Stereo wiring help

[carter84]

I am looking to wire a nashville tele with 2 p90s and a standard tele bridge. 2 output sockets with vol and tone for each. 3 on/off/on switches to switch between outputs. Can anyone help with a wiring diagram?

[newey]

carter84-

Hello and Welcome to G-Nutz2!

Just so happens that I have a stereo tele project which has been languishing half-built and unfinished for years. In the middle of building it, my real-life work took off and the project got packed up and never finished. I'll have to see if I can find the diagram for mine, but it probably will be dissimilar enough from yours as to not be of much use to you. We'll probably have to work up a custom diagram for what you want to do.

My project (as it was envisioned anyway) also had 2 output jack sockets with two Tele Custom humbuckers, the ones with the 3X3 pole pieces. No lever switch, I just had rotary switch to switch the pickups. One of the two jacks has a switched jack wired so that inserting a cable into just one jack gives both pickups in mono, switchable via the rotary switch. When a cable was plugged into the switched jack, the 2 pickups were split into the 2 stereo channels, the neck pickup to one channel, the bridge to the other. Each pickup had its own volume control, to allow blending of the 2 channels. There was a dual-gang tone pot, one gang for each pickup, so as to keep the channels separate when in stereo. The idea was that the guitar would play "normally", in mono, with a single cable into one amp, but then 2 cables and 2 amps would give stereo.

There is a somewhat longish thread here from about 10 years ago or so where I worked out the plan for this. A lot of the discussion centered on the question of whether it was viable to have the channels share a common ground wire, or whether each channel should have a separate ground. Ultimately, the consensus was that the channels needed to be completely separated; this dictated the type of switched jack I had to use since two separate connections had to be switched.

Before we can zero in on a diagram for you, however, some questions:

with vol and tone for each

Are you going to use concentric pots? Biggest problem with my project was the limited room on a Tele switchplate. I had 4 knobs in a row- a rotary switch, 2 volumes, and a master tone (via dual-gang pot). There would have been no additional real estate on the plate for any other switches. You will need to plan your layout carefully. And bear in mind that components can't be crammed in too closely as the wiring to them takes up room, too- and wires don't do right angles very well.

3 on/off/on switches to switch between outputs

Well, you will have 3 pickups, and two output channels. How are you envisioning this switching to work? The "off" part I got, but what pickups get sent where in stereo? And, is the guitar always in stereo, or is there a "mono mode"?

And, more basically, we should define what you mean by "stereo". Based on your description of 2 P90s and a regular Tele bridge pickup, I have been assuming that your project, like my long-neglected one, would have a pickup (or pickups, plural, since you have 3) going to one channel, and other pickup or pickups going to the other channel.

There is another way to do stereo, by using split-coil pickups, so that one channels carries the signal from the E-A-D strings and the other channel carries the G-B-E. Gretsch Stereo White Falcons were (or still are, for all I know) wired in this fashion. I assume this is not what you intend, since you are not using pickups with that capability.

BTW, you can buy a "blank" Tele switch plate, allowing you to drill your own holes where you want them. That's what I did for my 4-knob project. I have seen mini-toggles mounted on a regular Tele control plate, mounted through the slot for the 3-way lever switch, but I always though that looked too homebuilt. Anyway, though, plan and measur eyour layout carefully. When I laid my project aside, I had it pretty much wired up, but was having trouble getting the wires all tidily routed so that they would fit into the limited Tele control cavity.

[carter84]

Thanks for your reply, the idea was a blank tele control plate drilled for 2 vol and 2 tone pots in line with the switches on the pickguard. If space is tight, then concentric pots would be an option. The P90 pickups would have half the screws removed from each, so the neck pickup would sense the top 3 strings and the middle pickup the other 3. The switches would be wired in series (if possible) like the red special with the switches selecting output 1/off/output 2. If no pickup was switched to output 2, no sound would be heard from that socket.

The thinking behind it was if one pickup just heard the bass strings, It could go to a blue box or similar octave down pedal and either the other p90 or the bridge pickup going to fuzz/distortion, to give a bass playing alongside guitar effect. The same idea as the submarine pickup (www.submarinepickup.com) but using a standard P90.

There wouldn't be a separate mono or stereo mode, if the switches were on output 2 or off and the lead was in output 1, no sound would be heard, and vice versa.

I'm not that worried about it looking too homebuilt as it's just a partscaster made from a cheap neck and body, it's actually a strat body ( so quite a bit of space to play with) with a modified tele pickguard (a bit like the whiteguard strat fender brought out in 2018).

[newey]

OK, so we are talking the Gretsch-style stereo wiring after all, at least for the P90s. I wonder to what extent you will still get output from the P90s on the sides where the pole screws are removed.

the idea was a blank tele control plate drilled for 2 vol and 2 tone pots in line with the switches on the pickguard. If space is tight, then concentric pots would be an option.

Since this is not an actual Telecaster, fitment may or may not be a problem. Measure everything carefully. If 4 pots and some switches have to fit a Tele control plate, though, I doubt that full-sized pots will fit, but the mini-sized ones might fit.

The switches would be wired in series (if possible) like the red special with the switches selecting output 1/off/output 2. If no pickup was switched to output 2, no sound would be heard from that socket.

This adds a wrinkle to things. Without actually drawing anything up, just first blush, 2 pole switches might not be enough to both switch the 2 outputs of a pickup from A to B and also to bypass the "series chain" when that pickup is off. 4-pole switches are available, but have a bigger footprint. I'll have to look a bit closer at that, and maybe someone more saavy than me can weigh in. Pretty sure that On/Off/On switches won't work here, if it's possible with 2-pole switches at all, On-On-On switches will certainly be needed. This is because, in a series set-up, we can't just turn a pickup "off", i.e.' by disconnecting its leads, that "breaks the series chain" of the other pickups and no output is heard.