels, short stories, and essays, as well as theoretical works in music, such as À la recherche d'une musique concrète (1952; “In Search of a Concrete Music”), Traité des objets musicaux (1966; “Treatise on Musical Objects”), and the two-volume Machines à communiquer (1970–72; “Machines for Communicating”).