BF-22

A dual high-pass / low-pass filter in 17 HP, inspired by the Sallen-Key filter of the early MS-20, with its screaming resonance and its noise floor too.

Key features

• Two independent filters, each switched between high-pass and low-pass (HP / LP)
• Manual CUT OFF and resonance on each channel, resonance under CV control
• Two cut-off CV inputs per channel, the first through an attenuverter (X-1 to X1, zero at noon), the second with V/Oct tracking
• VOL knob on each input: turn it up to just before the LEDs flash for the most resonance with the least noise
• LINK switch sends the output of filter A into the input of filter B, for MS-20-style HP into LP