Coil splitting. How to change which coil to tap?

[PoPo75]

I recently wired up my Les Paul with a traditional LP set up but I added a 2 push-pull switches on the tone controls. It works but the "inner" coil stays ON and the outer coil turns off. I would like it to be opposite.

When the pickup is split I want the outer coils to be on. Is this possible? I'm using 2 Dimarzio 36th anniversary pickups. I wired them as per the Dimarzio web site with the black and white wires soldered together and going to the push-pull. Red=hot and green/bare=ground.

[big_teee]

I recently wired up my Les Paul with a traditional LP set up but I added a 2 push-pull switches on the tone controls. It works but the "inner" coil stays ON and the outer coil turns off. I would like it to be opposite.

When the pickup is split I want the outer coils to be on. Is this possible? I'm using 2 Dimarzio 36th anniversary pickups. I wired them as per the Dimarzio web site with the black and white wires soldered together and going to the push-pull. Red=hot and green/bare=ground.

Yes it is possible, and I do it often.
All that is required is to take the ground off the push pull switch and wire the output to that location.
You can see how it works on this diagram.
http://www.1728.org/humbckr7.gif
When you apply ground to the leads B & C?
Current flows toward lead A, the north coil.
If you apply output at B & C?
Then you will have Current flowing toward Lead D, the South coil.
You would get the output from the Vol. Pot, where the pickup is connected.
GL,
T

[PoPo75]

Yes it is possible, and I do it often.
All that is required is to take the ground off the push pull switch and wire the output to that location.
You can see how it works on this diagram.
http://www.1728.org/humbckr7.gif
When you apply ground to the leads B & C?
Current flows toward lead A, the north coil.
If you apply output at B & C?
Then you will have Current flowing toward Lead D, the South coil.
You would get the output from the Vol. Pot, where the pickup is connected.
GL,
T

Please forgive me I'm not sure if I am understanding. Currently I have the black and white going to the push/pull.

Are you saying to switch the swap the red and the black?

[big_teee]

Please forgive me I'm not sure if I am understanding. Currently I have the black and white going to the push/pull.

Are you saying to switch the swap the red and the black?

No, you have the pickup wired correctly.
You want to rewire the push-pull.
Take off the ground and replace it with the hot, or output from the Vol. Pot.
On the diagram below, take the ground off the push pull switch and move it to the pot where the pickup is wired.
Your colors will be different but the concept is the same.
Wiring Diagram
**edit
In your case move the black wire from the back of the push-pull, and connect it where the red pickup wire is on the pot.

[PoPo75]

Thank you!! Thank cleared it up.

[Steve A.]

So wouldn't reversing the red and green wires on both pickups accomplish that without having to rewire the coil tap switch? Like what you would do to one of them if the pickups were out of phase...
I have wired switches as Terry suggests but I think that it makes the pickup more susceptible to hum as the entire "dead" coil is connected to the hot signal and not to ground. Although I have not done extensive A/B testing on that theory, using digital recordings to compare noise levels.

Steve

P.S. So how do you like the 36th Anniversaries? I just got a set of them but haven't installed them yet. So how do they sound when you split the coils? Let us know how it works out when you rewire the switch (or reverse the main leads.)

[PoPo75]

Steve. So far the 36th anniversary pickups IMO sound incredible. If you are looking for high gain. Don't get them. They have a very vintage sound. Very "airy" sounding, for lack of a better word, almost P-90ish. While split they have a really nice single coil sound. With both pickups split and the switch in the middle position I get some really nice sounds. I am pretty happy with them.

[big_teee]

Steve, if you don't want Hum, I suggest you keep the pickup in Humbucker mode, and not Split it.
If You split a Humbucker and make it a Single coil, you're going to get hum, it doesn't matter which way you split it!
The way I usually wire them when split is ground the bridge, so you use the inside slug coil.
Then on the neck coil i use output on the neck to use the outside coil.
Use whatever works for you!
The short lead from the output to the switch should have no effect on noise.
Noise can travel on ground or output!
T

[Mark Hammer]

I installed a pair of Duncan P-Rails on my Epi Wilshire. The P-Rails can be run in dual-coil (HB) or each of two single-coil modes, Most folks will likely use a push-pull pot to cancel one of the coil. I used a pair of SPDT on-off-on toggles to get all possible options from the pair.
The common of the switch goes to the common of its corresponding pickup; i.e., the junction between coil 1 and coil 2. One of the side lugs goes to ground, and the other goes to the hot lead of the pickup. In the middle position, it's HB. In one side position the slender coil is bypassed by the switch, and in the other side position, the larger coil is bypassed by the switch. As you can see, all these options can be achieved in a rather simple layout. (The control layout is not stock. I cut a new pickguard and set things up my way, preferring a master volume and tone to duals.)

[Steve A.]

Steve, if you don't want Hum, I suggest you keep the pickup in Humbucker mode, and not Split it.

Actually I meant "buzz" and not "hum". In noisy RF environments you can get a buzz even from humbuckers if the guitar is not shielded. I've been making custom harnesses for my guitars for 30 years now and I've found that the shorter you keep signal leads the quieter the guitar. With the red, black and white leads all connected to the input of the volume pot you have the Hot (+) signal connected to the ~3,500 turns of pickup wire in the unused coil. In many cases you might not be able to hear the difference but you do in a noisy RF environment. (After GuitarNuts recommended star wiring for guitars 15+ years ago I am now using longer leads in my custom harnesses- before that I used to think of the signal return and ground leads as being interchangeable.)

In any case whenever possible I try to connect the unused coil to ground rather than the hot output.

Steve

[Steve A.]

I installed a pair of Duncan P-Rails on my Epi Wilshire. The P-Rails can be run in dual-coil (HB) or each of two single-coil modes, Most folks will likely use a push-pull pot to cancel one of the coil. I used a pair of SPDT on-off-on toggles to get all possible options from the pair.

I don't know if this applies to the P-Rails but for most double-coil humbuckers with 4+ wiring you can use a DPDT on-on switch for the dual-sound wiring first popularized by DiMarzio in the early 80's, or maybe even earlier. In one position you have the normal series-connected humbucker wiring; in the other you have the two coils connected in parallel for a thinner sound more like a single coil pickup but still humcancelling.

To get the single coil option you can use a special DPDT on-on-on mini-toggle switch, which in the middle position would connect the black and white leads. (If you use one of these switches instead of the regular ones it will drive you crazy trying to figure out why your wiring did not work as planned.)

http://www.dimarzio.com/sites/defaul...4Conductor.pdf

But before wiring up any fancy switches on a 2HB guitar test out the various possibilities with the bare leads and jumpers. There is no point in going to the trouble of adding switches which will give you sounds that you will not be using.

I was just now messing around with a set of DiM EJ Custom humbuckers and was wondering how a single coil switch would sound. The two coils on each pickup are very different from each other.*** With R connected to Hot and G connected to ground shorting the B/W leads to ground results in a very weak signal that is completely unusable. So I tried connecting the B/W leads to Hot and I got a decent single coil sound. Tap testing indicated that R lead connects to the slug coil while the G lead connects to the screw coil. So I will be redoing the connections so that G is connected to Hot, R is connected to ground and B/W will be connected to a DPDT push-pull to add a split coil to this guitar.

Steve

EDIT: If you add a DPDT on-on phase switch to the DPDT on-on-on mini-toggle switch it will allow you to select which coil is active in split-coil mode.

EDIT2: I always thought the on-on-on DPDT switch was specially designed for guitar wiring but I ran across a full-size on-on-on toggle switch in a huge circa 1960 rooftop furnace for the spray painting bay at a car body shop.

As for the wiring of these switches lets call the terminals on the left A, B, C and the terminals on the right D, E, F. With a typical DPDT on-on switch in one position B is connected to A and E is connected to D. In the other position B is connected to C and E is connected to F.

A . D
B . E
C . F

There are 3 position On-Off-On DPDT toggle switches with the middle position having no connections. However with the special On-On-On DPDT switch in the middle position you have B connected to C and E connected to D (or B connected to A and E connected to F.) I always ohm them out to figure which terminala are connected in the middle position.

*** I just ohmed out the coils on the EJ Custom and they were both roughly the same. I believe that the difference is in the magnetic field for each coil, something covered by one of the Steve Bucher patents.