Available as an assembled Module and as a DIY project.
This Module is currently available.
OTA 4-Pole Filter
At its core this is the CA3080 OTA based filter that was in the original RevA version of the Octave Cat, before they switched to the SSM2040. It has been adjusted for modular level and the expo-converter uses super-matched 3906’s and temperature compensated for upwards of 5-octave tracking.
Additionally, there is a 4-pole output as well as a 1-pole output. These outputs are inverted from each other, so they can be mixed together for Bandpass.
These merchants probably sell this module. Huh?