I have seen the optical hihat controller in the edrum.info web. And I have some doubts.
Is that pedal on/off or is it gradual? As I can see when the pedal is closed the light does not reach the sensor, but when opened it fully reaches the sensor, so, for me, it seems that it is a 2-state pedal. Am I wrong?
I want to build a hihat controller more durable. With a slider resistor it is not very durable. The optical alternative looks good, but only if it allows gradual positions (open - halfopen, halfclosed, closed..)