'Ivo' is a resonant low-pass VCF (Voltage Controlled Filter), switchable between 2-pole (12dB/octave) and 3-pole (18dB/octave) responses, with voltage control over feedback (resonance) as well as cutoff frequency. It will self-oscillate in 2-pole mode.

The module has two audio inputs, one with an attenuator, so it will also mix two signals at the filter input.

The module is 100% analogue, using discrete transistor OTAs.