Two circuits, only one at a time in one enclosure sharing pots. Dual gang best?

[Locrian99]

Pretty much as the title says.   

I want to put two of my favorite muff circuits in one enclosure, I'll have them switchable with a footswitch which one is on.   Never both on.   Only want one set of pots, jacks, dc plug.   Dual gang pots the best way to do this?  Or?

Thanks

Edit and would there be any issue with using one dpdt for a mids switch (both circuits feed into it, and out of it) it would be switching the 4nf cap in the tone stack).

[ElectricDruid]

You *could* do it with dual gang pots. It ought to work and it's conceptually simple.

If the circuits are similar you could re-use certain elements (input buffer, output stage?) which they share, rather than have to build two. If the circuits are *really* similar, you could switch just the components that change between the two versions.

It'd be possible to use one set of pots and switch them between the two circuits with multigang switches or relays, but it's a clunky solution (probably *literally* clunky too!).

[ThePracticalPeasant]

If the circuits are similar you could re-use certain elements (input buffer, output stage?) which they share, rather than have to build two. If the circuits are *really* similar, you could switch just the components that change between the two versions.

It'd be possible to use one set of pots and switch them between the two circuits with multigang switches or relays, but it's a clunky solution (probably *literally* clunky too!).

I had similar thoughts.

Worst case would be a dozen relays driven from the foot-switch but depending how similar the effects are, it may only require, for example, one relay to switch the tone circuit rather than 3 to switch the pot. That said, if the effects are really similar, it might be possible to switch the "different" part in and out using just a QPDT switch [if you can find one]; effectively switch the power and enough of each circuit such that it doesn't interfere with the other [floating there un-powered]

As for the sound from an array of little low-power relays in a stomp-box enclosure?
I doubt you hear them, and if you do... find a knob marked 'gain' and twist it clockwise.

[Locrian99]

You *could* do it with dual gang pots. It ought to work and it's conceptually simple.

If the circuits are similar you could re-use certain elements (input buffer, output stage?) which they share, rather than have to build two. If the circuits are *really* similar, you could switch just the components that change between the two versions.

It'd be possible to use one set of pots and switch them between the two circuits with multigang switches or relays, but it's a clunky solution (probably *literally* clunky too!).

K the two circuits will have different transistors, possibly one including an op amp instead of the transistors.   Still have some decisions to make on my breadboard side figured just doing two seperate boards which should fit in a 125bb easy enough.  Would be the simplest and most economical way as all those parts are cheap compared to a ton of switches.     Also would want to limit the number of switches some what other than one to make a small change to the tone stacks which will share the one component value of c9 from kitraes muff schems.   Sounds like dual gang will work though just wanted to make sure I was thinking correctly.   Having the signal end up going to both gangs of the tone and volume pots shouldn't matter I am assuming as only one of the volume pot gangs will be connected to the output at a time. 

[Locrian99]

If the circuits are similar you could re-use certain elements (input buffer, output stage?) which they share, rather than have to build two. If the circuits are *really* similar, you could switch just the components that change between the two versions.

It'd be possible to use one set of pots and switch them between the two circuits with multigang switches or relays, but it's a clunky solution (probably *literally* clunky too!).

I had similar thoughts.

Worst case would be a dozen relays driven from the foot-switch but depending how similar the effects are, it may only require, for example, one relay to switch the tone circuit rather than 3 to switch the pot. That said, if the effects are really similar, it might be possible to switch the "different" part in and out using just a QPDT switch [if you can find one]; effectively switch the power and enough of each circuit such that it doesn't interfere with the other [floating there un-powered]

As for the sound from an array of little low-power relays in a stomp-box enclosure?
I doubt you hear them, and if you do... find a knob marked 'gain' and twist it clockwise.

Err sounds like it might be worthwhile to do some research on relays while I'm looking into this. 

[ThePracticalPeasant]

Err sounds like it might be worthwhile to do some research on relays while I'm looking into this. 

The way I envisioned it was to use a relay for each leg of each component that needed to be shared between the effects. Normally open contact to one effect, normally closed to the other. I'd probably start with a relay for each of the hot terminals of the input and output, the input power, and any un-grounded legs on the pots that were in use.

Energize all the the relays together with an on/off switch from the same power supply that runs the fuzz circuits...

Electrically it'd work; though I'm not nearly knowledgeable enough to know if you'd also need to lift the idle circuit's ground or if there are any audio-related limitations or issues with this solution.

[idy]

I hope this guy tries it. It is actually a pretty simple implementation, dual pots, two circuits. Discussing the alternatives just makes it sound smarter. It may seem kind of a silly thing, two versions of a circuit in one box, same knobs, but actually kind of a nice one. Whimsical.

[RickL]

   

[Locrian99]

I hope this guy tries it. It is actually a pretty simple implementation, dual pots, two circuits. Discussing the alternatives just makes it sound smarter. It may seem kind of a silly thing, two versions of a circuit in one box, same knobs, but actually kind of a nice one. Whimsical.

I'm still pretty new to this stuff.   Started building stuff 5-6 months ago.  I've never looked into relays or have any idea how they work etc.   appreciate the suggestions though as now is something I'll need to do some looking into.   I suspect for this project though I'll move forward how I was thinking before.   
The idea of  the multiples of the same circuit is certainly not mine or original.   I was playing around with my friends muffuletta (jhs pedal with 7 I think muff variants in it).  Thought it was pretty cool but after playing around with it for awhile I found myself only ever using two variants on the pedal and ignoring the rest.   I'm sure there are smarter ways of doing it than my idea of the dual gang pots which I wasn't even 100% sure would work.    And I knew I didn't want a whole bunch of switches for different things (see pedal pcb muffin factory).   I figured I could pretty easily fit two of the circuits in a 125b and only take up one spot on my power supply.   That being said I'm also thinking of just doing my favorite muff variant and a rat in one box as I already have the first variant decided on I'm just debating on the second.   And the rat uses the same pot values, would sit in the same spot in the signal chain and don't know why id ever want the muff and rat on at the same time.     Anyways kind of just needed to know I was barking up the right tree on how to implement it and there was some obviously way easier way of doing this.     

[duck_arse]

it wouldn't be the first time this week, but I think I'm missing sometheing here. do you mean to use dual, ganged pots, or dual, concentric pots? if ganged, what is the aim? you set the controls as you like for circuit 1, then select circuit 2 instead, and all the controls are set exacly the same as for circuit 1. so you then need to set all the controls for circuit 2 maximum toan, repeat for each circuit selection.

[GibsonGM]

For reference, this type of relay can come in handy - I bought a dozen or so a few years ago.  They're back-ordered at this point, but maybe there is a similar part thru another supplier:   https://www.mouser.com/ProductDetail/KEMET/EC2-9SNU?qs=BenOyfdfArpFAM5JSz9SHQ%3D%3D

I got dual-coil models...can use 2 footswitches ("A" and "B") to trip them, or rig up a "Boss" fet switching arrangement to do it via flip-flop from 1 switch.  If you ever order, make sure whether you need the one coil or dual coil model...

Not entirely specific to your problem, Locrian - much of what you're talking about might be able to be done with one 3- or 4-pdt stomp.  But since you showed an interest in relays...

[Locrian99]

For reference, this type of relay can come in handy - I bought a dozen or so a few years ago.  They're back-ordered at this point, but maybe there is a similar part thru another supplier:   https://www.mouser.com/ProductDetail/KEMET/EC2-9SNU?qs=BenOyfdfArpFAM5JSz9SHQ%3D%3D

I got dual-coil models...can use 2 footswitches ("A" and "B") to trip them, or rig up a "Boss" fet switching arrangement to do it via flip-flop from 1 switch.  If you ever order, make sure whether you need the one coil or dual coil model...

Not entirely specific to your problem, Locrian - much of what you're talking about might be able to be done with one 3- or 4-pdt stomp.  But since you showed an interest in relays...

Cool, from the little bit I've looked into them seems like these would be something handy for future projects.   

As you said I think my end goal for this really just needs 3 3pdt switches, one for each circuit for true bypass and one from the jacks directing the signal which truebypass switch to go to and provide an led indicator for which circuit is active.   The circuits can share the pot with the dual gang without the signal heading into and out of each other.   As duck arse I think was saying this wouldn't be ideal for switching from one effect to the other in the middle of a song but I don't foresee that being an issue for me. 

[ElectricDruid]

it wouldn't be the first time this week, but I think I'm missing sometheing here. do you mean to use dual, ganged pots, or dual, concentric pots? if ganged, what is the aim? you set the controls as you like for circuit 1, then select circuit 2 instead, and all the controls are set exacly the same as for circuit 1. so you then need to set all the controls for circuit 2 maximum toan, repeat for each circuit selection.

I assumed the idea was to compare the two circuits side-by-side with the same settings, like the ultimate A-B test.

If not, I agree, it makes much more sense to be able to set up the two sounds independently, either with dual concentric pots or simply two sets (wouldn't take up *that* much space with those little 9mm pots with a white line on the shaft).

[Locrian99]

I suppose the 9mm pots would work really my end goal is to combine effects I wouldn't use stacked and would be in the same part of the signal chain into one enclosure to save some space on pedalboard it would be minimal, eliminate some extra cabling and share the power source.    Thought sharing the same pots would be nicer aesthetically but I guess I can see more of the downside the more I think about it.