Split Humbuckers, Single Coils, and Polarity

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mpatricklesley

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My current project is my take on a Thinline t-type. I'm planning to use a humbucker in the bridge and a single coil in the neck. I want to be able to split the humbucker to get some additional tonal versatility. I understand the wiring for that but I'm getting myself wrapped around the axle regarding polarity.

PLEASE correct me if I'm wrong, but here are my basic assumptions:
-To have to two single coil pups be in phase, one must be RWRP.
​​​​​​-In a SD humbucker, the south coil (red and green) is RWRP.
-An off the shelf SD single coil is not RWRP unless otherwise specified.

Ok, so operating off those three assumptions, if I split the coils in the middle position, and want and in phase sound, I need to send the north coil to ground, yeah? If I look at the SD wiring diagram for this (below), I'm pretty sure it shows grounding the south coil. IF I'm correct about that, the solution is just to switch wires - put the green on the blade and the black to ground on the pot?

Also, shouldn't the cases of the volume and tone pots be connected so the volume pot has a ground connection?

Wisdom would be appreciated.

https://www.seymourduncan.com/images/wiring-diagrams/Tele_1H_1S_3B_1VppSPL_1T.jpg
 
mpatricklesley said:
To have to two single coil pups be in phase, one must be RWRP.
Click to expand...

Not exactly. RWRP is for noise cancelling. RW makes it noise cancelling, but puts it out of phase. RP brings it back into phase. Reversing the wires would do the same thing. Two neck singles would be in phase. They just wouldn't noise cancel. (Which is what a humbucker does differently.)

In a SD humbucker, the south coil (red and green) is RWRP.
Click to expand...

No. Both coils of a humbucker are wound the same direction. They achieve noise cancelling by being connected internally "backwards". (Reversing the wire connection as noted above.) Polarity is brought back by the lay of the magnet. One coil gets the N side, and one coil gets the S side.

An off the shelf SD single coil is not RWRP unless otherwise specified.
Click to expand...

Correct. You must specify, or order, an RWRP.

Ok, so operating off those three assumptions, if I split the coils in the middle position, and want and in phase sound, I need to send the north coil to ground, yeah? If I look at the SD wiring diagram for this (below), I'm pretty sure it shows grounding the south coil. IF I'm correct about that, the solution is just to switch wires - put the green on the blade and the black to ground on the pot?
Click to expand...

If you split a (SD) humbucker to the stud coil, (red/white to ground), you mate it with a neck single. If you split an SD humbucker to the screw coil, (red/white to black), you'd mate it with an RWRP single. I've always had trouble thinking in terms of north and south coil. I think in terms of stud and screw.

Also, shouldn't the cases of the volume and tone pots be connected so the volume pot has a ground connection?
Click to expand...

Yes.

Singles attain noise cancelling by RWRP. They reverse the wind and reverse the rod magnets. Humbuckers achieve noise cancelling by reverse wiring (the coils) and reverse magnet polarity.

I know it's confusing.
 
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A quick summary of above:

They're are two ways to noise cancel two coils: Wind one the opposite direction. (RW) Or connect them backwards. Start to start, or finish to finish.

They're are three ways to reverse polarity. Reverse wind the coil. Connect the coils backwards. Reverse polarity of the magnet.

You choose which noise cancelling method you want. (Singles and humbuckers do it the opposite way.) Then you bring it back into polarity with one of the other three ways.

Technically, phase is incorrect, but it's what everyone calls it. Like calling the vibrato arm on a Strat the tremolo arm. It's just accepted guitar vernacular.
 
It's not confusing when it's explained well, which I appreciate. Thank you for taking the time to correct my misconceptions.

And now we know why I spend my time planing, sawing, and gluing wood instead of trying to also wind pickups. There's just not enough space in my gourd to keep it all straight.
 
I wish I had better wood working skills.

P.S. Above, I said a humbucker has its wire connected backwards internally. That's on a standard 2-conductor, or co-axial cable. On a 4-conductor, it's your job to do that as in red and white together.
 
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Building an electric guitar isn't really much more than careful measuring and good gluing, especially if you build Fender style guitars (which I do)

The biggest obstacle is having access to the machines for doing the rough shaping work and whole lot of clamps. I'm extraordinarily lucky that the high school where I teach still has a good woodshop and I have a good relationship with the guy who runs it, so I just learned to build guitars by screwing stuff up after work.
 
Just plain old boring Titebond. The glue seems aren't *quite* as fine as if you use hide glue, and it's not ever coming apart. That said, I do my bolt on necks using threaded inserts and actual bolts, so ever needing to steam a neck off isnt really a thing for me and it's still REALLY strong.

Also, since I'm in my mid 40s, I'll probably be dead before anything I'll ever build will need to be renecked, so I could probably just Titebond them in anyway :D
 
My luthier friend did a cool guitar with hide glue. (I'll check and see if I can post a pic.) But I think he uses Titebond for headstock repairs.

I'm meandering into my 70's.
 
I don't think the glue type really makes a lot of difference in the time or playability of an electric guitar, but the guys doing those builds with hide glue are craftsmen so far above me. I've chatted with people who actually have to practice their glue ups because the open time on hot hide glue is so short. I will build a very playable and good looking instrument, but I'm a hack compared to them.
 
This is the last one I built for myself. Spalted hackberry (bookmatched) top and back, cherry neck, Brazilian rosewood fretboard. Two handwound jazzmasters because I like single coils but wanted something different.

PXL_20240626_204313182~2.jpg
 
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