Variation on the Gilmour neck PU always on Strat Mod (series linked)

[Gerry Hayes Haze Guitars]

Hi Iker

We talked a little offline on this but I want to check with you on some hardware questions and also to get some clarification on exactly what you’re hoping to achieve

You mentioned a St.Vincent guitar so we’re taking about three pickups. You also mentioned a 3-way switch instead of a 5-way.

First question is what pickup selections you want. With a 3-way switch, there’s not so much choice so I’m guessing it’s just bridge/middle/neck one at a time.

This being the case, you want an option to bring in the neck pickup in series with EITHER the bridge or middle? Is that right?

Regarding the existing pickups? What are their hook-up cables like? Are they two wire pickups. Are they four wire? Are they braided cable.

If you can let me know, I’ll have a think about this. First thoughts are that, if you’re hoping to get the neck in series with either of the others, it probably complicates things but we’ll keep our fingers crossed.

Oh, lastly, are you open to different hardware/switches if needed?

[iker elorriaga ieL]

Hey Gerry!

Yeah, it’s a St Vincent model, 3 pickups, 3 position lever switch, BRIDGE-MIDDLE-NECK, 1 volume, one tone. Ideally I would like to bring the Bridge pickup in series with the neck pu, or with the middle pickup. I don’t want the 3 pickups together, I don’t care about that option.

I hope this clarifies, if you need anymore explanation, please tell me.

Cheers!!!

[iker elorriaga ieL]

I forgot, the pickups are mini humbuckers and in the guitar I have, that is the Sterling version, they have a single coductor, a braid around it and insultion wraping everything up. And yes I am open to different harware or switches if needed. I would like the most simple option possible, I mean simple to operate, I don’t care about modding the guitar at all.

Thanks Gerry!

[Gerry Hayes Haze Guitars]

Ok. Bad news. The pickups here mean we can’t easily accomplish what you’re looking for.

Let me try to explain why. Check out the drawing which might make this easier to see.

The individual pickups are typically combined in parallel. The positive wire from each pickup gets joined together somewhere (maybe via the switch for instance) and all the negative wires are usually joined together at a ground point like a pot case.

When we connect pickups in series, we take the positive wire from one pickup and join it to the negative wire from another. The current then flows through each pickup, one after the other.

If you imagine a couple of Strat pickups, this is straightforward. The white wire from one pickup is connected/switched to the black wire from another and that connects them in series. With a four-wire humbucker, we can do something similar.

However with a two wire humbucker with the braided sheath, the negative wire also serves as the pickup’s ground/shield connection (it’s connected to the pickup’s metal base plate and metal cover). That means, if you were to join these types of pickups in series, for one pickup, that sheath, base plate, and metal cover are now carrying the hot signal too. Things will become incredibly noisy. Too noisy to be useful.

Long story, short: Connecting these pickups in series isn’t really practical. Sorry.

Hope this all makes sense.

[Gerry Hayes Haze Guitars]

I should mention for completeness that it is possible to rewire the internals of the pickups in order to add a separate wire to act as the pickup’s ground/shield. It tends to be a pretty fiddly job though so you’d have to really want a series connection.

I should also mention that, since you mentioned these were braided pickups, I haven’t actually spent the time to work out a circuit to see if the actual switching is possible. 😄 If you’re determined enough that you’re considering rewiring pickup internals, let me know so I can think about the rest of it.

[iker elorriaga ieL]

Hey Gerry, yeah, I can open the pickups and get get the 4 conductors out, and wax pot them again, no problem

[iker elorriaga ieL]

Gerry, I also have a 5 way lever style superswitch I could use but if it’s possible I’d like to use the 3 position lever Tele, or old strat switch and either a push-push pot to get the bridge PU in series in, or a 2 position mini toggle switch. Thanks!!!

[Gerry Hayes Haze Guitars]

Ok. First thing is that I need to put on a big disclaimer. Since you’re committing to a reasonable amount of work to modify and pot three humbuckers, I’d feel better if you were able to test this before doing all that work. I think it should work but haven’t done any extensive testing. The ideal would be if you happened to have three Strat pickups lying around and could mock up a prototype circuit to be sure.

That said, this seems to make sense in my head so hopefully it translates to reality.

The problem with this is trying to keep the pickups isolated and not accidentally link them causing issues. I think I’ve managed to do this by separating the bridge and middle negative (ground) wires and controlling them via the second side of the switch. That way, each is only connected to ground when that position is selected. Then we can interrupt that ground connection and join it to the neck hot wire via the push-pull.

I’ve used Seymour Duncan colours for this so you’ll need to transpose if you have different hook-up wire colours.

The neck negative (ground) is soldered to a pot as normal. The bridge and middle negatives go via the switch. The pickup series links (if you choose to expose them when rewiring the pickups) will just be soldered together and taped as usual. All bare wires for pickup shielding are soldered to a pot case too.

Hope this (a) makes sense and (b) actually works.

[iker elorriaga ieL]

Thanks Gerry, I love you, man! Yeah, I do have a set of strat pickups to do a “dry run”. I’ll keep you posted with the results.

ie_

[Gerry Hayes Haze Guitars]

Addendum (thanks to Iker): If the series switch is engaged when the neck pickup is selected, there will be no output at all. It’ll essentially act like a kill switch because there’s nothing else active for it to be in series with. You can decide and tell your customer if this is a feature or a bug. 😄

[iker elorriaga ieL]

Definetely a feature! A totally intentional feature, of course. 😉