SHS Wiring Ideas / Request

[Yogi B]

Since I'm currently doing some minor modifications & repairs to my other guitars, I'm aiming to strike while the (soldering) iron is hot and finally get around to doing something with a Strat copy that's been sitting in an unplayable state for at least a year. As you can guess from the thread title I've settled on the uncommon single -- humbucker -- single layout because of versatility it offers, especially regarding hum-cancelling options, maybe too versatile as I can easily think of 15 combinations that I'd like to get out of it, 13 of which are hum-cancelling. I suppose I'd better list them then...

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In no real order, only grouped into arbitrary categories, and numbered for convenience. Oh, and to be explicit "Mb" represents the bridge-most coil of the humbucker which is RW/RP with respect to the bridge, contrariwise for "Mn". Also I'm using "&" and "|" for series and parallel respectively with "~" for reverse phase.

First off the regular Strat positions (almost)
01) B
02) B | Mb
03) Mb | Mn
04) Mn | N
05) N

Then the three standard 4-coil positions
06) B & Mb
07) (B & Mb) | (Mn & N)
08) Mn & N

Two outer coil positions
09) B | N
10) B & N

And some out of phase sounds
11) B & ~Mn
12) (B & ~Mn) | (~Mb & N) (middle pickups out of phase with outer pickups)
13) ~Mb & N

Finally hum-cancelling approximations of what otherwise are the only two non-hum-cancelling positions
14) B & (Mb | ~Mn)
15) N & (Mn | ~Mb)

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The obvious issue and a major source of procrastination on the project as whole is of course how to wire this lot up, after several attempts I've yet to make any meaningful progress toward a solution (I recall saying I'd soon have a thing to help with this issue, but as usual Hofstadter's law applies itself), hence my posting here for your thoughts on creating a layout with these options available as well as possible omissions (or maybe even additions) to such a scheme to make it more achievable.

[newey]

Yogi B-

Welcome Back!

Just a few random thoughts about this proposal. First, let's start at the end of your list:

Finally hum-cancelling approximations of what otherwise are the only two non-hum-cancelling positions
14) B & (Mb | !Mn)
15) N & (Mn | !Mb)

If you have 3 coils, you can have only partial hum cancellation. The only "approximation" of the set-up might be with a dummy coil or some such, but with 3 coils, you won't have full hum-cancellation.

As far as ideas for the overall wiring scheme- well, essentially, what you're talking about is a 4-pickup Stratocaster. I happen to have one of those, the "4Caster"



Not exactly what you have in mind, but it might give some useful ideas. Basically, the 4Caster has 4 DPDT On-On switches to control the pickups in two "binary tree" arrangements. In this scheme, we can designate the pickups as "N", M1", "M2", and B, in that order. N combines with M2, and is controlled by 2 of the 4 switches, giving M2, N+M2, NXM2, N. The other 2 switches control B and M1 in the same fashion- each coil individually, or combined in series, or combined in parallel.

So, it sort of makes 2 widely-spaced humbuckers, N and M2, B and M1. The two pairs are then selected by a 3-way switch, giving either N and M2 or B and M1, and in the center position giving (N and M2) + (B and M1). Thus, it doesn't do series selections between the 2 "Humbuckers", but only combines the two sides in parallel.

A number of out-of-phase options could be added to such a scheme via a push/pull pot. To get the full complement of OOP selections you listed will probably require more switching.

[Yogi B]

Feb 1, 2016 23:34:48 GMT -5 newey said:

If you have 3 coils, you can have only partial hum cancellation. The only "approximation" of the set-up might be with a dummy coil or some such, but with 3 coils, you won't have full hum-cancellation.

Can we ever have more than partial hum cancellation, you can do it with any number (well, any integer greater than one) of coils, and the specific case of three coils has in fact been the topic of this recent thread

It's far to late/early for me to keep track of the probably required more switching, so I'll leave it at that for now.

[newey]

That approach will work, but involves putting the two coils of the HB OOP with each other. This will sound different (perhaps in a good way, but different nonetheless) than B X(Mb + Mn). Note that I'm using the more standard terminology, or I should say, standard around here anyway, using "x" for series and "+" for parallel.

Some further notes/thoughts:

First, Ibanez often has HSS guitars where the coils are switched sequentially, or progressively, as you want with this SHS set-up. Ibby uses a specialized 5-way switch to make this happen. You could procure one of those for the 5-way switching. Otherwise, you will need a Superswitch- but you may well need a superswitch anyway to do some of the other switching you want.

Next, this:

Then the three standard 4-coil positions
06) B & Mb
07) (B & Mb) | (Mn & N)
08) Mn & N

is essentially like Les Paul switching. Way back in the day, we had a guy who had a Strat designed to switch from "Strat mode" to "LP mode" with the flick of a switch. That diagram might serve as a starting point. It's deep in the back pages, I'll see if I can dredge it up for you.

[newey]

Found it. This uses a 4PDT as a mode switch, with a standard 5-way. Of course, your 5-way switching will be different.

guitarnuts2.proboards.com/thread/3172/hsh-switched-sss-hh

[Yogi B]

Feb 2, 2016 6:39:36 GMT -5 newey said:

standard around here anyway, using "x" for series and "+" for parallel.

My use of "&" and "|" borrows from their use as bit-wise AND and OR operators, which: are more intuitive to me; generally stand out more in a page of mathematics or code; avoid the contradictory feeling that series(= "x" = multiplication), sums (= "+" = parallel) the most commonly used attributes to describe pickups (voltage output, inductance and DC resistance); and mean I don't have to translate back and forth between "*" and "x".

That approach will work, but involves putting the two coils of the HB OOP with each other.

Yeah that's what I said, I knew "!" was a bad choice, since I usually use "~" to denote OoP anyway, I don't know why I used it (and have now edited it away).

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but you may well need a superswitch anyway to do some of the other switching you want.

Well I expected requiring at least that much if sticking to five-way switching, if not one of the 8-pole double wafer Megaswitch-Ms.

[ashcatlt]

Didn't read all of the thread, but... My Mini Strat is SHS. The B and M are RWRP from each other (I actually used the original N and M) and each is paired with its humcancelling partner from the HB on a rotary switch. So there's two DP5T rotaries - one goes N, N+M, N*M, M, Off, and the other goes Off, M, M*B, M+B, B. Then there's three DPDT mini-toggles: S/P combination of the rotaries, Invert polarity of one of them, and a kill switch. This gives almost all possible combinations of the 4 coils. It does have one gotcha in that if it's in system series, and you set one of the rotaries to Off, the whole thing goes dead, but "open and noisy" dead, rather than "shorted and silent" like the kill switch. Replacing one of the rotaries with a 4P5T should allow you to get around that, and might even fit in a full-sized strat, but it wont work in this little thing.

[Yogi B]

Okay, so I've had a bit of a brainstorm and upon the realization that I should be thinking in terms of groups of 3 positions instead of groups of 5 positions, I now reckon that I have a solution for 14/15 of the positions utilizing (only) the double-wafer Megaswitch M and a 4PDT On/Z/On switch, here's the truth table of what I'm thinking (assuming the formatting doesn't go awry, also the megaswitch ordering is subject to change):

┌───────────────────────┬──────────────────────┬─────────────┐
│ Switches              │ Output               │ Number      │
├────────────┬──────────┤                      │ From        │
│ Mode       │ Selector │                      │ Opening     │
│ Megaswitch │ 4PDT     │                      │ Post        │
├────────────┼──────────┼──────────────────────┼─────────────┤
│ LP-ish     │ Treble   │ B & Mb               │ (06)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Middle   │ B & Mb | N & Mn      │ (07)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Rhythm   │ N & Mn               │ (08)        │
├────────────┼──────────┼──────────────────────┼─────────────┤
│ OoP        │ Treble   │ B & ~Mn              │ (11)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Middle   │ Mb & ~N | ~(B & ~Mn) │ (12)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Rhythm   │ Mb & ~N              │ (13)        │
├────────────┼──────────┼──────────────────────┼─────────────┤
│ Tele       │ Treble   │ B                    │ (01)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Middle   │ N | B                │ (09)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Rhythm   │ N                    │ (05)        │
├────────────┼──────────┼──────────────────────┼─────────────┤
│ Strat-ish  │ Treble   │ Mb | B               │ (02)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Middle   │ B | Mn | N | Mb      │ (03) almost │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Rhythm   │ N | Mn               │ (04)        │
├────────────┼──────────┼──────────────────────┼─────────────┤
│ Misc       │ Treble   │ B & ~(Mn | ~Mb)      │ (14)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Middle   │ N & B                │ (10)        │
│            ├──────────┼──────────────────────┼─────────────┤
│            │ Rhythm   │ (Mn | ~Mb) & N       │ (15)        │
└────────────┴──────────┴──────────────────────┴─────────────┘
Note, it's probably possible to get that currently troublesome (03) position by using a 4P3T for the selector switch, but I think that sacrificing the humbucker in parallel for all coils in parallel is worth it for the ease of operating a toggle switch.

When I draw up a wiring diagram for review later we might find that my 8P5T wiring could be optimized to allow for it anyway.

[Yogi B]

Well It wasn't exactly going to be a simple one, but I reckon this *should* be it. I did swap the order of the modes on the Megaswtich so it's now LP, Misc, Tele, Strat, OoP from bridge to neck (as long as I've interpreted the Megaswitch's lettering correctly).

And I've just realized that swapping the left & right 'halves' of the 4PDT would probably clean up that bit of diagram a tad, but here's what I have at the moment: