Engineer and artist Michael Callahan was the technical director of the San Francisco Music Tape Center from 1961 to 1964, an early electronic studio whose purpose was to explore audio tape as a creative medium. There he assisted in the realization of works by Morton Subotnick, Pauline Oliveros, Steve Reich, Ramon Sender, David Tudor, John Cage, and the dancer Anna Halprin. While at the Tape Center he performed in the recorded reading of John Cage’s Atlas Eclipticalis. In 1964 he recorded On the Seventh Day Petals Fell in Petaluma for Harry Partch. In addition to co-founding USCO, Callahan was president of Maverick Systems Inc. from 1966 to 1969, manufacturing specialized electronic equipment for media presentations, including the design and installation of the media system for the World discotheque whose proceeds supported the work of USCO. After moving to Cambridge, Mass., in 1968, Callahan became the technical director of Intermedia Systems Corporation, a company that produced multimedia presentations for government agencies, schools, museums, and corporate clients. Subsequently he provided consulting services to museums and institutions on incorporating media in their exhibits and programs. In 1989 he and his wife Adrienne Callahan founded Museum Technology Source Inc., a manufacturer and distributor of audio-visual equipment, primarily to museums. Callahan held the position of supervisor of film studios and electrical engineer at the Carpenter Center for the Visual Arts, Harvard University, from 1977 to 1994.
