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 origins of musique concrète in the late 1940s. Unlike acoustic or electroacoustic musical works that are realized from scores, 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, sound which is heard but not seen, 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, or sounds employing audio signal processing, 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, digital audio workstations, or analog means such as tape recorders or turntables. 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 what Edgard Varèse termed "sound organisation". According to certain historical accounts, the origin of the term acousmatic can be traced back to Pythagoras; the philosopher is believed to have tutored his students from behind a screen so as not to let his presence distract them from the content of his lectures. Under these conditions, the listener focuses on the sounds being produced to heighten the sense of hearing. In 1955, Jérôme Peignot and Pierre Schaeffer were the first to use the term acousmatique to define the listening experience of musique concrète.