Using same pot for two different circuits?

[syzygy]

Will it work to use the same pot (as in a volume knob) to control the volume of two different tone circuits, where one circuit is used at any given time and is selected by a DPDT switch?  Take for instance the ROG Double D that has two gain knobs and two level knobs, each pair for each circuit.  I'm thinking this is only a convenience to switch back and forth without having to adjust levels for that particular circuit.

I'm thinking of the possibility of cramming two tone circuits in the same box and using the volume and gain knobs for double duty instead of putting twice the pots and knobs in the box.  I won't ever be using the effects separately, so I'm not considering having two different enclosures for the circuits.

[petemoore]

You can't have the outputs connected o
 If you could show a schematic somehow, with the circuits as blocks, it would be easier to look over the wiring plan you intend to use,
 Also they cant' be both used in series.
 If I were doing it, I'd DPDT TBypass each circuit, because I don't know the waters around using less switching to do the 'one or the other' trick.
 Is 'one or the other' switching what you had in mind?
 The Gain Pot to circuit [if used as a two lead VR on both] could be SPDT'd to one or the other using one side of a DPDT Switch .. the other side of the DPDT would SPDT the volume knob input from one of the circuit outputs at a time.
 It may be possible to simply wire the gain pot to both circuits?...the test for that is as easy as using a testclip wire to bridge the gain pot to where it connects on both circuits.
 The pots would need to be wired in the same configuration [either 2 connection or 3] without further study...and of course would need to be the same same values for optimal performance....of course you could add a little 'first floor' resistance using a fixed resistor series, between pot and circuit [on 1 circuit] for gain knob value tweek
 ...excuse If I'm typing in confusion...I can't tell if you want the whole thing bypassable or what..

[phillip]

You could use a dual pot, which is two pots that are both controlled by the same shaft.

Another option would be a dual concentric pot, which is also two pots, and each of the two pots can be controlled seperately.  I think the Fender J-Bass (?) used/uses dual concentric pots.  You might have trouble finding a dual concentric pot in the right value.

Phillip

[80k]

yep, dual pots is the way to go.  i know people who have put two identical fuzz circuits together, and control them both at the same time with dual pots, sending them to two different amps.  The slight variation in the circuitry gives it somewhat of a "stereo" sound.

[ninoman123]

Only the active J bass has the dual pots like that.  Sorry to point out the little technicalities. lol

[syzygy]

petemoore,

Thanks for the insight, that should be enough info for me to go further.  I am thinking about a one-or-the-other type switch, and I do have true bypass in mind.  And I would only do this for a pot function that has the same resistance and taper among both circuits.  For example, if circuit 1 calls for a 100k linear pot, and circuit 2 calls for the same, and they are both used for Volume, then that is what I'm thinking about for double duty.  I could try to put together a diagram like you asked.

The dual pot idea sounds cool, but I'm only considering a use of regular pots.

[phillip]

Only the active J bass has the dual pots like that.  Sorry to point out the little technicalities. lol

I knew it was one of the J-Basses...just wasn't sure which one  No wonder the Fender knobs for the dual concentric pots are so freakishly expensive!

Phillip