CV from expression pedal but via TRS cables

Great question! You’re correct in your assumptions regarding the 5-CV pedal.

However, a normal guitar expression pedal is usually just a potentiometer with a foot pedal instead of a knob. So it works like a passive attenuator. An effect pedal sends a CV signal to the expression pedal via the ring and receives the attenuated signal via the tip of the TRS jack cable.

Here’s a picture:


Source: expressionpedals.com/how-expression-pedals-work

This means that you don’t need to buy an expensive, active CV pedal. You can buy the cheapest passive expression pedal you can find! Simply send it a static 5V signal* from the AE Modular on the ring connection and return the output signal into the modular synth and use it in your patch. The 4I/O module supports TRS jacks, so you will only need one 3.5mm TRS to 6.3mm TRS cable between the AE Modular and the expression pedal. If you use the Master I/O module, you can use the two CTRL sockets with a dual 3.5mm TS to 6.3mm TRS Y cable.

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* ... or any other signal, like an LFO or VCO signal.

Yes, try it out and report back You should also be able to reverse the pedal direction by sending 5V (or something else) to the tip and receiving the ring.

Nice! Well done