[sdiy] Fet to short pedal input?

[brianw]

A relay will certainly have the conductive properties of the pedal switch.

My questions are 1) how fast will the relay open circuit after the Frostwave converts MIDI velocity to voltage? and 2) how many notes can you play before the relay wears out?

If the relay doesn't 'release' quickly enough, then the portamento won't work as expected, since the early part of the note will jump instantly towards the new pitch CV. In other words, the timing between the Note On gate (when the pitch CV changes) and the relay disengaging has to be zero (or less!). One possible solution is to delay the Gate - perhaps using the Frostwave as the gate source.

Brian


On Nov 28, 2025, at 7:39 AM, Michael E Caloroso wrote:
> You really need a control element with infinite resistance (open circuit).  That element needs to have open circuit and short circuit states and it's hard to beat a relay controlled by a Darlington BJT.