A polyphonic analog synthesizer with a 61-note keyboard. Produced from 1979 to late 1980.

Three versions of the OB-X exist, with 4-, 6- and 8-voice polyphony. The circuitry is based on Oberheim's old SEM design.
The OB-X features two VCOs per each voice, with sawtooth and variable pulse waveforms. A resonant 2-pole (12dB/octave) low-pass VCF is available as the filter, with its own ADSR envelope generator and 3 keyboard tracking modes.
The VCA also offers a traditional ADSR EG. There is a single sine wave LFO, which can modulate the oscillators, filter plus pulse width (which can't be ajusted manually).

32 user programmable patches can be stored in the unit's battery-backed internal memory. Other features include polyphonic sample/hold & portamento, cross-modulation plus a CV/gate interface for external control (with third party MIDI retrofit kits available).
Some sources state the OB-X also features a ring modulator and a cassette interface, but I'm unable to verify this. If you have any concrete information, please /msg me.

Famous users include Depeche Mode, Tangerine Dream, Philip Glass, Jean-Michel Jarre, Chick Corea, Queen and Mike Oldfield.

Dimensions/Weight
105(w) x 57(d) x 18(h) cm
20 kg


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