Conceived as an affordable flexible semi-modular synthesizer in miniature, the VCS3 (Voltage Controlled Studio, version #3) was the first portable synthesiser offered on the open market, beating the Minimoog by a year. Like the VCS1, the VCS3 could process external sounds as well as generate them internally. Designer Zinovieff, a geologist, applied a scientist's analytical bent to his interest in electronic music. The ‘Pin Panel Matrix’ for patching is one of the VCS3’s most distinctive features. Tristram Cary designed the instrument in the new ‘L-shape’, so that the machine could be used at a desk as a teaching machine, and for demonstrations, as well as composition. There was no keyboard, but there was a joystick, adapted from the radio-control mechanism of a model aircraft. It also included an integral amplifier, stereo speakers, and stereo inputs.
The principal difference between the Mk I and the later issue Mk II was that the Mk I allowed individual patching of each VCO waveform on the matrix board, whereas the Mk II dispensed with this and allowed for more input/output routings.