Maryanne Amacher (1938-2009) was an American composer and installation artist. Her work was related to the psychoacoustic phenomenon known as the distortion product otoacoustic emissions. This phenomenon relates to the sounds generated inside the ear that are clearly audible.
Amacher studied composition privately with Karlheinz Stockhausen and at the University of Pennsylvania with George Rochberg. In 1974–80 she collaborated with choreographer Merc Cunningham, composing music for the dance Torse, and in 1975–84 with composer John Cage, for whom she created the soundtrack to his multimedial Lecture on the Weather (1975). She was best known for the City-Links #1-22 series (started in 1967), Music for Sound-Joined Rooms (started in 1980) and the Mini-Sound series (started in 1985). In her last teaching position, Amacher taught electronic music (2000–09) at Bard College in Annandale-on-Hudson, New York.
Maryanne Amacher has worked on psychoacoustic phenomena called the "distortion product otoacoustic emissions". The sounds that result from these phenomena have a long history in music theory and scientific research. In music, they are most often known as "combination tones", "difference tones" and sometimes "Tartini tones" (after the violinist Giuseppe Tartini, who is credited with their discovery). Amacher herself called them "ear tones" until 1992, when she discovered the works of David T. Kemp and Thomas Gold and began to call them with the psychoacoustic terminology: "otoacoustic emission."
These sounds, which appear in a response to the two tones occurring simultaneously in the ear, seem to be located in or around the head, as if there was a "tiny loudspeaker" inside the ear. Amacher was the first to systematically study the use of these phenomena in music using electroacoustic sound technologies. The subtitle of her album Sound Characters (Making the Third Ear) refers to them.