While waiting for the IC40106 to arrive for building multi VCOs and other signal generators, I’ve build a passive linear-attenuator fitted in 7HP 3U size module as following specifications:
7HP 3U (slightly wider HP to provide some space for my fingers to twist the knobs, perhaps I can swap with much smaller knob caps).
It has 4 inputs/ outputs 3.5mm mono audio jack with linear attenuator. Each i/o is controlled with 100K ohm linear potentiometer to attenuate CV signals or audio (if unavoidable). Ideally, for audio signal, I will design another attenuator module using audio pot (non-linear/ logarithmic).
100K ohm potentiometer value was used to handle any high impedance inputs.
What we can do with this! Ratio turns with various configs!