Here’s the stereo (linked operation) or dual Moog style transistor ladder low pass filter eurorack module from Strange Science Instruments. The F-1 gives you two filters with 2, 3 or 4 pole operation, options to link filters for more extreme filtering (up to 48dB per octave response), formant FX, audio rate modulation is lovely and I also show you how to make a high pass filter out of a low pass filter.
M-4 Mixer demo – https://youtu.be/ulBFjuAGAFg
