Musicman JP6 Pickup Swap Confusion (With Added Circuit Board)

Fiftyshadesofjay

Hi all, looking to replace the Dimarzio Pickups in my Musicman JP6 with some Lace Alumitones I have.

Really struggling with the wiring on this, the lace pickups have four wires while I have 5 on the Dimarzio's. Problem I'm having is the Dimarzios are wired to a circuit board so I'm planning to leave them soldered and snip the wires higher up.

Unfortunately I can't work out which wire to connect to each and also where to stick the extra wire, any suggestions?

I believe they're in full humbucking mode either position of the three way switch and then both split in the middle position if it helps.

Attached some photos too. Thanks!

<a href="https://imgur.com/SVVEAnp"><img src="https://i.imgur.com/SVVEAnp.jpg" title="source: imgur.com" /></a>

<a href="https://imgur.com/snVf74E"><img src="https://i.imgur.com/snVf74E.jpg" title="source: imgur.com" /></a>

ICBM

Going by this http://www.lacemusic.com/pdf/14.pdf and looking at your pic of the PCB, it looks like:

Green (shield) goes to where the bare wire is on the PCB.
Orange (hot) goes to where the green wire is on the PCB.
White/black (ground) goes to where the red wire is on the PCB.
White (coil split) goes to where the white or black wires are on the PCB, doesn't matter which.

At least I think so!

I would unsolder the DiMarzio wires cleanly from the PCB, not snip them. You have this photo for reference if you want to put them back.

Fiftyshadesofjay

ICBM said:

Going by this http://www.lacemusic.com/pdf/14.pdf and looking at your pic of the PCB, it looks like:

Green (shield) goes to where the bare wire is on the PCB.
Orange (hot) goes to where the green wire is on the PCB.
White/black (ground) goes to where the red wire is on the PCB.
White (coil split) goes to where the white or black wires are on the PCB, doesn't matter which.

At least I think so!

I would unsolder the DiMarzio wires cleanly from the PCB, not snip them. You have this photo for reference if you want to put them back.

Awesome thank you, I shall give it a go tomorrow! Much appreciated.

I m ow what you mean about snipping, I just figured there’s less chance of damaging the PCB if I do that, ie I don’t trust myself.

Funkfingers

I interpret the colour codes as follows.

HOT = Lace Orange = DiMarzio Red
SCREEN = Lace Green = DiMarzio Bare
HB -ve = Lace White with Black Stripe = DiMarzio Green
SPLIT = Lace White = DiMarzio White and DiMarzio Black 

The link between the DiMarzio black and white conductors is achieved on the PCB. On the Lace pickup, this link occurs inside the pickup.



To complicate matters, the JP6 uses a 4P3T on/on/on pickup selector switch, offering Neck HB, Inside Coils, Bridge HB. To achieve noise-cancellation in the inside coils selection, the relationship between the coil winding directions and magnetic polarity needs to be correct. 

On a guitar such as the Fender Big Apple / Double Fat Stratocaster, noise-cancellation for the Inside Coils permutation is achieved by reversing the bar magnet polarity in one of the pickups and connecting up the conductor wires from each coil in the reverse order to normal. This requires four conductor + shield output cable. 

In my opinion, it is not possible to preserve the original JP6 switching with three-con + shield humbuckers. I would be happy to be corrected about this.

Fiftyshadesofjay

Funkfingers said:

I interpret the colour codes as follows.

HOT = Lace Orange = DiMarzio Red
SCREEN = Lace Green = DiMarzio Bare
HB -ve = Lace White with Black Stripe = DiMarzio Green
SPLIT = Lace White = DiMarzio White and DiMarzio Black 

The link between the DiMarzio black and white conductors is achieved on the PCB. On the Lace pickup, this link occurs inside the pickup.



To complicate matters, the JP6 uses a 4P3T on/on/on pickup selector switch, offering Neck HB, Inside Coils, Bridge HB. To achieve noise-cancellation in the inside coils selection, the relationship between the coil winding directions and magnetic polarity needs to be correct. 

On a guitar such as the Fender Big Apple / Double Fat Stratocaster, noise-cancellation for the Inside Coils permutation is achieved by reversing the bar magnet polarity in one of the pickups and connecting up the conductor wires from each coil in the reverse order to normal. This requires four conductor + shield output cable. 

In my opinion, it is not possible to preserve the original JP6 switching with three-con + shield humbuckers. I would be happy to be corrected about this.

The plot thickens! If I wired it as above would it still split the coils in middle position? The original pickups have quite a unique split sound at the moment

ICBM

Funkfingers said:

I interpret the colour codes as follows.

HOT = Lace Orange = DiMarzio Red

If you look at the PCB in Fiftyshadesofjay's post, you can see there is a PCB trace running round from the red to the bare, so red = ground, not hot.

Funkfingers said:

To complicate matters, the JP6 uses a 4P3T on/on/on pickup selector switch, offering Neck HB, Inside Coils, Bridge HB. To achieve noise-cancellation in the inside coils selection, the relationship between the coil winding directions and magnetic polarity needs to be correct.

It will be in any series humbuckers. The only question is whether you get the 'correct' coils (inner or outer) active in the split position. There's no way of telling this from the Lace wiring diagrams.

In fact, if it is wrong, then swapping the hot and ground wires (orange and white/black) will fix it.

Funkfingers said:

In my opinion, it is not possible to preserve the original JP6 switching with three-con + shield humbuckers. I would be happy to be corrected about this.

It is, because the black and white wires from the DiMarzios are connected together on the PCB (there's a trace visible between the two pads) which is no different from having them connected in the pickup - they're effectively wired 3+shield anyway.