Available as an assembled Module and as a DIY project.
This Module is currently available.
Multimode VCF
The CubuSynth VCFA is a multimode VCF with LP,HP and BP modes with integrated VCA,
CV control over Frequency, Resonance and Volume. The CV input for the Frequency
features 1V/Oct scaling over about 2~3 octaves. So you can even create plucky melodies
with the resonance in "ringing" mode.
The Gain control can reach a nice, soft saturation.