In our latest build we take on the Fonitronik Ps3100 Triple Vactrol Resonator – A clone of the lovely triple resonator from the rare 1977 Korg Ps3100 polyphonic modular.

What we have here is basically a module combining three bandpass filters (vactrol based filter core from the PS3100) with a simple resettable LFO and some clever CV and signal routing.  The LFO is normalized to the common CV input, which is normalized to the 3 single CV inputs. the 3rd CV channel can be inverted.