Brian May Series/parallel switching SSS (3x 2P2T + 1x 4P2T)

[dylanhunt]

This is my first post and I appreciate all the time and energy the administrators and other contributors have given to this forum.  I have learned a lot by reading posts on this forum over the last few months, during which I have been trying to solve what I thought was a simpler problem than it turned out to be.  Apologies in advance and please forgive me if I am duplicating an existing post.  I have searched and searched (here and on other forums) and haven't found a close enough match to solve my problem, but can't claim to have done an exhaustive search.  The helpful results I have found involve variations on a common theme (Brian May's Red Special), but I could not apply the results as I found them and was not sure how to modify many of them.  These included posts involving a minimalist description without a schematic or other drawing, use of standard strat switches rather than individual switches, two switches rather than one for each pickup, two pickups rather than the complications of three, or an even more complicated arrangement than I imagined.

I wish I could build a model before actually soldering my "solution" together.  My original goal was to see if anyone could blindly--without me saying what I am trying to accomplish--tell me without knowing what I'm trying to do, what you think an application of this schematic for switching would do.  After some thought, I realized that just sounds like I am being coy, rather than scientific.  It's probably obvious what I am trying to do anyway with the schematic.  I am also hoping that members could tell me if the following schematic would fail (would short out, is likely to have ground hum, lacks continuity somewhere, is illegible).

My constraints for changing pickup settings on an SSS arrangement are: One and only one switch per single-coil pickup, including phase-switching on at least two pickups, and one and only one switch for switching between series and parallel circuits.  I think it can be done with three DPDT (on/OFF/on) toggle switches and a single 4PDT (on/on) slider switch.  Unfortunately, I know very little about electrical engineering and have no way of knowing if this result represents the complete logic required for what I want.  Many many thanks in advance for any help you can offer.

[newey]

dylanhunt-

Hello and Welcome to G-Nutz2!

Sept 13, 2021 10:45:36 GMT -5 dylanhunt said:

I think it can be done with three DPDT (on/OFF/on) toggle switches and a single 4PDT (on/on) slider switch.

Assuming this is the arrangement represented by your schematic (IOW, each pickups' phase switch is a "center off" type which will disconnect that pickup entirely), then your schematic won't work because turning either the middle pickup or the bridge pickup "off" when the 4PDT switch is set to the series setting will break the "series chain". So, in series, if the neck pickup is "on" but the middle or bridge pickup is turned "Off" (i.e., center position on its switch), then you would have no sound from the neck pickup. If the middle pickup is "On" but the bridge is off, same thing, no sound.

If there's a way to do what you want with only one switch per pickup, I'm not seeing it myself. Certainly not with On-Off-On switches, anyway. Maybe someone else has some better ideas for you. Essentially, with series switching, you can't just turn a pickup off, you have to bypass that pickup in the series chain. With the On-Off-On switches, you are using both the "active" ends of those switches for your phase switching, meaning there's no other switching available to bypass the pickups when in series mode.

[dylanhunt]

Thank you so much, newey, for your explicit critique!  I see now that I repeated a pattern (I can see now is) represented in Replies #45-49 of guitarnuts2.proboards.com/thread/4641?page=2  Your point (made by John H) was not explicit in that discussion (and it probably appears, implictly, in other discussions and I have just missed it over and over again.). Maybe my thread is a good place to exhibit the mistake and the explicit critique of it. I had seen someone claim that you could do this, but without elaborating on how, and I ran with that.

I did wonder at some point why the son of an engineer who could and did build his family's television wouldn't have simply used one 2P2T switch with a center-off position for each pickup instead of two on/off 2P2T switches.  I concluded that the component simply must not have been available to Brian May's father in 1960's Britain.  Now, that seems silly: If the components of a television and other household appliances were available, a center-off DPDT probably would be too.  I will now go back and look at the options, deciding between:

• John H's tonemonster schematic option (https://guitarnuts2.proboards.com/thread/3121), or
  
• your BM+ option [N+M, B+M, and (B*N)+M, with dead solo Middle in parallel] (https://guitarnuts2.proboards.com/thread/4650).

  
Thank you for saving me loads of time I would have had to spend debugging!

[newey]

The thread that you linked to was Killheart's discussion thread, for which JohnH supplied a diagram. After we solved Killheart's scheme, JohnH posted the design in the Schematics section:

guitarnuts2.proboards.com/thread/4855/brian-series-parallel-switching-sss

I assumed you had seen that one, as opposed to the "discussion thread". In any event, JohnH mentions the need to bypass the unused coils in the first post there. Later, the discussion turned to whether one could have the phase switches and pickup on/off on a single switch- which can be done, but requires 4PDT On-Off-On switches for each pickup, for the reason I stated above. 4PDT toggle switches are available but they are pretty bib and you may have trouble fitting 4 of them (one for each pickup, plus a series/parallel 4PDT) into your guitar's cavity.

I see that you also found my BM scheme, which doesn't give all the parallel options, but also doesn't require a 4-pole switch.

[dylanhunt]

Thanks again newey!  Do you happen to have a reference for that part of the discussion you mentioned about 3x 4P2T switches (each pickup)?  Also, did you mean "on/on/on" or "on/off/on"? I only found these references, and it looks like I'm out of luck as far as a schematic or wiring diagram goes:

guitarnuts2.proboards.com/thread/4641/brian-red-special-series-parallel?page=2&scrollTo=45203

Reply #46 posted May 22, 2010 at 5:20pm by JohnH
Hi gd, and welcome to GN2. Thank you for your interest in the enhanced Brian May design.
...  3. You could build my full BM design, combining the phase and on/off, but each switch is now a 4pdt on/on/on, which are the same size as the two position 4pdts (ie twice as large), and are rather expensive. Each pickup switch would have three positions, off, on out of phase, on. I'm not sure if all those wide switches will fit well in a Strat however.

guitarnuts2.proboards.com/thread/4855/brian-series-parallel-switching-sss
Reply #2 posted Jul 14, 2010 at 4:58pm by JohnH
Hi Andrew - Sorry i missed this post, but have seen your todays one. I believe you can take the diagram above, and combine the on/off and the phase switches into 4pdt on.on.on switches - just gotta be clever with which poles to use on those toggles, eg 1 and 3 for on/off. 2 and 4 for phase

Maybe you were referring to the first one.  I should have room in the cavity for a 4p2t toggle.  I will have to do some drilling (currently, there are two holes for the V+T pots, and a third hole for a toggle).  I wouldn't want to add more than two more holes for the two additional toggles. Thanks!  

[JohnH]

Hi Dylan

I think you have found all our main references above, except that there has been the scheme with four four-pole toggles, using three position on-on-on ones for the pickup selectors. The theory is good, but its a wiring tangle! Its similar to a condensation of my version - maybe we can find it, it was quite a few years ago........

[JohnH]

......see this thread:

guitarnuts2.proboards.com/thread/5118/diagram-sss-series-para

[dylanhunt]

Thanks JohnH for tracking down the 4-switch solution of Andrew Roberts!  I had seen that discussion too, but forgot about it: until now was missing something (context? conceptual connections?) to make that thread comprehensible.  I think doing the work above and understanding the conflict between a center-off 2P2T switch and a series/parallel option has been a little like learning the language that and other discussions are written in.  Many thanks to newey and you for openining my eyes.  Couldn't ask for a better welcome!

I'll add the thread started by UnklMickey (is he still around?), though it is referenced in the 5118-thread you linked: guitarnuts2.proboards.com/thread/3160
For the abstruse brilliance of his discussion, I'd suggest he change his handle to "UnklWittgey" after Wittgenstein, the inventor of the truth table and other logical innovations.

I'm working on a bestiary or catalog of the options in a table/chart form.  Right now, I'm focusing on 3(+1) options, but I'm making notes for solutions using two switches per pickup.  Here's a start (it's just an in-progress sample and not really ready for viewing):

[JohnH]

Hi Dylan

Sadly UnklMickey disappeared from GN2 not long after the threads of his that you have seen. We don't know what happened to him, but we greatly valued and enjoyed his contributions and seek to keep them available where we can.

You seem like an inquisitive chap who enjoys logic and puzzles. The nice thing about these complex schemes is that they exist within a defined universe bounded by the available switches, pots and pickups, and within that realm there are endless possibilities, kind of like a chess game. But unlike just a game or a puzzle, when you have finished, you can build your design and rock-out with it!

When thinking about comparison of alternatives, you can set your own rules for evaluation. I like to consider the following, in addition to just how wide of a range of tones is available:

How easy is it to find the most basic and common settings? and how easy is it to make key changes with minimal switch moves?
Does each switch have a clear function? and if it makes a change to one combo, does it mess up another one that is often needed?
Are there any quirky dead spots or excessively noisy settings?
Are there a lot of redundant settings?, or settings that sound almost the same?
How fiddly are the switches to use ? (eg, rotaries can be stiff, 3-position toggles need some care to move to the middle position)

Electrically, we keep learning. We try not to have coils 'hanging from hot', ie not active but still connected to the output at one end, which can add a small buzz, unless shielded. Also, shunting of coils can add damping. We have now seen through testing how this happens in a humbucker if one coil is shunted to make a single coil - it still works though. I don't think its such an issue with shunting single-coil pickups or whole pickups though.

Good luck with your investigations.

[dylanhunt]

I do like logic puzzles, JohnH, but in moderation.  I did feel like I should be able to solve all on my own the problem of switching between parallel and series circuits with three loads (at least, to the point I did with my schematic, complicated as it was with off switches and phasing), but I was never opposed to looking up the answer at the back of the book, if only there were such a book (never found it, even for a problem using lamps instead of pickups).  All the notes I'm making here are all simply a matter of practicality.  I don't want to use more than is necessary, and I'm looking at the options of what will work because I need to know that the minimum set of parts I have in mind will actually be sufficient.

Apart from routing the three SSS cavities, I'm drilling two and only two holes into the body of my Aria Pro II Cardinal CS-300, which already has one toggle hole, one volume control hole, and one tone control hole.  I removed the single humbucker and will be using its cavity for the series/parallel rocker (4PDT, on/on/on) switch and an on-board battery-powered treble booster with an on/off push button.  I should have all of the switches I need by this weekend.  So, as soon as I do my remaining homework (draw up a schematic of Andrew Roberts' version of your design or YogiB's version of AR's design, and then redraw the wiring diagram according to the proper orientation of my switches to see if it matches the original), I'll start wiring it up.

I've been a little worried about not seeing any real-world testing of the design.  Looks like AR's brother used AR's build, but I don't think AR reported back on whether there were any problems with the switching related to the imperfections Yogi B found.  That had to do with AR's hybrid/Easter-egg position on the series/parallel switch ({BxM}+N).  My impression is that nobody has been able to eliminate that issue without going higher than a 4PDT, though YogiB did modify it to something like Gibson's S-1 lead switch (solo pickup).  That "issue" is not a deal breaker for me personally as it is triggered when the middle pickup is off.  One of the consequences of implementing a transparent and intuitive switching arrangement (incl., on/off switches for each pickup) is that opaque, counter-intuitive problems are not genuine problems, even if they are undesirable in the abstract.  In other words, you shouldn't expect your Bridge-in-series-with-Middle setting to work if your Middle pickup is off (Solution: Turn the flipping pickup on!). 

This extremely helpful account of solderburn's journey building it and all of the support he had from GN2 debugging it is the only real-world testing account I have found and it's a treasure: 
guitarnuts2.proboards.com/thread/8420/jag-pus-series-parallel-phase?page=2&scrollTo=87713

Companies would charge hundreds of dollars for the kind of support GN2 members provided for solderburn's build (and others), and now I benefit from the time he took to post his experiences (and the time others others gave to reply to him).  You guys should be so proud of the amazing resource GN2 is.

[JohnH]

For me, id say that extra hybrid middle position is a setting-too-far, a complication that creates a sound that probably isn't any more useful than the others. I would just do a 2 position switch there and avoid the issues.

It looks like I checked the previous version though, dated Jul 17, 2010

[mark3796]

I can verify that this will work if you use 2P3T switches, like the C&K 7000 series. They are on, on, on switches. You can wire them to bypass any pickup in the middle position.

www.ckswitches.com/products/switches/product-details/Rocker/7000/?Group_Circuit=DP&Switch_Function=On-On-On&Circuit=DP3T

In the diagram below, the switch contacts are in red. The first switch is in the off (middle) position to show how the circuit bypasses that pickup.

This gives all possible combinations of series, parallel and phase with no dead spots. It's also easy to understand. You have one switch to switch between series and parallel, and one switch for each pickup, which can be down (normal phase), middle (off), or up (phase reverse). Of course, if all switches are either up or down, they are in the same phase. I've had this for years and I love it. Only problem is there is a bit of hum.

[JohnH]

Hi Mark and welcome to GN2 and thanks for your diagram.

I'm not seeing how, in parallel mode,and you have a pickup or two off, it doesn't shunt from ground to hot, cutting out the signal?

[mark3796]

Hi John,

I agree, looking at it that way, it shouldn't work. I'm sorry, I can't explain that. It would require someone much cleverer than me. All I can say is that it does work. Is it because the coils in the pick ups generate the current?

[newey]

The C & K website you link to is just a list of all their On-On-On switches, which they describe as "DP3T" switches. To avoid confusion for anyone who sees this, note that technically the switch is a "DPDT On-On-On". The center position is not a third "throw" as a "throw" implies that a distinct set of connections is being made, not just a reordering of the connections already made.

There are, however, switches that are DP3T, but these are slide switches, not toggles.

[Jaga]

Oct 7, 2021 5:38:20 GMT -5 newey said:

There are, however, switches that are DP3T, but these are slide switches, not toggles.

AFAIK they are not technically DP3T switches since 1st and 3rd throws don't have common terminals. I like Yogi B representation that it's rather «a chain of three DPSTs in which only one is ever closed». It can be however used as SP3T (not DP3T though). Picture posted by reTrEaD in the same thread:

[mark3796]

Here's how it looks. Sorry for the confusion. There seems to be some different names for the switches. I bought them DPDT On, on, on. But when I went to find them on the C&K site, they refer to them DP3T. I guess that's because they are 3 position, not to be confused with two position.

And, yes, I made the scratch plate. It was a bit of an experiment, and I wanted to keep the original deck in case it didn't work. I designed the circuit myself. The way I was thinking was that the pickups were generating current. In my simple way of thinking about it, I was thinking of them as AA batteries. Anyway, it does work. I have series/parallel and each pick up can be "+", off, or "-", if that makes sense.

[Jaga]

These switches look really nice with black pickups and knobs and on such an acid pickguard. And I like them much better than 5-way strat switch

I don't think that 3-way DPDT On-On-On switch should be called as DP3T, but that's not your fault

[newey]

Oct 7, 2021 17:55:08 GMT -5 Jaga said:

I don't think that 3-way DPDT On-On-On switch should be called as DP3T, but that's not your fault

As noted, C&K has it wrong; if one is looking for the switch at Mouser or other sites, search for DPDT On-On-On.

The DP3T slide switch is three throws, by the standard definition of a "throw" as meaning a discete set of connections. The fact that a slide switch doesn't have a "common" lug is irrelevant, as having a common lug is no part of the definition.

[dylanhunt]

Oct 6, 2021 16:26:03 GMT -5 mark3796 said:

I can verify that this will work if you use 2P3T switches, like the C&K 7000 series. They are on, on, on switches. You can wire them to bypass any pickup in the middle position.

www.ckswitches.com/products/switches/product-details/Rocker/7000/?Group_Circuit=DP&Switch_Function=On-On-On&Circuit=DP3T

In the diagram below, the switch contacts are in red. The first switch is in the off (middle) position to show how the circuit bypasses that pickup.

This gives all possible combinations of series, parallel and phase with no dead spots. It's also easy to understand. You have one switch to switch between series and parallel, and one switch for each pickup, which can be down (normal phase), middle (off), or up (phase reverse). Of course, if all switches are either up or down, they are in the same phase. I've had this for years and I love it. Only problem is there is a bit of hum.

What a great discussion your post prompted!  For me, as of October 5th, it is too late for my Brian May sound-alike build, but I will definitely look it over for use in a Jag mod.  Are you able to record the resistance readings for some of the positions to verify the series positions are really series, etc.?
 

[dylanhunt]

The good news on my end is that Yogi B's redesign:
guitarnuts2.proboards.com/post/87266/thread
guitarnuts2.proboards.com/thread/8420/jag-pus-series-parallel-phase?page=2&scrollTo=87713

of aroberts8089's design:
guitarnuts2.proboards.com/post/47054/thread

is a winner in my books. The center position on the series/x/parallel switch provides a Middle and Bridge in series, with the Neck pickup in parallel.  For some reason, I had been wishing the Easter-egg position was two pickups in parallel with a third in series instead, but I actually don't know how to understand the difference between the two in theory (probably if I heard them).  What I have now is great.  That center position, with all pickups on, sounds better than any other setting for strumming, and when the treble boost goes on, it's a fantastic sound for lead.

It wasn't exactly smooth sailing since it has been a couple decades since I last did any serious soldering.  I had to redo the first toggle switch all over again, but after I did that, everything worked.

The Body: A 1981 Aria Pro II Cardinal CS-300 routed for a SSS configuration.

Under the Hood: Three of Adrian Turner's (of Adeson) exact replicas of the mid-60s Burns Tri-Sonic pickups (Guyton version) on Brian May's Red Special.

Features in the Cockpit: Onboard treble boost at the push of a button; rocker switch for series and parallel circuits; and single-toggle switching for each pickup (on, reverse phase, and off).

Here are the recordings for resistance (Before finishing/After finishing all wiring), while the settings using the reverse phase positions gave me the exact same readings as normal phase positions:

in KiloOhms	SERIES ON	EXTRA ON	PARALLEL ON
N	7.14/6.71	0.38/0.37	7.14/6.71
M	7.50/7.03	7.50/7.02	7.50/7.02
B	7.22/6.78	7.22/6.78	7.22/6.78
NM	14.64/12.83	3.66/3.55	3.66/3.55
NB	14.37/12.62	3.59/3.49	3.59/3.49
MB	14.73/12.89	14.73/12.9	3.68/3.58
NMB	21.80/17.98	4.81/4.62	2.43/2.39

BEFORE




AFTER









   

[dylanhunt]

Oct 6, 2021 16:26:03 GMT -5 mark3796 said:

I can verify that this will work if you use 2P3T switches, like the C&K 7000 series. They are on, on, on switches. You can wire them to bypass any pickup in the middle position.

www.ckswitches.com/products/switches/product-details/Rocker/7000/?Group_Circuit=DP&Switch_Function=On-On-On&Circuit=DP3T

In the diagram below, the switch contacts are in red. The first switch is in the off (middle) position to show how the circuit bypasses that pickup.

This gives all possible combinations of series, parallel and phase with no dead spots. It's also easy to understand. You have one switch to switch between series and parallel, and one switch for each pickup, which can be down (normal phase), middle (off), or up (phase reverse). Of course, if all switches are either up or down, they are in the same phase. I've had this for years and I love it. Only problem is there is a bit of hum.

If I'm reading this correctly, then my schematic at the top of this thread is equivalent or identical to your (mark3796) schematic. The only difference is that my schematic does not specify pickup switches with on-on-on configuration. I made the mistake of thinking it would work with on-off-on switch configurations. So, if yours works and doesn't have significant problems (not sure what threshhold applies here--dead spots would be a definite problem; hanging from hot, maybe or maybe not), then this would need to be added to the GN2 library. I went with four 4P2T switches instead of three 2P2T+ one 4P2T switches because I had the impression that the latter was impossible. Several people with clear practical knowledge on GN2 said so. I'm happy with the solution I used (four 4P2T) because I got a great bonus setting you can't get with yours (three 2P2T+ one 4P2T), but your solution needs to be recognized if it works. I'll try to add my (dis/)confirmation to it in the near future, but I think I'm going to have to model-build it (pre-solder) to verify to my satisfaction.

[Jaga]

Oct 10, 2021 14:46:04 GMT -5 newey said:

As noted, C&K has it wrong; if one is looking for the switch at Mouser or other sites, search for DPDT On-On-On.

The DP3T slide switch is three throws, by the standard definition of a "throw" as meaning a discete set of connections. The fact that a slide switch doesn't have a "common" lug is irrelevant, as having a common lug is no part of the definition.

The question is what is definition? I like this one (not sure if it is a trusted source though):
en.wikipedia.org/wiki/Switch#Toggle_switch
web.archive.org/web/20110423212637/http://www.herley.com/index.cfm?act=app_notes¬es=switches

The terms pole and throw are also used to describe switch contact variations. The number of "poles" is the number of electrically separate switches which are controlled by a single physical actuator. For example, a "2-pole" switch has two separate, parallel sets of contacts that open and close in unison via the same mechanism. The number of "throws" is the number of separate wiring path choices other than "open" that the switch can adopt for each pole. A single-throw switch has one pair of contacts that can either be closed or open. A double-throw switch has a contact that can be connected to either of two other contacts, a triple-throw has a contact which can be connected to one of three other contacts, etc.

[dylanhunt]

Maybe someone could start a separate thread to talk about terminology (2P3T, 2P2T, two poles with three positions, etc.).  I'm hoping that this thread could focus on getting a three single-coil guitar to work with on/off/oop switching for each pickup and serial+parallel switching, preferably how to do that with a two-pole switch for each pickup, or whatever the minimum number of poles is above two, assuming two-pole switches won't work.  It looks like our assumptions about that were wrong.  Two poles seem to be enough. 

[newey]

Oct 12, 2021 15:51:58 GMT -5 dylanhunt said:

I'm hoping that this thread could focus on getting a three single-coil guitar to work with on/off/oop

Sorry, wasn't meaning to hijack but I guess I did . . .

[dylanhunt]

No worries, newey.  I was just bothered that the lede got buried and only one person commented on the main point of mark3796's post (Actually, I don't understand JohnH's objection about shunting and would like to.  It remains a big mystery to me how to understand directionality/polarity in an AC circuit).  But anyway, this is really, really big news and satisfies my motivation for this thread: Apparently, with a slight clarification/modification, my schematic works and mark3796 tested it when he designed it himself long before I came up with the schematic.  It would be great if we could get secondary confirmation.

After all, 2P2T switches with on/on/on capability are slightly harder to find (in the States) than 2P2T switches with on/off/on capability, but 4P2T switches are much harder to find, cost considerably more, and are an absolute bear to solder.  If you can add a serial/parallel option to Red Special wiring, using in total only (3) 2P2T + (1) 4P2T that is huge news.  Some version of the schematic should be available on the schematics section of this website.  Alternatively, if there are problems with it, it would be great to hear what those are (and even then, it might still be an option many would like to know about).

[JohnH]

Oct 13, 2021 14:04:07 GMT -5 dylanhunt said:

No worries, newey.  I was just bothered that the lede got buried and only one person commented on the main point of mark3796's post (Actually, I don't understand JohnH's objection about shunting and would like to..

I'll try to clarify what I saw:

On Marks diagram, the left pickup is set in the middle off position and the other two are switched on. If we trace the connections from the volume pot via the left switch and the main four-pole switch, we arrive at ground without going through any pickups, see the green line.

If the hot connection at the volume pot is directly connected to ground in this way, then in this setting, no signal can escape and there is no sound.

[dylanhunt]

Oct 14, 2021 21:24:34 GMT -5 JohnH said:

Oct 13, 2021 14:04:07 GMT -5 dylanhunt said:

No worries, newey.  I was just bothered that the lede got buried and only one person commented on the main point of mark3796's post (Actually, I don't understand JohnH's objection about shunting and would like to..

...If the hot connection at the volume pot is directly connected to ground in this way, then in this setting, no signal can escape and there is no sound.

Thanks for explaining JohnH!  At the risk of showing my ignorance (or can I say that I am playing Devil's advocate to sound sophisticated rather than naive?)... My view would be that there is no signal along the green line, no hot connection at all... unless you're saying that it would short out the signal coming from the other pickups.  The green line would have no signal because the leftmost pickup doesn't involve a closed circuit.  Perhaps the only circuits that count would be the ones encompassing the pickups, where the signal(s) is/are generated.  So, if the middle and rightmost pickups have a closed circuit from positive on the output jack to ground on output jack, then there should be a sound (from the amp) made up of the signal of those two pickups (and only those two pickups, but affected by the variable resistor(s), voltage divider(s), and whatnot in the circuit along the way).

If you're saying that the green path would short out the signal coming from the middle and rightmost pickups, and if it in fact does not do that, I wonder if that green path is the path of greatest resistance (though it might still draw some current) and the path(s) of least resistance is the intended path(s); in other words, the route directly to the pots (rather than the one back through the leftmost switch) and out through the output jack.

[JohnH]

All the signal coming from the right and centre pickups trying to get to the output will instead go straight to ground through the green path of zero resistance, and none will go out to the amp.


If this is not true, then there are major problems with the last 200 years of electrical engineering, plus everything I've learnt in the last 5 decades!

[dylanhunt]

It sounds like the view is that the signal, for the pickup(s) that is on, should lead (after the individual switche(es) and the serial/parallel switch) through the volume and tone pots, but then through the off switch(es), then through the parallel switch again and out to ground only.  It also sounds like the view is that this path is zero resistance relative to the "intended" path.  By contrast, the naive intention is that, after moving through the individual switch(es) and the serial/parallel switch, the signal for any operating pickup would lead through the volume and tone pots and then to either the hot or ground connections of the output jack.

I know next to nothing about these electrical engineering issues, so apologies for my ignorance... Does it matter that the signal is generated by inductors (as opposed to being mains wiring) or, at the same time, that the current is alternating somewhere around 200 cycles per second, give or take?  Or is it more relevant that the ground we're talking about is a "ground" in a guitar circuit?  Or does it matter which concept is accurate: a total instantaneous, completed circuit where the circuit that has the least resistance is the only/most important one, versus envisioning movement along a path that occurs over time rather than instantaneously?  My intuitions are not what I would call informed on any of these topics.  My meager understanding lets me imagine that the current is flipping back and forth so many times each second and that the decision of which wire is the high potential ("hot") and which is the low potential wire becomes an arbitrary decision (on a RWRP pickup, it only matters that the hot wire is opposite relative to the other pickup(s), and it doesn't matter what we call the matching lead on the RWRP pickup as long as it is the opposite of the matching lead on the other pickups).  I realize this isn't an engineering class, so no one should feel any obligation to fix my misunderstandings.  These are just questions I am wrestling with.

I'm probably going to have to build a "working" model of this circuit and see if it really does work, but I probably still won't understand why it does or doesn't. Maybe there are some tests I can do, but I'm not sure what kind of measurements I would need to make to get more information about what is happening in the circuit. I have a student-level oscilloscope (Digilent), but haven't been able to figure out how to use it yet, even for testing a pot, let alone a pickup, or even more intimidating: signal analysis.