3pdt power switching to avoid noise in the signal path (Heliotrope)

[Gabriel]

Dear all,

I  build de design of the Heliotrope. Works very nice to be a Noisy-ish pedal.

The situation to resolve is: when bypassed, it still makes a sounding whine-noise on the circuit (from the sample rate). I don´t know how can this be possible...I also tried also the "grounding input" technique, with no positive result.

I heard other reports of this circuit with the same problem of getting this whine on the signal path..

So i had to configure the 3pdt to power on/off. I really need to have a clean bypassed signal.

The question is: how to do a power on/off switching? closing the positive or the ground? any suggestion?

The best to all.

[Morocotopo]

Gabriel, I don´t know this schematic, but switching power is a bad idea. You will get a really loud POP! every time you switch...

[Gabriel]

Thanks for the suggestion.

I build the sabro tone version.

As you may know, this is a effect that will be bypassed 90 % of the time.  So, the osc/whine in not welcome when bypassed..

The best to you.

[jmasciswannabe]

If I recall correctly I made mine where the 3pdt established ground to pin 4 on IC1 at the same time it grounds the LED to show pedal is on. I believe this is a primitive way of doing things and can potentially damage the chip, but hey it works and no bleed and over a year later no issues.

[Gabriel]

Hey! thanks, i will try that.

[Gabriel]

Thanks jmasciswannabe!

I found a way more "friendly": grounding the lug 2-3 of the sample rate, that cancel the whine on bypass.

Vibes!

Gabriel.

[mthibeau]

Thanks for that tip, my Heliotrope clone has been in a bin due the horrible bypass whine.

[jmasciswannabe]

Yeah, that does sound like a better plan. Will try it out myself!