Sound diffusion (sometimes referred to simply as 'diffusion') is a performance practice in the field of

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 tradit ...

. According to composer and theorist

Denis Smalley Denis Arthur Smalley (born 1946 in Nelson, New Zealand) is a composer of electroacoustic music, with a special interest in acousmatic music. Biography Denis Smalley studied at the University of Canterbury and Victoria University in his native New ...

, it describes the "projection and the spreading of sound in an acoustic space for a group of listeners" during a concert. These concerts can be seen as acoustic recitals without performers, where sound is exclusively generated by loudspeakers. In many cases, the sound diffusion is performed by the composer themselves, whose task it is to integrate and interpret the music within the concert space. The practice was originally formulated by composer

Pierre Henry Henry at his home (January 2008) Pierre Georges Albert François Henry (; 9 December 1927 – 5 July 2017) was a French composer known for his significant contributions to musique concrète. Biography Henry was born in Paris, France, and bega ...

and based on the diffusion of a stereo signal to multiple loudspeakers using a special mixing desk. Differing from the spatial sound approach adopted by

Stockhausen Karlheinz Stockhausen (; 22 August 1928 – 5 December 2007) was a German composer, widely acknowledged by critics as one of the most important but also controversial composers of the 20th and early 21st centuries. He is known for his groun ...

and others, the loudspeaker orchestra consisted of a diverse range of speakers, specifically chosen for their diverse tonal characteristics. The aim of the diffusion is to “exaggerate the dynamic, spectral and spatial content of the musical material already present in the work.” The technical limitations of magnetic tape (such as tape noise or limited spectral range) required the intervention of an engineer in the systems’ early history. These technical considerations would eventually include the diffusion process. The first formalized system based on this approach was the

Acousmonium The Acousmonium is the sound diffusion system designed in 1974 by Francois Bayle and used originally by the Groupe de Recherches Musicales at the Maison de Radio France. It consists of 80 loudspeakers of differing size and shape, and was design ...

of the

Groupe de Recherches Musicales A group is a military unit or a military formation that is most often associated with military aviation. Air and aviation groups The terms group and wing differ significantly from one country to another, as well as between different branches ...

(GRM), the collective founded by

Pierre Schaeffer Pierre Henri Marie Schaeffer (English pronunciation: , ; 14 August 1910 – 19 August 1995) was a French composer, writer, broadcaster, engineer, musicologist, acoustician and founder of Groupe de Recherche de Musique Concrète (GRMC). His inno ...

and Pierre Henry in 1958. Modern diffusion practice also tries to articulate musical material by playing different passages through different sounding pairs of speakers. Composers generally do not provide a score or notation that determines how the diffusion should be done precisely. It is up to the diffusion engineer to perform the piece in such a way that the musical content is adequately interpreted as well as adjusted to the specific loudspeaker arrangement and acoustics of the respective concert hall.{{cite book , last1=Bates , first1=Enda , title=The Composition and Performance of Spatial Music , date=2009 , publisher=Trinity College , location=Dublin

References

Electronic music

See also

References