CLOUD MUSIC (Hybrid Audio/Video Installation), 1974-1979 Robert Watts, David Behrman & Bob Diamond

CLOUD MUSIC is an installation developed collaboratively during the years 1974 to 1979. It consists of a video camera (black & white 1974-78, color thereafter), which scans the sky; a video analyzer, which sense the changes in light produced by passing clouds; and a home-made electronic sound synthesizer, which responds musically to the passage of clouds overhead. For this historical exhibition a black and white camera is being used. 1977 The Annual, San Francisco Art Institute at Fort Mason 1981 New Music America '81 Festival, San Francisco

CLOUD MUSIC

Video camera (A) points at the sky. Specially designed video analyzer (B) superimposes six electronically generated crosshairs upon the video image. Each cross hair may be positioned anywhere.

Composite image (sky plus crosshairs) is sent to the video monitors (C). The video analyzer generates six control voltages. Each voltage is proportional to the instantaneous light value at the point where one of the crosshairs is positioned. As cloud surfaces pass these six crosshair points, the voltages vary in response to the clouds' light content.

Digital electronic music system (D) receives the six voltage outputs from the video analyzer. The music system senses voltage changes made by the analyzer and converts the changes into harmonic progressions and dynamic shifts.

Sound from the music system is sent to a six channel loudspeaker system (E). The loudspeakers surround the viewing space and the video monitors. Cloud Music is intended for installation during times of the year when weather conditions favor a likelihood of high daytime cloud activity. p.152

DAVID BEHRMAN: "For the sound, the outputs from Bob Diamond's video analyzer are used to create an interweaving of slowly shifting, multi-layered harmony that parallels the movement of the clouds. The technical means by which the passing of the clouds can be used to make music around a listener are of the 1970's - because only in the last several years have the sensory, logic, and video circuitry become easily accessible to individuals such as ourselves. But in spirit the project might be close to the old outdoor wind and water driven musical instruments of Southeast Asia and Polynesia.

Sound is produced by eight banks of audio-range function generators, four to a bank, each of which is tuned to a pre-selected four-part "chord" made up of pure modal or microtonal intervals. Six of the banks can each be detuned to four parallel transpositions by an output from the video analyzer. Any harmonic change corresponds to a minute change in light of crosshair in the video image.

Like sailing, the music is weather-dependent." p.153