hey, this is not a fight, is a friendly inquiry on both our parts, right?
Of course. I don't understand why everyone on the internet assumes that a discussion must be an argument. I
I disagree...I don't think that inverting the poles of the J is necessary, at all
IMO...the WAY to wire this is to build a straight-up stacked J, and a straight up split P...these can then be combined (or not)...like I said, 4-wires and a 3-way switch for P/parallel/J is the way to go...
A P with both facing the same direction is just fundimentally wrong. You're correct, you will get hum.
Humcancelling comes from reverse wind. But when you reverse wind, it is then necessary to apply the polarity correctly, else you'll get phase cancellation. Phase cancellation = puny sounding pickup
My point is that if you have a P with two seperate coils, the EA and DG pairs are out of phase with each other. Not a big deal.
But if you combine that with a standard J pickup, you're going to have EA in phase, and DG out of phase between the two pickups, or vice-versa.
The flipped magnets on the J is a total guess.. I don't know if, or how well it'll work.
I know my P+J sounds kind of crappy with both pickups on full, sort of weak in the bass. I think the bass strings are out of phase. The P has way more bass than the J, so it overpowers it, and doesn't sound
completely out of phase wrong, but it definitely sounds much better with either pickup soloed than it does combined.
As far as the "You're correct, you will get hum." thing goes, You have to keep in mind that with a P with a north orientation, and a J with a south orientation, you would have a humbucking effect much as you would with a badly mismatched humbucker. The hum comes from the fact that the coils aren't identical.
Hum cancellation will definitely be better with a standard set up P, and a stacked-bucker J, but I don't think the phase thing should be ignored, unless you plan on soloing a pickup all the time.
winding a J sized pickup split like a P might be an interresting way to do it, or perhaps wiring a stacked humbucking P, with both sides the same polarity (assuming you still want the stagger) Otherwise, 2 J style, or standard humbuckers make more sense. Probably the reason why that's usually how it's done.
-Nick