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I'm going crazy here trying to figure out what is wrong with this guitar. New Duncan 59's and I need one volume, two tones, and coil split each using push pull pots. If you look at this diagram:

http://www.guitarelectronics.com/produc ... -Taps.html



I don't have it wired like that. I have it wired such that both pickups are wired like the neck pickup in that diagram. That is to say that the red and white wires (Duncan color codes) are sent to ground to cut out one of the coils. However if you look at the diagram their bridge pickup is not wired the same way. It looks like in that case when you flip the switch instead of sending red and white to ground it joins red/white and black together. I guess that would cut a coil but I am not getting it.

My problem is the way I have it wired the neck pickup when split doesn't sound right. It sounds more like an out of phase wiring. The bridge pickup sounds great. I cannot for the life of me figure out why it sounds wrong. It seems to me that each pickup is isolated to the coil split switch and that one would have no effect on the other at all. But something is not right with the sound. IS it some sort of ground loop? I know for a fact I have wired guitars with two volumes and one tone in a similar fashion with no problems. Anyway Arghhh!

Anyone have any ideas?

You are correct that the two coil taps in the schematic are slightly different. In both cases though the coil tap is shorting out one of the coils. Their neck coil tap shorts out what they call the "south" coil, so only the north coil is heard. On the bridge pickup they short out the north coil, so you only hear the south. My guess is that they did it that way so that when you have both pickups selected and full up you have one north and one south coil which is necessary if you want the hum to be bucked.
Ground loops affect hum, but they don't distort the tone.
My guess is that your dissatisfaction with the tone of your split neck pickup is because of which coil you are hearing. The coil with the screws in it always sounds different than the one with the slugs in it, especially if the pickup is far from the strings and the screws are unscrewed a lot (close to the strings). If you touch the polepieces with a small piece of metal, a tiny screwdriver, while listening through an amp you can diagnose which of the coils your circuit is shorting out. The cure would be to rewire the neck pickup to short out the other coil, like the bridge pickup in the diagram.
I hope this helps. Incidentally if you like the idea of having the hum bucked when using both pickups together and coilsplit, you do need to have a north and a south coil turned on. Diagnose this with a compass. If the two coils that sound best are the same polarity, I have heard that you can take the pickup apart and flip the magnet so the end formerly facing the screws now faces the slugs, reversing the polarity.

That does help greatly. Thanks for that.

Turns out there is something very wrong with this pickup. I got ta tell ya too this has been driving me mad. Learning experinece for sure. When someone comes to the shop and says they tried to wire a guitar, failed, and now needs help tell them that it might cost them 5 times the normal price!!!!!!!

Cripes... I know why I mostly stick to acoustic work.

I used to to do much more electric guitar stuff and never had such a hard time. I knew I was wiring it correctly as I still have all these guitar wire diagrams in my head.

Anyway. Testing the pickup looked fine using my ohm meter. You could see the resistance across one coil then across the other that would indicate that the coil was split or full humbucking but it just doesn't sound right. So I wired the pickup straight to a jack. Black wire to hot and green to ground with the red and white tied off. You tap on both coils with a screw driver and can hear that they are both active but the pickup sounds out of phase. There is a huge volume drop and you get that tinny out of phase sound. Then ground out the red/white wires and tap on the coils and only the screw pole piece coil is active and it sounds right and volume increases..

So I can only guess that there is some weird short inside the wire bundle or the pickup itself that is causing one coil to start and finish the wrong way. There is no way that this pickup is designed to sound like this. I can see by tapping the pole pieces and a resistance test that both coils are active but there is a big volume drop and it sounds out of phase. My personal guitar has out of phase switching, I love it when appropriate, and I know what it sounds like and this pickup is doing it. Driving my crazy.

If anyone has any ideas as to how this could happen I'd love to know.

What kind of pickup? If the coils are too tightly matched, I imagine it could have an out of phase sound in parallel.

I would check the following

- DC Ohms for each coil

- Verify color codes for wiring. Make sure the coil cut wires are indeed the correct ones.

- Magnet Polarity. This is a stretch but magnets can get damaged or de/re-magnetized.

I would check the really obvious stuff. If everything looks like it should, then the problem is probably internal like a shorted out coil. This happens with really old pickups.

I think there are people out there learning to wind pickups and they foolishly rewind Duncan's, DiMarzios, etc. in an attempt to improve on them and when they realize they made them worse, they sell them on eBay. Not saying this is what you have. Just saying "who knows?".






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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

It was a brand new Seymour Duncan classic '59. Turns out that they screwed up the color codes. I've never seen this happen before! It was the black and white wires that connect the coils and needed to be grounded out rather then the red/white. That is actually the Dimarzio color code but hey what ever works.

One of my favorite humbuckers.

It is easy to mess up the color codes when building a pickup. I agree it's strange coming from Seymour Duncan. Often times the lead wires coming off of the coils are simply black and white. It makes sense that someone just got confused while dealing with all those tiny yet similar wires. Happens to the best of us.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Yeah I can see how easy it would be to make that mistake. they are great sounding picups and the coil split really does sound good too.