i-o47

I-ō47 Multimode Resonator/Filter draws its circuit design inspiration from the classic 1047 module of the ARP2500 system.

Built upon the classic circuit architecture of the original, the design was refined with extensive experimentation using modern components alongside classic configurations of discrete parts.

Specifications
Centre frequency range 16Hz to 16KHz
1V/octave, Coarse and Fine frequency controls
FM input with attenuverter
Low pass 12 dB/octave
High pass 12 dB/octave
Band pass 6 – 12 dB/octave dependent on Q
Notch with variable offset –/+ 2 octaves
Input with gain control
Inverted input with resonance dependent gain
Strike input for pinging the filter
Limiter based on tanh wave shaper which affects primary input (post gain fader)