RSF • Kobol Expander
The French RSF Kobol is a much more compact instrument following their Modular Model 11. It is a monophonic analog synthesizer with traditional controls, knobs, switches and 2 oscillators for a good solid analog synth sound. It came in either a 3-unit rackmount model (pictured above) or as a Mini-Keyboard model. The rackmount version is patchable similar to other semi-modulars from the ARP 2600 to the Korg MS-20. Lots of knobs allow you to control the ADS envelope, the filter section and the nice LFO. (Note that the keyboard model is not patchable.) The oscillator waveforms can be swept across for a very cool morph from square to saw to pulse, etc... This as well as note on/off and other parameters can be controlled via cv/gate. External sounds can be processed through the Kobol filter and envelope sections too. As cool as these beasts may be, however, they are rare finds and somewhat pricey. It has been used by Vince Clarke and Vangelis.
controlled with a MDB poly sequencer.
The Kobol Expander I was introduced in 1979.