Voltage Controlled State Variable Filter
The TLN-428 is a state variable filter built around a Curtis Electromusic Specialties CEM 3320 chip. Four simultaneous outputs (all with two pole response) are provided: low pass, high pass, band pass, and notch. A built in mixer allows for two audio inputs. The filter frequency can be set using a panel mounted pot, a "one volt per octave" external control voltage, or via two external FM inputs with attenuators (one reversing). Filter resonance can be set using a panel mounted pot or an external control voltage with a reversing attenuator.
http://www.tellun.com/motm/diy/tln428/TLN-428.html
Module is available as a DIY project only.
This Module is currently available.