Jaguar series pickup wiring

[timtam]

Well I’m not sure if it’s possible to revive such an old post, but as it directly related to my query I thought I’d give it a go.

I’ve recently picked up a MIJ 66 reissue Jag that came with this mod already wired in. However the pickups weren’t great so I bought some Pure Vintage 65s that I’ve wired in instead.

All seems to work but when I put both pickups in parallel (both pickups in the traditional on position) there is a noticeable drop of volume. I know series is meant to be louder anyway, but both on in parallel seems quieter than when I even have individual pickups on.

I’ve not cut the little wire on the bridge pickup as the overall view seems to be that this isn’t necessary for this mod to work, but wonder if I need to try that? I have wired the ground wire of the neck pickup to the shield plate of the 3 selector switches.

Hopefully someone can help!

Thanks.

All modern implementations in recent years of series wiring on jags (ie Marr, Am Pro I) have the shared-ground jumper to the claw cut, and a permanent ground wire added just for the claw (3 wires in total). The avoids making the claw 'hot' when in series mode. Both those guitars use a 4-way switch (2P4T) for series (ie diverting one pickup's coil ground to attach to the other's coil hot). I have a jag with PV65s and the same 4-way wiring .... and there is not a big difference in volume between series and parallel.

But your main problem ATM is with parallel. It's possible you're out of phase when in parallel. Did you buy the PV65's new as a packaged pair ? And used black as ground for both ? (white is hot on one, yellow is hot on the other). If you are indeed out of phase, and have not cut the jumper on the pickup with flipped hot/ground, you will have a 'hot' claw.

[poortomsacold]

Thanks for your reply timtam

Yes, I bought the pickups new as a packaged pair, and have used the black cables of both as grounds and the yellow/white cables as hot.

I do think it sounds out of phase as in addition to parallel being a little quiet, it’s also a pretty think sound. What I can’t work out is how I have managed to put them out of phase! Do you think I need to try and cut the little claw wire and then add another ground to the bridge pickup (on the claw itself)?

[timtam]

Thanks for your reply timtam

Yes, I bought the pickups new as a packaged pair, and have used the black cables of both as grounds and the yellow/white cables as hot.

I do think it sounds out of phase as in addition to parallel being a little quiet, it’s also a pretty think sound. What I can’t work out is how I have managed to put them out of phase! Do you think I need to try and cut the little claw wire and then add another ground to the bridge pickup (on the claw itself)?

Yes, I would cut the jumper and add the claw-only ground wire. It's the "right" way to do series, and might be playing into your problems somehow.


Your pickup wiring sounds correct and so should be in phase. You can check with the screwdriver test on both isolated pickups. You want both pickups deflecting positive or both negative. Best done with an analog ammeter, but can also be done with a multimeter (which of course is easier to find):
In resistance mode ...
https://www.youtube.com/watch?v=2lFQzmRvePc
In DC voltage mode ...
Analog multimeter ...
https://youtu.be/7UfxQBhqen8?t=248
Digital multimeter ...
https://youtu.be/7UfxQBhqen8?t=1120

Analog ammeter, ideally +/- 50uA, centre zero (no power required):
https://www.ebay.com/itm/192800826295
https://www.premierguitar.com/diy/mod-g ... ase-tester

If your problems remain, we'd need to analyse the modded wiring you've inherited.

[poortomsacold]

Thanks for your reply timtam

Yes, I bought the pickups new as a packaged pair, and have used the black cables of both as grounds and the yellow/white cables as hot.

I do think it sounds out of phase as in addition to parallel being a little quiet, it’s also a pretty think sound. What I can’t work out is how I have managed to put them out of phase! Do you think I need to try and cut the little claw wire and then add another ground to the bridge pickup (on the claw itself)?

Yes, I would cut the jumper and add the claw-only ground wire. It's the "right" way to do series, and might be playing into your problems somehow.


Your pickup wiring sounds correct and so should be in phase. You can check with the screwdriver test on both isolated pickups. You want both pickups deflecting positive or both negative. Best done with an analog ammeter, but can also be done with a multimeter (which of course is easier to find):
In resistance mode ...
https://www.youtube.com/watch?v=2lFQzmRvePc
In DC voltage mode ...
Analog multimeter ...
https://youtu.be/7UfxQBhqen8?t=248
Digital multimeter ...
https://youtu.be/7UfxQBhqen8?t=1120

Analog ammeter, ideally +/- 50uA, centre zero (no power required):
https://www.ebay.com/itm/192800826295
https://www.premierguitar.com/diy/mod-g ... ase-tester

If your problems remain, we'd need to analyse the modded wiring you've inherited.

Thanks for that. Can the test also be done with a compass, to save me unsoldering and removing both pickups? I checked the other day and one pickup is north, the other south, if that makes sense? But I did that test with the guitar wired up, not with the pickups out of it.

[timtam]

Thanks for that. Can the test also be done with a compass, to save me unsoldering and removing both pickups? I checked the other day and one pickup is north, the other south, if that makes sense? But I did that test with the guitar wired up, not with the pickups out of it.

Unfortunately no. The compass only tells you magnetic polarity of the pole piece magnets (and will be the same wired or unwired). OTOH the 'screwdriver'/phase test is telling you the ultimate electrical polarity of each pickup's output - which is what you need to match for the two pickups to be "in phase".

The fact that your two pickups have opposite magnetic polarities (one north up, the other south-up) just means that Fender provides the PV65s a RWRP, noise-cancelling pair. Which also requires the above-mentioned red-black and yellow-black designations of hot-ground, to give you opposite coil winding directions. The end result of opposite magnetic polarity/opposite wind direction should be noise-cancelling, in-phase.

[poortomsacold]

Thanks for that. Can the test also be done with a compass, to save me unsoldering and removing both pickups? I checked the other day and one pickup is north, the other south, if that makes sense? But I did that test with the guitar wired up, not with the pickups out of it.

Unfortunately no. The compass only tells you magnetic polarity of the pole piece magnets (and will be the same wired or unwired). OTOH the 'screwdriver'/phase test is telling you the ultimate electrical polarity of each pickup's output - which is what you need to match for the two pickups to be "in phase".

The fact that your two pickups have opposite magnetic polarities (one north up, the other south-up) just means that Fender provides the PV65s a RWRP, noise-cancelling pair. Which also requires the above-mentioned red-black and yellow-black designations of hot-ground, to give you opposite coil winding directions. The end result of opposite magnetic polarity/opposite wind direction should be noise-cancelling, in-phase.

Okay so I managed to find a way of testing with the pickups still in place and that would seem to suggest that the bridge sees a brief increase when I rest a metal rule on the pickup, and the neck a brief decrease when doing the same. I imagine I’ll have to repeat the test again with the pickups out in case this is down to the way it’s already wired.

[poortomsacold]

I have just unsoldered both pickups. On my digital multimeter the readings drop very briefly on both pickups when putting a metal rule on them, so I think this means they are both responding as they should.

With that in mind I wonder whether cutting the bridge claw wire and adding a new ground to the claw will resolve the issue…

[poortomsacold]

Final update (I hope!).

Have resoldered both pickups and also a collection of earths. That seems to have done the trick. No massive drop of volume when putting both pickups on in parallel. Slight boost in series which seems right. Sounds good, no longer thin, so I think this might have done the trick. I think it must have been a dodgy ground somewhere.

I didn’t cut the claw wire on the bridge, so remain unsure if that’s necessary as there seems to be mixed views on that.

Think I’ll rewire it all soon though as the MIJ wires are so thin they’re awful to work with.

Thanks again for all of your help timtam, really appreciate it.