The subject of this thread is both my goal and the title of a Stew Mac resource that feels to me like it's missing some crucial pieces of information. I figured I'd go through it here to see if anyone could help me fill in the gaps. As I'm beginning to plan the wiring for my first build, it'd be easy enough for me to reverse-engineer some online schematics and trial-and-error my way through it, but I want to actually know why it all works, not just get it working. Here goes:
How a magnetic pickup works This section seems pretty comprehensive when it comes to the internal workings of a pickup, but it doesn't really tell you anything about actually wiring them. The humbucker phase chart is interesting, but how do you actually connect wires to go about reversing the phase on one coil, or wiring the two coils in parallel? How do you split the coils? And why do these processes work this way? Each coil has a start and a finish, so I'd guess wiring a finish to a finish would reverse the direction of a coil and, thus, invert the phasing. That seems intuitive enough. Wiring in parallel would just have the finishes each going somewhere else (like a volume pot) instead of one going to the other's start? I can intuit a lot here, but nothing's really explained.
What is a potentiometer and how does it work? This section was pretty unclear when I first read it, but reading the next two sections cleared it up for me. The sweeper outputs a signal with resistance based on the knob's position, right?
How is a volume pot wired? I'm not really sure what the jazz bass short-circuiting example is getting at, but otherwise this is pretty clear. If the pickup were wired directly to the output jack, with no volume pot, how would that affect tone, since a higher resistance pot prevents loss of upper frequencies? Would it be the equivalent of a really high or really low resistance pot? I'm guessing high, as pickups are high impedance?
What is a capacitor and how does it work? There's no difference between a tone pot and a volume pot, right? The tone pot just has a cap in the mix? As for the cap itself, when it says "the higher the value of the cap, the more upper frequencies are allowed to travel through it", does it mean a higher value will result in more upper frequencies going to ground or going to the amp? I guess I'm just not sure how exactly the cap interfaces with the pot. For volume, I understand why higher resistance would yield an overall brighter tone, but is the highest value of a tone cap always the "true" output of the pickup, or is the choice of cap somehow brightening or darkening your tone at its highest setting?
Selector Switches There's really no explanation here to indicate why things are wired the way they are, but I kind of hate selector switches, and will probably always use a Jaguar-esque system for my guitars' pickup selectors, so this isn't a big priority for me, but I guess I should still figure it out.
Mini toggle switch basics and push-pull pot basics I understand the idea, but I don't know if I understand the diagrams. I assume the black dots are the poles (terminology?) that are active in that position, but are there specific inputs and outputs, or do you just have four connection points to do whatever you want with? SPDT means one row instead of two? SPST would I guess mean each position of the switch would only correspond to one pole? Is that even useful? Is there a DPST? Is there any disadvantage to using a DPDT switch when SPDT would have done? Or, in other words, can I leave poles unused without causing problems?
Output Jacks I have no questions. This seems basic enough.
Grounding and Shielding At the risk of sounding like an idiot, I understand the importance of grounding, but I don't really know what it is. Does connecting the wire to any piece of independent metal get the job done? You just need something conductive that's not part of the circuit?
Understanding impedance and impedance matching This doesn't seem to explain almost anything to me, but a lifetime of amp usage has armed me with some understanding of impedance and associated math.
If anyone can help me fill in any of these gaps, I'd appreciate it! Hopefully this can serve as a resource for other wiring newbies down the road.