[sdiy] Fet to short pedal input?

[Pete Hartman]

Am I just missing something here? If neither the Source nor the Drain is
tied to anything resembling a fixed voltage, then what does the Gate have
to "compare" to (yes I'm being imprecise about the mechanism of a FET).

When one side is a ground, certainly, that makes sense to use a FET for
muting or even a BJT for switching (I've done the same).  But FETs floating
in the air ... unless there's a DC offset in that signal going to the
portamento circuit that can be relied on, I don't see how that would work.

On Fri, Nov 28, 2025 at 3:26 PM brianw <brianw at audiobanshee.com> wrote:

> 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.
>
>
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