Polarity of neck and bridge Jag pickup

[Guitarman555]

Need help with polariry..
I have installed a jag 63 staggered black bottom pickup into my 64 jag(to replace incorrect reissue pickups before), searching for the second real vintage pickup to buy and place into the bridge position.
Is polariry really necessary to know? If polariry of bridge will be same as of my neck pick up, is it really a problem...? hum will be bigger or just the same as in single position? I understand that there will be no cancellation hum effect but it shoud be still fine?
thanks!

[timtam]

You need to distinguish between magnetic polarity and electrical polarity. If the pickups do not have the same electrical polarity (both positive or both negative), they will be "out of phase". Unfortunately no pickup maker publishes their electrical polarity AFAIK (but they may tell you if you ask). But it's readily tested with the "screwdriver test" (once you have the pickup !). A pickup's electrical polarity results from its particular combination of magnetic polarity and coil wire direction.

You can check magnetic polarity with a magnet brought close to the top of the pickup (opposites attract).

If a pair of pickups have opposite magnetic polarities (one south-up and the other north-up), they can be hum-cancelling (when combined in the middle position) ... if the coil wires are wired in opposite directions in the guitar. Then they will also have the same electrical polarity (so "in phase"). If you have to flip the hot and ground wires on one jag pickup to achieve opposite coil wire directions, it will likely also involve having to cut the little jumper to the claw and adding a separate ground wire to the claw (only a few jag pickups already have that).

On the other hand if both pickups have the same magnetic polarity (both north-up or both south-up), as you imply you can't get hum-cancelling/in-phase (unless you were to use a strong magnet to flip the magnetic polarity on one pickup). But depending on where the second pickup comes from, it could still be out of phase with what you have (in which case you would need to do the wire flip/separate claw ground as above).

[electric__ralph]

Is polariry really necessary to know?
thanks!

Polarity is not necessary to know, and it won’t be a problem. I just installed some Fender 52 Tele pickups, which aren’t hum canceling, and they work fine. Hum isn’t any different than it is for any other single coil pickup.

[timtam]

Is polariry really necessary to know?
thanks!

Polarity is not necessary to know, and it won’t be a problem. I just installed some Fender 52 Tele pickups, which aren’t hum canceling, and they work fine. Hum isn’t any different than it is for any other single coil pickup.

If a pickup set came from the same source, then of course the pair will be in phase (same electrical polarity). But with pickups from different sources/eras, you have to be lucky for them to be in phase. So magnetic polarity (and/or RWRP) is not the only issue.