Kilpatrick Audio - K6501 Philter

Behind the Philter is none else than the fantastic multi mode filter from the Phenol synthesizer, adapted for Eurorack. At first glance it looks pretty simple and tame, yet soundwise it is completely massive and big filter which grades up the sound of any "slow coach" VCO.

The Philter's core is a two-pole design with 12dB slope and a special resonance limiter ofr high peaks without oscillation. There are simultaneous outputs for low-pass, band-pass and high-pass with LEDs displaying signal level at each filter type.
The cutoff frequency and resonance are dialed in with potentiometers and in addition there's a FM input with attenuator for modulating the cutoff.