BMC034 - Switched Resistor VCF | Barton Musical Circuits

This is a voltage controlled filter module which utilizes analog switches to adjust the frequency of the filter. The module features two state-variable filter sections which share a common frequency control, these can be used in series for heavier filtering or in parallel to work with stereo sound sources.  It has the following controls and I/O:

Knobs

• Frequency – Controls the frequency of both filters.
• Frequency Modulation – Attenuates a modulating cv input for the frequency control.
• Resonance 1 – Controls the amount of emphasis on the selected frequency of the filter for channel 1.
• Resonance 2 – Same, but for channel 2.

Inputs

• Clock – An oscillator should be input here, it will be used as the clock for the analog switches in the circuit. Pulse waveforms should not be used.
• CV – This is the input for the frequency modulation CV.
• Input 1 – Signal input for channel 1
• Input 2 – Signal input for channel 2

Outputs

• Low pass 1
• Band pass 1
• High pass 1
• Low pass 2
• Band pass 2
• High pass 2

The board features PC mounted pots for less wiring, and mounting holes for flexibility in panel layout. There are Eurorack and MOTM power connectors.