Acousmatic music

Acousmatic music (from Greek ἄκουσμα akousma, "a thing heard") is a form of electroacoustic music that is specifically composed for presentation using speakers, as opposed to a live performance. It stems from a compositional tradition that dates back to the introduction of musique concrète (a form of musique expérimentale) in the late 1940s. Unlike musical works that are realised using sheet music exclusively, compositions that are purely acousmatic (in listening terms) often exist solely as fixed media audio recordings.

The compositional practice of acousmatic music features acousmatic sound as a central musical aspect. Other aspects traditionally thought of as 'musical' such as melody, harmony, rhythm, metre may be present but more often consideration is given to sound-based characteristics such as timbre and spectrum. Compositional materials can include sounds derived from musical instruments, voice, electronically generated sound, audio that has been manipulated using various effect processors, as well as general sound effects and field recordings.

The music is produced with the aid of various music technologies, such as digital recorders, digital signal processing tools and digital audio workstations. Using such technology various sound materials can be combined, juxtaposed, and transformed in any conceivable manner. In this context the compositional method can be seen as a process of sound organisation: a term first used by the French composer Edgard Varèse.

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