VOLTAGE CONTROL and the
Voltage control may be defined as the use of electrical voltages to determine the instantaneous values of musical parameters. The concept was introduced to the electronic music studio in 1963 (at the San Francisco Tape Music Center) and was instrumental in making electronic music composition a real-time process (instead of a tedious tape-splicing exercise).
Voltage control has been generally applied to only two variables -- pitch and amplitude. And the sources of control voltages have been limited to relatively simple function generators, subsonic audio sources, and monophonic, dynamically unresponsive organ keyboards.
The Electric Music Box extends voltage control to virtually every musical dimension. The system enables voltage control of pitch, amplitude, waveshape, filter parameters, envelope characteristics, modulation, reverberation, and quadraphonic location.
Complementing this diversity of voltage-controlled parameters is a variety of control voltage sources. Touch-sensitive and electro-mechanical keyboards respond to the dynamics of playing; sequencers and envelope generators produce complex transient or cyclic patters. External signals interact through envelope and pitch detectors; the element of uncertainty is introduced by two specialized random voltage sources.
In the Electric Music Box, a consistent distinction is maintained between control voltages (which define musical structure) and signals (the raw material of electronic music). This treatment of control voltage as an important, separate entity contributes significantly to the conceptual clarity and excellent technical performance that characterize the Electric Music Box