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Tone knob bypass switch

I'm building a Varitone box and I need to add a switch to bypass the tone pot on the bass. I searched and found this diagram
3396717693_59d9a94d36_o.png


I don't want to buy a push/pull pot because I already have a DPDT on/on/on switch. I don't mind drilling a hole. Is the switch part of the pot the bottom view of a DPDT on/on/on switch?
 
It doesn't matter whether the switch is on the pot or not that's just for convenience.

Now someone who knows more about circuits than I do can correct me if I'm wrong, the way that pot is wired in your picture only bypasses the cap and the entire pot would still be putting a load on the circuit.

That being said, get a DPDT on/on switch and assume the lugs are numbered like this

1 2
3 4
5 6

Now solder the hot wire that runs to your tone pot from your volume to lug 3, then run a wire from lug 1 to your tone pot as usual and then back to lug 2. From here solder lug 4 to where ever you usually send your tones output (usually to your jack), and then either bridge lug 5 and 6 by bending them together or soldering a short length of wire between them.

Now the other way will bypass your cap for sure so that your tone knob does nothing when its turned, but the way I (tried to) describe will totally bypass your entire tone pot and remove the load from the circuit for sure.

I'm no electrician, just a problem solver, so I could be totally wrong but I do think I have the right idea.
 
That will bypass the tone circuit. It lifts the cap connection to ground; without a connection on the ground end, the pot and cap are out of the circuit, and do not load the output.

But yes, the switch in that picture above doesn't have to be a push-pull on the pot. However, DPDT on/on/on may be a little confusing - two of the positions will have the tone pot in, one will not.
 
I drew the diagram you linked.

You can use a DPDT, SPDT or SPST switch instead of a push/pull pot if you want to, just separate the switch from the pot in the diagram. The wiring will be exactly the same

Now someone who knows more about circuits than I do can correct me if I'm wrong, the way that pot is wired in your picture only bypasses the cap and the entire pot would still be putting a load on the circuit.

Nope. That would be true if this were a volume control, but as a tone control, only two terminals of the pot are connected into the circuit, so removing one of them breaks it's connection to the circuit, as the remaining one terminal that is still connected has no path to return to ground.
 
I drew the diagram you linked.

You can use a DPDT, SPDT or SPST switch instead of a push/pull pot if you want to, just separate the switch from the pot in the diagram. The wiring will be exactly the same



Nope. That would be true if this were a volume control, but as a tone control, only two terminals of the pot are connected into the circuit, so removing one of them breaks it's connection to the circuit, as the remaining one terminal that is still connected has no path to return to ground.

thanks. it worked :bassist: