Post
by Embenny » Sat Oct 24, 2020 8:33 am
It doesn't actually matter which lead you use as hot vs ground, as long as you use the same one for both pickups. Flipping the leads around just reverses phase, so it's only an issue when trying to match pickups to each other.
The poles in your JM pickups are all identical in this case. Some pickups are built with staggers and/or varying magnet types (eg alnico 2 under the treble strings, alnico 5 under the bass strings), but not those ones.
For the last question, you're describing star grounding, and it works great regardless of whether the central point is on a pot or external to it like in your suggestion.
As long as you're still grounding all the pot casings and connecting to the ground lug of the output jack, you don't have to use the volume pot casing as the centralized grounding point. However, because the pot casings need to be grounded, you've got to be soldering to them all anyway (unless you have perfect contact between all the pots and a metal pickguard/pickguard shielding).
In fact, the easiest way to star ground a guitar *is* by using the volume pot - it's already there, and is therefore easy to use as a centralized point for all other grounds.
There's nothing theoretically wrong with using an alternate ground point, you just have to be careful to keep everything in either a star arrangement or a "horseshoe" - never a loop. If you connect your new grounding point to a pot, connect that pot to some shielding, and connect that shielding back to the original grounding point, you've created a "one-turn coil" that increases noise instead of decreasing it. Aim for a star configuration (all grounds directly to the same point) and you'll never do that by accident. If that's not practical, the "horseshoe" - where one component connects to the next, but never back to something earlier in the chain - also works.
The artist formerly known as mbene085.
