The BF-22 VCF is a dual Hi/Low-pass filter inspired by the Sallen-Key filter from the early MS-20.

DISCLAIMER: This filter brings to your modular system the character of early MS-20 sound: Kick-ass-rocking-dirty screams! It inherited not only it’s amazing sound, also MS-20 noise floor. If noise floor is an issue for you, this might not be your filter.


  • Dual-channel Sallen-Key Filter. Inspired by the early MS-20
  • High and Lowpass operation.
  • Two CV inputs per channel with a dedicated atenuverter for the first one.
  • CV controlled resonance.
  • The first channel can be linked to the second one with the “Link” switch.


  • Current needs: +12V: 40mA, -12V: 20mA
  • Width: 17 HP
  • Depth: 30mm (including power connector)
  • Aluminiun, heat-treated front panel
  • Designed, kits prepared and completed modules assembled in Barcelona.


*This iBOM is meant to be used together with Befaco’s Assembly guide.