The OB-1 features two voltage-controlled oscillators (VCOs), each selectable between either "Pulse Type" or "Saw Type" waveform, with continuously-variable control ranging from a square wave to a narrow pulse wave for the "Pulse Type" setting, or from a triangle wave to a sawtooth wave for the "Saw Type". The oscillators can be synced, and there is an available square wave sub-oscillator. The voltage-controlled filter is switchable between either 2- or 4-pole, with frequency cutoff and resonance controls. There are two ADSR envelopes: one for the filter, the other for the voltage-controlled amplifier. There are eight program memory buttons for storing and recalling the OB-1's settings. There is a portamento knob allowing for adjustment of portamento amount, as well as a pitch bend/modulation lever.