2HB Series Switch

[garyb]

It has been awile since I posted here. I went from Mike Richardson Strat wiring into modifying my Valve Junior. I had a P-Rails in my Les Paul in the interim but am now moving back to a Pearly Gates in the bridge position. The guitar has a DiMarzio 2 wire PAF (circa 1979) in the neck which goes through a push pull to do phase. The plan for the PG is to do an on-on-on switch to do series/split/parallel. I have another push pull in there and was looking for one more sound and thought that running the 2 humbuckers in series may be useful. Everything else here is pretty standard Les Paul type wiring as far as 3 way switch, 2v, 2t.

The question is does 2 humbuckers in series produce a usefully different tone from the 2 pick ups in parallel and is there a relatively easy way to add in this tone or is this a complete rewire upgrade?
Thanks

[gfxbss]

Gary,

Regarding if there would be a usefully different tone, that is very subjective. I personally think so, but I am sure you can find plenty of people who disagree. Usually when in series the overall sound is a little hotter.

its explained here.



also, as far as how to wire it....
www.guitarelectronics.zoovy.com/category/wiringresources.1wiringdiagrams.humbuckerwiringmods/

HTH

Tyler

[garyb]

Thanks Tyler for the input!

I realized after posting that I was basically doing a modified Jimmy Page solution here with the neck pick up doing a little less as it is only a 2 wire pickup. I know that I could make it a 4 wire if I wanted to tear it apart, but I will leave that for another day. The sad part is that I have been looking at the guitarelectronics site for a guide on the series/split/parallel and didn't even realize that the series/parallel pick up set up was there as well.

The one thing that does have me confused when looking at JP wiring is that the hot wires from the pick up selector are going to the outside lug of the volume pots rather than the center. Not really sure why this changes here. It is done this way at guitarelectronics and seymourduncan.com.

I will post my planned set up for review if I can get a decent drawing.
GB

[gfxbss]

GB,

Usually you do go from the Pup selector to an outer lug. the inner lug goes to the output, and the other outer lug is usually grounded.

Tyler

[ChrisK]

....as it is only a 2 wire pickup. I know that I could make it a 4 wire if I wanted to tear it apart....

I would be careful about doing so since this is (now) a vintage pickup pushing 30 years old. It's from the early days of the "boo-teak" pickup industry and will be worth far more "unbutchered" when these things become collectible. Also, the chances are that the patient will not recover from the surgery.

Buy a new 4-wire pickup for the neck, the SD Jazz is nice.

The one thing that does have me confused when looking at JP wiring is that the hot wires from the pick up selector are going to the outside lug of the volume pots rather than the center.

I will restate this in signal flow terms that the wires from the outside lug of the volume pots are going to the pick up selector. This is to avoid one volume pot set to off from shorting both pickups when the 3-way switch is in the "both" position.

This is usually only an issue for folk that fail to understand that if you want one volume pot set to off (uh, that pickup is really off), use the correct switch position (which is not the middle/both one).


(Now don't tell anyone, but if one has the wipers of the volume pots connected to the selector switch and wants to use only one pickup and the other pickup's volume pot IS turned fully off, the 3-way selector switch can be used as a, uh, shorting kill switch in two out of three positions. Unfortunately, if the end terminals of the volume pots are connected to the selector switch and the other pickup's volume pot IS turned fully off, the 3-way selector switch can be used as an opening kill switch in only one out of three positions.) ;D ;D

[garyb]

Hey ChrisK! Thanks for the reply.
I agree with you and wouldn't really mess with the Dmz PAF. It is certainly not the original, but they were pretty good at that time and the age hasn't hurt it any. I also have a Dual Sound/Super D that was his original room mate. It was the whole Ace Freehly thing at the time, but I don think that was one of the first 4 wire pickups. That one is cool but I was looking for something in a A2 magnet rather than ceramic. I won't let it go either though because it was a big part of my guitar history.

So is the selector to the outside volume pot terminal a function of the parallel/series switch? I don't know that I have seen it in other scenarios.
Thanks,
GB

[ChrisK]

So is the selector to the outside volume pot terminal a function of the parallel/series switch?

No, but to me it's half way to where it should be for series.


I have seen it many places. It's called the "reverse LP wiring" and is effected to prevent widespread confusion amongst the feeble-minded during 3-way switch positioning.

It is also used to reduce the product warranty returns from those that are convinced that "something" is defective (something is).


I am of the opinion that normal volume pot usage is to be avoided during series connection of two pickups in guitars with individual volume pots. This is because, if the volume pot is turned down, regardless of the wiper or end termanal connection to the selector, substantial series resistance is introduced into the signal chain.

I prefer to use volume pots in a ratiometric manner (3 terminal) in parallel and in a rheostatic manner (two terminal) in series.

See Series_Parallel Blend Pot w/ DPDT switch.

If you look in Fun with switches, take 1, section "E" for LP usage, you'll see how the reversed (from your perspective) LP volume wiring can be used to good effect. Volume pot "B" remains as a master ratiometric volume pot for the series chain, but volume pot "A" just shunts (gradually shorts out) the "A" pickup.

[garyb]

This comes together based on several Seymourduncan.com and guitarelectronics.com diagrams. Let me know if I am in the ball park or way out in left field.

Ignore that I put the on/on/on switch on top of the volume pot which is actually where the series parallel switch is.

Thanks,
GB

[ChrisK]

There are several problems with your design.

Before I correct them I need to know what you want the volume controls to do in series.

As I had mentioned, if you look in "Fun with switches, take 1", section "E" for LP usage, you'll see how the reversed (from your perspective) LP volume wiring can be used to good effect.

Volume pot "B" remains as a master ratiometric volume pot for the series chain, but volume pot "A" just shunts (gradually shorts out) the "A" pickup.

It's difficult to do anything else without requiring the 3-way switch to also be in a specific position for series.

[garyb]

Chris,
I guess that I don't have a huge issue knowing that series is only going to work in the middle position. Phase really works that way today. Sure you can have it on in the other positions but obviously it won't phase with itself, nor will it have any affect when only the other pick up is selected. It's a 2 pick up thing right?

I am OK with a master volume approach but I am unclear on the effect when not in series. I believe that things operate as normal in parallel but are in master/shunt mode in series If I am going to have a master volume, I probably would stick with tradition and put it on the bridge volume.

I appreciate your input and your work here on this board.
Thanks,
GB

[ChrisK]

I guess that I don't have a huge issue knowing that series is only going to work in the middle position.

The design that I have in "Fun with Switches Take 1" is a series override switch. It puts both pickups in series regardless of the 3-way switch position.

This means that you can have one pickup phase reversed while using them individually, with no apparent difference in sound of the one compared to when it is not out of phase, but when in series override, they are then out of phase. Series out of phase (soop) is much more interesting sounding that parallel out of phase (poop).

When in parallel, both volumes work only on their respective pickup.

When in series, one is a master volume and the other is a pickup shunt. Both pickups can also be shunted by their respective tone controls. This has an interesting effect in that if one pickup's tone is turned down in series, the other pickup is made brighter.


Since you want the bridge volume to be the master, it will be pickup "B" and the neck will be pickup "A". This means that the bridge will be the elevated pickup in series and the neck will be ground referenced in either mode. Having the shunting on the neck will allow you to dial in or out varying amounts of fundamental frequencies from the neck (which has fewer harmonics that the bridge) that are subtracted from the bridge in soop mode.

It will also be good that the series/parallel switch will be on the bridge/master volume; your hand will already be on the appropriate volume control.

[garyb]

OK Chris,
Let me try again. I think the blue dots are the hot side of the pickups, correct?
Thanks,
GB

[garyb]

Here is attempt 2, incorporating the volume pot mods. Let me know if I interpreted this correctly.
Thanks,
GB

[ChrisK]

I think the blue dots are the hot side of the pickups, correct?

Yep.

I'll look at your new design later. I have New Year Eve family stuff to do and I also have to write and publish a technology position paper today (I'd said that I'd do it by the end of the year).

[cynical1]

Dec 31, 2008 15:01:14 GMT -5 ChrisK said:

...and I also have to write and publish a technology position paper today (I'd said that I'd do it by the end of the year).

[garyb]

Thanks Chris! Good luck on the paper and Happy New Year to all.
GB

[ChrisK]

[garyb]

I love the smell of hot solder on new years day! Thanks Chris and Happy 2009. ;D ;D ;D ;D
GB