Momentary Bypass Concept- No Modding Required

[mattthegamer463]

Hello folks,

So I came up with this idea today, to build a momentary bypass switch which connects in parallel with your desired effect, so that you can momentarily true-bypass it without turning it off, and much quicker than a on/off footswitch can do.  It uses a relay to switch the signal path.  I figured this would be good for quickly bypassing tube pedals which you would not want to be slamming on and off frequently.



(click for largeness)

Quite simple as you can hopefully see, my only concern with the idea is that there will be clicking produced by the relay contacts.  I'm sure theres a way around that though.  Also the real-world audible noise from the relay would be annoying.

Just thought I'd share this idea, I've never seen anything like this, and my googling turned up nothing.

[PRR]

You only need one relay, a DPDT.

Not sure how it is "quicker".

[mattthegamer463]

My schematic was representing each side of  DPDT relay.

Think of it like this:

Normal pedal ON-OFF-ON motions: Foot down + Foot up to turn off, Foot down + Foot up to turn back on

Momentary Bypass: Foot down and hold to turn off (bypass), Foot up to turn back on

Half the motions, more flexibility, less thinking.

[Processaurus]

Ah, it is a momentary true bypass loop.

A relay might indeed bounce less then a mechanical switch.  It is too bad they don't make mercury wetted relays anymore, as they have zero bounce.

A JFET bypass could be made to be clickless.  Mechanical switches (including relays) would always click, even if they didn't bounce, because of the sudden transition between two voltages (the two signals).

Mesa Boogie I believe uses photo resistors to do the channel+effect switching on some of their amplifiers.  That's pretty serious about not clicking!  A photoresistor would also be the most hi-fi (as well as expensive and fiddly) solid state switching element, if you could get it really off, to avoid bleed.  A shunt series arrangement could get it off, if you used two photocells in series, and a jfet to ground at their junction, to short them out when the cells are dark and kill any signal leaking through.

For stutter pedals JFET's with a couple ms slowdown (see Boss's bypass system, if that sounds interesting) could work out well, without going overboard.