Which S/P Option?

[col]

Hi,

I am working on a design with limited switch options (just two DPDT switches) for a pair of humbucker-type pickups. The switches can be two- or four-pole types. I am only interested in series/parallel arrangements. Which option, likely, would be best?

The options (as I see them):

Option A:

1st switch: 4PDT to put both pairs of coils within each PUP into series or parallel.

2nd switch: DPDT to put the pair of PUPs into series or parallel with each other.


Option B:

1st switch: DPDT to put the coils of one PUP into series or parallel.

2nd switch: DPDT to put the coils of the second PUP into series or parallel.

The two PUPs would be fixed as either series or parallel with each other.


Option C:

1st switch: DPDT to put the coils of one PUP into series or parallel.

2nd switch: DPDT to put the pair of PUPs into series or parallel with each other.

The second PUP's coils would be fixed as either series or parallel.


I am leaning towards option A. However, if you think option B would be better, would the two PUPs be best in series or parallel with each other? If you think option C would be better, which PUP (neck or bridge) should have the the S/P coil switch? Or, maybe, there is an option D I have not considered. Remember, just to two toggle switches!

Thanks.

[ashcatlt]

Is there a pickup selector? Are there any pots involved here? Otherwise all of your options have both pickups on all the time.

[reTrEaD]

Oct 10, 2015 17:46:23 GMT -5 col said:

Or, maybe, there is an option D I have not considered. Remember, just to two toggle switches!

With two HBs and just two toggle switches, I would lean toward...

Option D:

Neck HB wired with its two coils in parallel
Bridge HB wired with its two coils in series

The two dpdt toggle switches would be wired together to achieve these four results:

Both pickups in parallel
Neck only
Bridge only
Both pickups in series

JMO

[newey]

RT's suggestion:

Both pickups in parallel
Neck only
Bridge only
Both pickups in series

is the classic "binary tree" wiring, and is a better idea than A, B or C. The switching is a bit futzy, but I've found one gets used to it pretty quickly.

My "option D" would be to use two DPDT On-On-On switches, to give series/parallel/off for each pickup. This can probably also be done with On-Off-On switches. This arrangement is perhaps easier to wrap one's head around, since each switch is only controlling a single pickup.

[JohnH]

I reckon Id agree with newey's Ootion D, if there are only these two toggles and no other switches. It gives 8 good simple sounds plus off

[reTrEaD]

I agree, John. I dislike switching that has an off possibility, but having 8 choices is a good thing.

[col]

Hi,

Thank you for your replies. I probably wasn't clear enough: For this exercise, I am only interested in possible P/S arrangements for a pair of pickups, using just two toggle switches. I already have single pickup options covered. So, unless I'm missing a possible P/S option, I am just looking at options A, B or C.

Thanks.

[JohnH]

Still not sure if there is another switch or switches to cover these single options, if they are on this guitar. Wed need to know in order to discuss the extra switches.

[ashcatlt]

Would also be nice to know something about the pickups. If they're about the same electronically, then it doesn't really matter which is in series and which is parallel. The filter works out the same, so option B has some redundancy and the question on option C (which pickup) is moot.

Both option A and C offer four different tones (edit - no, the math proves otherwise as mentioned below), but the difference between the extremes will be greater in option A. If you'll forgive a little bit of symbolic math where + means parallel and * means series, both will give you all four coils in series:
(1*1) * (1*1) = 4
And each pickup in local series in system parallel:
(1*1) + (1*1) = 1
Option A also has both pickup in local parallel with system series:
(1+1) * (1+1) = 1 (redundant)
And all four coils in parallel:
(1+1) + (1+1) = 0.25
Whereas C gives you one pickup parallel, the other series in system series:
(1+1) * (1*1) = 2.5
And I system parallel:
(1+1) + (1*1) = 0.4

Basically, smaller totals means quieter and brighter output. So I guess option C is the only one that gives four unique sounds, but it doesn't quite get as bright as A.

If the pickups are significantly different from one another, it starts to matter which one is in which mode, so that option B starts to make more sense and you really have to think about how you're going to wire C.

[col]

Thanks for the replies.

JohnH Single pickup options are already covered by other switching. This is part of a stealth design; this is why the switching is limited.

ashcatlt Thanks for the calculations. Of course impedances are just part of the picture (position of the pickups, and pickup types utilised in each location being the other main factors). But....

The input I seek is for a wiring design I'm working on (almost complete). It is not for a specific guitar - it is theoretical, so I'm interested in what is probably the best option for most situations (or the majority of situations, at least).

[ashcatlt]

If all of the coils are always on then all the switching does is change the filter and those calculations tell you all there is to say.

It is important to know what's going on around this because its very hard to make any of these work as plug and play modules. How this is wired will affect how that is wired and vice versa.

[col]

Hi Ash,

This is not going to be a module, and I can make the wiring work for any of the options (A, B, or C). It is about optimising the default design: which combination of two P/S switches will be best in the majority of situations.

[newey]

Well, this is still a bit cryptic, and it's not clear to me whether the individual pickups are able to be turned on/off. But if we're talking overall theory, I've never been much of a fan of having 4 coils all in series (i.e., series HBs wired togehter in series) as the sound lacks definition and is too dark, IMO. I do like HBs in parallel. So my preference would be to lose the system series/parallel in favor of individual pup series/parallel switches.

But that's simply personal preference.

Bottom line is that, with only 2 switches, you have to lose something- you can't do all series/parallel options of 4 coils, you'd need more switches for that. So it seems to me to come down to eliminating the option you would least like, and be least likely to use.

If it came down to picking whether the bridge or neck pickup should get its own series/parallel HB switch, I'd go with the switch on the bridge pup, and leave the neck as the one to be "hard-wired".

[ashcatlt]

OTOH - I'd rather have all four in series than all four in parallel. The series one will be darker, but it'll pound the amp hard enough to make up those harmonics via distortion. It's a really ballsy, throaty tone that works quite well for doom and sludge and stoner metal type tones. It also well a bit cleaner layered under other brighter tones to add a bit of weight without calling too much attention to itself.

Four coils in parallel can get pretty brittle, and is pretty quiet. Even though it ends up humbucking, it still compromises S/N ratio pretty bad. That extra octave (above a pair of SCs in parallel) turns into fizz pretty quick if you try to overdrive anything. It can work for cleaner tones, but I really don't use it all that often.

I still don't honestly believe that it matters much which pickup is switched internally if all of the coils are the same.

[col]

Oct 15, 2015 18:34:19 GMT -5 newey said:

Well, this is still a bit cryptic, and it's not clear to me whether the individual pickups are able to be turned on/off. But if we're talking overall theory, I've never been much of a fan of having 4 coils all in series (i.e., series HBs wired togehter in series) as the sound lacks definition and is too dark, IMO. I do like HBs in parallel. So my preference would be to lose the system series/parallel in favor of individual pup series/parallel switches.

But that's simply personal preference.

Bottom line is that, with only 2 switches, you have to lose something- you can't do all series/parallel options of 4 coils, you'd need more switches for that. So it seems to me to come down to eliminating the option you would least like, and be least likely to use.

If it came down to picking whether the bridge or neck pickup should get its own series/parallel HB switch, I'd go with the switch on the bridge pup, and leave the neck as the one to be "hard-wired".

Oct 16, 2015 7:54:13 GMT -5 ashcatlt said:

OTOH - I'd rather have all four in series than all four in parallel. The series one will be darker, but it'll pound the amp hard enough to make up those harmonics via distortion. It's a really ballsy, throaty tone that works quite well for doom and sludge and stoner metal type tones. It also well a bit cleaner layered under other brighter tones to add a bit of weight without calling too much attention to itself.

Four coils in parallel can get pretty brittle, and is pretty quiet. Even though it ends up humbucking, it still compromises S/N ratio pretty bad. That extra octave (above a pair of SCs in parallel) turns into fizz pretty quick if you try to overdrive anything. It can work for cleaner tones, but I really don't use it all that often.

I still don't honestly believe that it matters much which pickup is switched internally if all of the coils are the same.

What I get from these two posts: try to offer a broad a tonal range as possible. Thanks guys. I think I have enough to go forward in my decision.

[JohnH]

I'm beginning to understand what this thread is about. Its not about actually how to wire various options, since we don't know about the rest of the wiring and switching. Its about what are the good switch functions and combos for combined settings of two pickups.

I've got a few guitars where I can combine things in more ways than necessary, and there are certain types of combos that I find I like:

Two coils in phase, series or parallel, with one from each pickup
Parallel wiring of a bridge Hb, but with Neck Hb's I prefer a single coil

For what I play, I never want more than two coils in series, except very occasionally a bridge Hb in series with a neck single out of phase, but I no longer add phase switches to my guitars.

I think your option A is pretty good, but for a D, Id suggest the following, given an assumption that you also have a standard toggle switch as main pickup selector:

1 a 'Cross over' switch. Its a dpdt that takes the ground-side coil of each hum bucker and swaps them, so instead of full bridge and full neck, you get inner coils and outer coils, each in series, selected with eth main toggle

2, a 4pdt to turn each humbucker locally from series to parallel. If switch 1 is also activated, you get the inner or outer coils in parallel. As an alternative, Id consider a dpdt that just cuts each pickup to single, but the bridge will be cut via a cap to keep more thickness.

[col]

Hi JohnH,

Thank you for the reply. All interesting options, but I have most of them covered. I'm just working on hum-cancelling options (in my grand scheme), so I would not include three coils configurations. But your comments do confirm some of my own thoughts.

Thanks.

[col]

I also wish to add - to save any confusion - there might be a possible commercial application to this. This is why I've been somewhat vague, and asked only about what you think might be the better S/P options; not for help with logical problems, schematics, wiring, etc.

Again, thanks for the feedback.