Charvel San Dimas wiring question

noisepolluter

I’ve just bought a San Dimas HH with a 3 way blade switch and a push-pull coil split on the volume. Pickups are the usual JB/59 combo.

The coil combinations are as follows:
(with push-pull *in*)
Bridge Humbucker
both inner coils (not hum cancelling)
neck humbucker

(with p-p out)
Bridge outer coil
both outer coils (not hum cancelling)
Neck outer coil

I like all these sounds *except* the both-inner-coils middle combination. I’d much rather have the Gibson-style both-humbuckers sound.

Is there a way to tweak the connections so I can get that sound while still keeping all the outer-coil split sounds as they are?

ICBM

Yes. Just rewire the switch to the standard 3-way (Telecaster type) arrangement using the full humbuckers only, then use the pull-switch to split both pickups to ground, which if you want the outer coils on Duncan pickups will usually mean reversing the standard hot and ground connections so the greens are the hots and the blacks are the grounds.

noisepolluter

Thanks!

Does this diagram show exactly what I need to do?

https://www.seymourduncan.com/images/wiring-diagrams/2H_3B_1VppSPL_1T.jpg

ICBM

Yes. Just swap the greens and blacks on both pickups to leave the outer coils on.

noisepolluter

ICBM said:

Yes. Just swap the greens and blacks on both pickups to leave the outer coils on.

So the greens would instead connect directly to the 3-way switch, and the blacks would be soldered to the volume pot casing along with the bare wire (assuming bare wire is grey?)

ICBM

noisepolluter said:

So the greens would instead connect directly to the 3-way switch, and the blacks would be soldered to the volume pot casing along with the bare wire (assuming bare wire is grey?)

Yes, exactly.

fastonebaz

How does anyone understand this voodoo

noisepolluter

ICBM said:

noisepolluter said:

So the greens would instead connect directly to the 3-way switch, and the blacks would be soldered to the volume pot casing along with the bare wire (assuming bare wire is grey?)

Yes, exactly.

Good stuff. I’ll see if I can match that up with what’s in there right now and plan out what I’ll need to do. Thanks again!

Funkfingers

fastonebaz said:

How does anyone understand this voodoo

I explain it all in my forthcoming book, The Men Who Stare At Schematic Diagrams. 

Anyone who rewires enough electric guitars eventually gets the most popular circuits burnt into memory. It becomes possible to juggle ideas from multiple known circuits into novel permutations.

There is also a theory which states that decades of exposure to lead fumes from solder soften the brain.

ICBM

noisepolluter said:

Good stuff. I’ll see if I can match that up with what’s in there right now and plan out what I’ll need to do. Thanks again!

If I remember rightly the switch is a non-standard type with two separate wafers instead of one, but it operates in the same way.

You may not be surprised that I have done this exact mod for someone else... but it was a while ago.

skullfunkerry

fastonebaz said:

How does anyone understand this voodoo

Exactly this. I've tried & tried but I can't get it into my brain, I just don't understand it

noisepolluter

Ok.

I *think* I’ve got the push-pull volume pot wired up as per the diagram (except swapping the green pickup leads for black ones.)

I’ve also added a treble bypass widget between tags 1 and 2 (left to right as I look at them) on the volume pot.

I’ve now got a conundrum with the 3 way switch - see the photo in the link below.

Basically I’m presented with two wafers, each with 8 tags, some of which are currently linked horizontally with short leads.

I’m calling them left 1-8 and right 1-8 working from top to bottom, as I look at the photo. The neck pickup is at the top.

Left 1 and right 1 are currently linked, and there’s a white lead running off right 1 to tag 1 on the volume pot (and then on to the time pot).

Left 2 is linked to left 3, and there’s a short green lead off left 3 which is now flapping around in the breeze - it was previously connected to the push-pull.

Right 2 has nothing on it.

Right 3 is connected to right 4, and right 4 then has a short blue lead trailing loose (again, was previously connected to push-pull).

Left 4 has nothing connected.

Left 5 and right 5 have nothing connected.

Left 6 and right 6 are linked. Left 6 also has a black lead running to the casing of the tone pot. 

Left 7 and right 7 have nothing connected.

Left 8 has a short red wire trailing loose (previously connected to push-pull).

Right 8 has a short white wire trailing loose (was on push-pull).

Also currently flapping loose are the both green pickup leads (I’m calling them bridge green and neck green).

Please could some superhuman, quite possibly @ICBM ,  advise me what connections I need to make now? 

Edit: I’ve attempted to do a diagram in the hope of making this post slightly less surreal - NB the squiggle between L6 and L7 is just a crossed out mistake, please ignore 

https://flic.kr/p/2jBmsYi


Here is a picture of the rat’s best for you to enjoy in the meantime:

https://flic.kr/p/2jBgooH

Profuse thanks in advance!

ICBM

It's quite difficult to describe...

There are two easy(ish) methods -

1. Start by removing all the connections from the existing switch. Then you should be able to see which are the rotor connections - two of those need to be connected to the two pickup hots. If you take the switch out of the guitar it should be possible to see which connections each one needs to go to in each of the physical switch positions - either have a look at it as you move the switch, or use a multimeter with a continuity tester.

2. Easiest of all - just replace it with a standard CRL 3-way switch! Then you can use the standard Tele-type diagram. Obviously this will cost a little more, but it also has the advantage that you can simply cut all the old wires - leaving a short piece of the coloured plastic on each so you can easily see which goes where - so you could put it back to stock if you ever wanted to. (Or to include in the case if you sell the guitar...)

noisepolluter

Thanks John - should one pickup be connected to one wafer and the other pickup to the other wafer? (and each wafer be connected separately to tag 1 on the volume pot?)

ICBM

noisepolluter said:

Thanks John - should one pickup be connected to one wafer and the other pickup to the other wafer? (and each wafer be connected separately to tag 1 on the volume pot?)

It would probably be easiest to wire it like that, or some of the connections will be harder to get at. I can't remember what I did on the one I worked on - the problem for me describing it to you is that I just took the switch out and then it was instantly obvious to me what went where, but I know you may not have this specific obsessive talent .

noisepolluter

ICBM said:

noisepolluter said:

Thanks John - should one pickup be connected to one wafer and the other pickup to the other wafer? (and each wafer be connected separately to tag 1 on the volume pot?)

It would probably be easiest to wire it like that, or some of the connections will be harder to get at. I can't remember what I did on the one I worked on - the problem for me describing it to you is that I just took the switch out and then it was instantly obvious to me what went where, but I know you may not have this specific obsessive talent .

I’ll have a look in the daylight. I might be able to suss out how it works rather than just relying on trial and error - or I could order a simpler switch! 

Edit: I wonder if it’s one of these:

https://www.premierguitar.com/articles/27090-mod-garage-meet-g%C3%B6ldos-double-wafer-3-way-switch

ICBM

noisepolluter said:

Edit: I wonder if it’s one of these:

https://www.premierguitar.com/articles/27090-mod-garage-meet-g%C3%B6ldos-double-wafer-3-way-switch

Yes, I think it might be.

If it is then the easiest is just to use one wafer, connect all four of the middle terminals to the volume control, and then the two end ones to the pickup hots, each at the same end as the pickup physically is.

In fact I think that's what I might have done, since I think I remember leaving the link wires in place to the other wafer, as they don't matter.

Funkfingers

The stock selector switch is a 4-pole three-way.

Terminals L1-4 and R1-4 are already doing the basic Telecaster neck/both/bridge thang.

L1 and R1 are the common/collector/wiper terminals for their respective poles.

L2/3 should the hot conductor from the bridge pickup.

R3/4 should be the hot conductor from the neck pickup.

The relevance of the two unconnected insulated wires at L3 and R4 depends upon how the push-pull switch was originally wired up.

•

Terminals L5-8 and R5-8 govern the automatic coil split when both pickups are selected. 

L8 and R8 are the common/collector/wiper terminals for their respective poles.

L6/R6 is the ground for the coil splittage.

My preference would be to have this bridged connection at L8/R8. The individual series/split connection for each pickup could then go to L6 and R6, respectively.

noisepolluter

So it looks like there are two possible approaches @ICBM  and @Funkfingers  - would either of these allow me to keep the push-pull volume wired up as set out in the Seymour Duncan wiring diagram earlier in the thread (i.e. just the pickup green wires going into the switch), or will it need re-wiring so that other pickup wires are also connected?

Funkfingers

ICBM’s suggestion of a sprung CRL two-pole selector switch plus a push-pull coil split is by far the simplest and most durable wiring option.

Having automatic AND push-pull coil splittage switching only makes sense if one of these options is partial splittage via a capacitor and/or resistor.

If you are already inclined to remove the stock selector switch, it might be wiser to change to a five-way Superswitch wired like either a Fender Double Fat Stratocaster, the Musicman Axis Supersport or the ever-popular Ibanez five-way HH circuit.

noisepolluter

ICBM said:

noisepolluter said:

Edit: I wonder if it’s one of these:

https://www.premierguitar.com/articles/27090-mod-garage-meet-g%C3%B6ldos-double-wafer-3-way-switch

Yes, I think it might be.

If it is then the easiest is just to use one wafer, connect all four of the middle terminals to the volume control, and then the two end ones to the pickup hots, each at the same end as the pickup physically is.

In fact I think that's what I might have done, since I think I remember leaving the link wires in place to the other wafer, as they don't matter.

@ICBM so that would be, for instance:

L1: neck pickup green wire
L2: nothing
L3-6: bridge a wire across all of these, and run it to volume pot tag 1
L7: nothing
L8: bridge pickup green wire

(Or is it L1-2 neck, L7-8 bridge?)

basically adapting the switch to be like a normal tele one?

Funkfingers said: ICBM’s suggestion of a sprung CRL two-pole selector switch plus a push-pull coil split is by far the simplest and most durable wiring option.
Having automatic AND push-pull coil splittage switching only makes sense if one of these options is partial splittage via a capacitor and/or resistor.

If you are already inclined to remove the stock selector switch, it might be wiser to change to a five-way Superswitch wired like either a Fender Double Fat Stratocaster, the Musicman Axis Supersport or the ever-popular Ibanez five-way HH circuit. I do actually quite like the single coil bridge and neck sounds, having spent a bit more time with them. There’s something pleasingly brash and cutting about them. 

I’ll have a crack at the wiring @ICBM described with the current switch, and plan B will be getting a 2 pole 3 way. 

Thanks both - you’ve been extremely helpful and patient.