polarity questions

[timand]

I have a Seymour Duncan JB jr in the bridge position of my strat which I love. The tapped leads end up at a volume pot instead of a switch which gives me better tonal situations. Black is hot, white and red go to tapped volume pot, green is ground. The duckbuckers in the middle and neck have hot red wires. My question is that I will be adding two Fralin Blues specials in
the middle and the neck. According to Lindy, the polarity of his pick ups
cannot be changed, but because my Duncans have four wires they can.
Evidently on the Fralins the white is hot. What's the best way to handle
the situation. So if the polarities are different, would I then change the polarity of the JBjr by soldering the black and the red together at the volume pot and send the white to the switch?

Any help is appreciated - I'm new at this so be gentle..

 

[rockerdaveuk]

Re: polarity questions

I have had a polarity problem on my Strat with a Lil 59 bridge , Kent Armstrong STV-1 neck and STV1-R middle. The first problem was that I had to swap the STV,s around so the middle Pu would humcancel with the front coil of the Lil 59 . The second and biggest problem was the polarity between the STV,s and the Lil 59 which I cured by connecting the Lil 59 as follows :-
White - Hot
Black/Green - Tapped
Red - Ground
Hope this helps

 

[Lewguitar]

Re: polarity questions

I have a Seymour Duncan JB jr in the bridge position of my strat which I love. The tapped leads end up at a volume pot instead of a switch which gives me better tonal situations. Black is hot, white and red go to tapped volume pot, green is ground. The duckbuckers in the middle and neck have hot red wires. My question is that I will be adding two Fralin Blues specials in
the middle and the neck. According to Lindy, the polarity of his pick ups
cannot be changed, but because my Duncans have four wires they can.
Evidently on the Fralins the white is hot. What's the best way to handle
the situation. So if the polarities are different, would I then change the polarity of the JBjr by soldering the black and the red together at the volume pot and send the white to the switch?

Any help is appreciated - I'm new at this so be gentle..

Just reverse the black and green wires on the JB JR. if you need to reverse the phase. I think you will probably have to. Lew

 

[Lewguitar]

Re: polarity questions

The Polarity of the polepieces of a single coil cannot be changed. But you can put any single coil with two conductors in phase relative to another pickup by just reversing the white and black wires of the single coil. Lew

 

[timand]

Re: polarity questions

Just reverse the black and green wires on the JB JR. if you need to reverse the phase. I think you will probably have to. Lew

According to Lindy you cannot do that with his pickups - I asked

 

[Lewguitar]

Re: polarity questions

According to Lindy you cannot do that with his pickups - I asked

You can.

Just reverse the black and white wires. That will not reverse the POLARITY. But it will put a pickup that is OUT OF PHASE with another pickup IN PHASE.

You CANNOT REVERSE THE POLARITY...that is determined by the way the magnetic pole pieces are magnitically charged and you cannot change that yourself.

You CAN REVERSE THE PHASE relative to a pickup that is out of phase with it to get rid of the thin nasal tone tone when the two are combined.

I've done it many times!

Lew

 

[Lewguitar]

Re: polarity questions

You can approach this either of two ways:

1. reverse the black and green wires of the JB JR. if you need to.

2. OR: reverse the black and white wires of the Blues Specials and leave the JB JR wired the way it is now...if you need to.

Lew

 

[Lewguitar]

Re: polarity questions

I hope you understand now that POLARITY and PHASE are two differant things. You cannot change the polarity...you can change the relative phase by reversing the hot and ground of one pickup if it is out of phase when combined with another pickup.

Lew

 

[Robert S.]

Re: polarity questions

I wouldn't mess with the Fralins wiring. It is possible with the SD 4 conductor wiring to get both the proper phase and polarity on the JB jr to match the Fralins.

Wiring the JB jr green hot/black ground will change the polarity.

Wiring white hot/red ground will change the phase.

Wiring red hot/white ground changes both.

 

[Lewguitar]

Re: polarity questions

I don't believe you can change the polarity of the polepieces by reversing any wires.

That is a function of the magnets and the way they are aligned/installed.

The JB JR. has the magnets under the coils and glued in place. They cannot be reversed.

If a polepiece has a north polarity on top, messing with the wires will not make it have a south pole on top.

So when Lindy says you cannot change the polarity of his pickup he is correct.

Lew

 

[Robert S.]

Re: polarity questions

In a humbucker you have two coils, one north poled and one south poled. With SD humbuckers the north pole bobbin is the non-adjustable bobbin (inner usually). You can change the magnetic polarity of SD humbuckers simply by which wire you choose to use as your hot. Using the black or white wire gets you a north polarity humbucker, using green or red gets you a south polarity humbucker.

The phase is simular in the respect that you can phase the individual coils for clockwise or counter clockwise depending on which lead you choose. The north coils (stud- non-adj.) phase can be changed by choosing the white lead instead of the black and the same can be done on the south coil.

If the Fralins are top north, use the green lead for hot and the magnetic polarity tssue will be resolved. If the pickups are then out of phase, use the red as hot and the white as ground and you will have the proper wind direction as well.

 

[Lewguitar]

Re: polarity questions

In a humbucker you have two coils, one north poled and one south poled. With SD humbuckers the north pole bobbin is the non-adjustable bobbin (inner usually). You can change the magnetic polarity of SD humbuckers simply by which wire you choose to use as your hot. Using the black or white wire gets you a north polarity humbucker, using green or red gets you a south polarity humbucker.

The phase is simular in the respect that you can phase the individual coils for clockwise or counter clockwise depending on which lead you choose. The north coils (stud- non-adj.) phase can be changed by choosing the white lead instead of the black and the same can be done on the south coil.

If the Fralins are top north, use the green lead for hot and the magnetic polarity tssue will be resolved. If the pickups are then out of phase, use the red as hot and the white as ground and you will have the proper wind direction as well.

I think the end result is what's important. And I'll trust that what you're suggesting will result in the pickups being in phase.

But I do not agree that you can

change the magnetic polarity of SD humbuckers simply by which wire you choose to use as your hot.

Oh well: MERRY CHRISTMAS! :laugh2: :laugh2: :laugh2:

 

[Robert S.]

Re: polarity questions

Lew, thats exactly you happens when you use green for hot to match SD HBs with Fender single coils. North or south polarity in HBs is decided by which coil the signal hits first.

Merry Xmas to you too Bro!

 

[Lewguitar]

Re: polarity questions

Lew, thats exactly you happens when you use green for hot to match SD HBs with Fender single coils. North or south polarity in HBs is decided by which coil the signal hits first.

Merry Xmas to you too Bro!

Thanks Robert!

Maybe I'm missing something, but This is my understanding:

The flat magnet under and between the bottem polepieces of the two coils has two long edges roughly 1/8" x 2 1/2".
One 1/8" x 2 1/2" edge is the north pole of the magnet and the opposite 1/8" x 2 1/2" edge is the south pole of the magnet.

If the north pole edge of the magnet is resting against the six slug polepieces then the six slug polepieces will be north at the top and the six screws will be south at the top. If the south pole edge of the magnet is resting against the six slug polepieces, then the six slugs will be south polarity and the screws will be north.

I don't think there is anything you can do to the wirng to change that.

After making the changes to the wiring you described, I still think if the slugs , just as an example, were north polarity originally, they'll still be north polarity.

But I don't doubt that the changes you described will get everything in phase and working properly.

Lew

 

[rspst14]

Re: polarity questions

I think Lindy would know better than we would, so if he says polarity can't be changed on his pickups, I would tend to believe him. If a single coil pickup's polarity could be changed simply by wiring it differently, then what's the purpose of producing them in a RW/RP version? I think Robert is right, you can change the polarity of a humbucker, but I don't think you can with a true single coil. I could be wrong, but either way, all you need to worry about is the phase relationship, not the polarity. Go to www.kinman.com, there's an explanation of how to check if two pickups will be in phase with each other before you install them.

Ryan

 

[Robert S.]

Re: polarity questions

Yes the north bobbin will always be north, but there is a relationship of current flow to the bobbins wind direction that you are missing. If the current flows into the circuit from the north bobbin start wire there will be a 180 degree magnetic phase difference than if it flows off of the south bobbin start wire.

Since both bobbins are wound in the same direction and both the green and the black are both start wires, the overall wind direction is the same using the green or the black lead as hot. To change the wind direction you need to use the white and red wires as hot and ground.

This stuff made no sense to me either until I had to figure out how to make a SD bridge HB work with a PRS neck HB using the PRS 5 way switching. Remember, its not the physical proximity or relationships of all the components in a HB or between two single coils that make the phase and polarity stuff work out, it's what happens electrically to the signal.

 

[Robert S.]

Re: polarity questions

With the Fralins, the baseplate may be grounded with one of the wind wires so changing the polarity by simply swapping leads would cause a lot of unwanted noise. The pickup would still produce sound, but it would also act as an RF antenna.

 

[Robert S.]

Re: polarity questions

Poor timand........

Don't worry Bro, you can make the Fralins work with the JB jr.

 

[Lewguitar]

Re: polarity questions

With the Fralins, the baseplate may be grounded with one of the wind wires so changing the polarity by simply swapping leads would cause a lot of unwanted noise. The pickup would still produce sound, but it would also act as an RF antenna.

Even with a bassplate, all you need to do is move the bare wire soldered to the bassplate and the black wire to the white wire on the bottem of the pickup. Then you can reverse the white and black wires at the switch and back of the volume pot and all will be well....if you need to reverse the phase of the single coil pickup.

I think Lindy is correct: You can change the phase relationship to get two pickups in phase with each other....but you cannot change the polarity of a single coil Strat type pickup. Lew

 

[rockerdaveuk]

Re: polarity questions

Lew is right to say that Polarity is the way the magnets are fitted. In my earlier reply I should have said Phase instead of Polarity (sorry). One reason that I connected my Lil 59 why I did was so when the PU was split (center tap grounded) it would still be the front coil that was on. Because of string alignment problems it is better for me to use the front coil. If I had swapped the green and black wires the phasing would be correct but it would then split (again center tap grounded) to the back coil .