Stereo wiring question

[Bearer]

Kind of a complex question that I know I should know the answer to, but I'd like to ask you guys here just to be sure. If I have a stereo output jack with two separate channels (R, L, and ground) and I wanted to add a third signal from an independent volume pot to both channels, could I solder two leads from the volume pot onto the the L and R posts of the jack without fear of mixing the two signals?

[cc9cii]

not without a buffer, which almost always would be an active circuit

[Vizcaster]

Sorry but I have no idea what you mean by a "third signal from an independent volume pot." Is it a dual-ganged pot? Are you looking for a master volume knob that will control the independent stereo channels? Are you looking for a way to use a mono cord when you're not running to two amps?

And if you blend the two stereo channels, are you sure that the pickups are in phase and can behave together without going to separate amp channels? Some stereo wired Gibson ES guitars had the humbuckers out of phase with each other because it was assumed they'd be plugged into the two channels of amps like Fender "normal" and "trem" which were out of phase at the amp. You could not just wire the jack mono or use a Y cord with those.

[Bearer]

My wiring scheme is kind of a complicated one that will ultimately have a stereo and mono mode through one stereo output jack. This is a short outline of what I have:

The neck and bridge pups go to a 4P3T switch that changes between these three settings:
-Stereo Reversed (bridge goes out to left, neck goes out to right; mono channel is off)
-Stereo Standard (Neck goes out to left, bridge goes out to right; mono channel is off)
-Mono (pickup signals are sent to standard tele switch; right channel is off)

The mono and left channel go to one layer of a dual layer "blend" pot wired to control both channel's volume independently of each other, and the right channel goes to another. The left and mono signal goes to the L channel on the jack, and the right to the R.
The middle pickup is hooked up to its own volume pot, and what I figured out is that I'm just going to have that go straight to the mono/left channel on the output jack. Should be fine that way as I'm not loosing any tone options really, and I shouldn't have any risk of contaminating the other signals.

[Bearer]

So, I drew up a schematic for what I want to be able to do, and I'm pretty sure I got it all right. Special things of note, the bridge humbucker is wired to a push/pull pot so that when the pot is down, the PAF is wired in parallel, and when up it's in series. Also, that large block in the middle is a 4P3T on-on-on switch. Hopefully this scheme will be usefull to anyone looking do do some stereo wiring (that is to say if I didn't do something horribly wrong here!)

btw: Here's a few dual gang 500K Audio taper pots I found. Should work wonders since it's not like the one stewmac sells which is more of a blend pot. This is like a concentric pot system with only one shaft controlling the two:
split shaft knurled: http://www.allelectronics.com/make-a...METER/-/1.html
solid shaft: http://www.mouser.com/ProductDetail/...k9KDRfNQ%3d%3d

[cc9cii]

Don't quite see why you have the vol pot wired that way, it's not as if you have a position where both channels are on & have to 'blend' between them.

I think your new idea of using a 'dual' pot is better (still need to change the wiring).

[Bearer]

Yes, I realized that after I posted it, haha. However, now it looks as though everything is solid. Next step, I'll have to get myself a cheapo pawnshop strat and experiment with it, maybe get some sound clips up.

[Wally]

Originally Posted by Vizcaster

Sorry but I have no idea what you mean by a "third signal from an independent volume pot." Is it a dual-ganged pot? Are you looking for a master volume knob that will control the independent stereo channels? Are you looking for a way to use a mono cord when you're not running to two amps?

And if you blend the two stereo channels, are you sure that the pickups are in phase and can behave together without going to separate amp channels? Some stereo wired Gibson ES guitars had the humbuckers out of phase with each other because it was assumed they'd be plugged into the two channels of amps like Fender "normal" and "trem" which were out of phase at the amp. You could not just wire the jack mono or use a Y cord with those.

Vizcaster, I can't speak directly to why Gibson put the pups out-of-phase on the STereo varitone 345's and 355's; but I would guess that it had nothing to do with any Fender amp.....since there were no Fender REverb amps with out-of-phase channels built when Gibson started doing this. Gibson probably had little interest in any Fender amp of the day. They were busy building stereo amps that would fit the bill for these stereo guitars.
I would think it is more likely that Gibson was trying to get that sound on purpose. Some people actually like the out-of-phase thing. The out-of-phase pickup arrangement allows for soemthing other than that big,thick humbucker sound.

[Bearer]

Alright, well, I fixed the diagram a little bit. I moved the dual volume bot to before the switch. This cleans up the whole rig a bit making it more organized; less wires crisscrossing everywhere. Also labeled the humbucker's coils as well as fixed the grounds on the volume pot.

[Vizcaster]

Good point, Wally. I hadn't thought of the timing of the guitars vs. those particular amps but they're what comes to mind when thinking of early two-channel affairs. Let me ask you this, (especially since I'm completely lost on what the OP is trying to do - I'd say he's better off with a couple of volume pedals and a pedalboard mixer or buffer): what amps were people using with early stereo Gibsons? My Gruhn's talks about stereo ES355TD introduced as early as 1959.