BEHRINGER 921A OSCILLATOR DRIVER. Analog Oscillator Driver module for Eurorack. It has a knob for frequency control with the possibility of adjusting the range of octaves or semitones, selectable through the dedicated switch, and a Rectangular Wave Width knob to adjust the amplitude of the rectangular wave. It has 2 combined CV inputs for frequency control, 2 combined CV inputs for PWM and
2 control outputs.