PJ both pickups humming 50hz, touching strings quietens it

[R-B-Y]

Hello,
I did some searches and found that this is likely a shielding issue. I have checked all of my groundings and they are all securely soldered on.
The problem is that the p pickup, supposedly humbucking, still hums when singled out, and not at all quieter than the j pickup. Additionally touching the magnets on the half closer to the string makes it worse, when the other magnets do nothing. Not sure if this is normal or not.
The bass in question is a mij fender aerodyne jazz bass

here’s the wiring

 

[andare]

If the noise goes away when you touch the strings then your bass is not shielded or not shielded properly.
Is there a ground wire screwed into the body?
Is the bridge grounded? Check with a multimeter.
Even after shielding, touching pole pieces might make noise.

 

[Killing Floor]

Do the following test:

1) is it a Fender?

If the answer to step 1 is affirmative the bass isn’t shielded and most likely not properly grounded. See avatar, I play Fenders. But when Leo Fender was still at Fender shielding was not considered a big deal because electric instruments were in their infancy. Therefore, Fender never changed it because it was good enough for Leo in the 50s and hasn’t discouraged people from buying.

When I buy a Fender (I have several Ps and Js and Teles and a Strat) I make a list of parts I need to have on hand before it is playable in a studio or public application. Always shielding cooper tape or shielding paint. I usually use the tape so I can connect and include the pick guard. It’s easy. And Fender won’t do it.

 

[andare]

Do the following test:

1) is it a Fender?

If the answer to step 1 is affirmative the bass isn’t shielded and most likely not properly grounded. See avatar, I play Fenders. But when Leo Fender was still at Fender shielding was not considered a big deal because electric instruments were in their infancy. Therefore, Fender never changed it because it was good enough for Leo in the 50s and hasn’t discouraged people from buying.

When I buy a Fender (I have several Ps and Js and Teles and a Strat) I make a list of parts I need to have on hand before it is playable in a studio or public application. Always shielding cooper tape or shielding paint. I usually use the tape so I can connect and include the pick guard. It’s easy. And Fender won’t do it.

Fender Players are shielded from the factory, though they sometimes do a half-assed job. Very easy to verify too. There should be a ground wire going from the back of the volume pot to a washer and a screw into the cavity, which is painted with black shielding paint.

True to 50s and 60s Fenders, Fender Vinteras are not shielded. Neither are their predecessors the Classic Series 50s, 60s and 70s (not 100% sure about the 70s).

MIA Fenders are probably all shielded but the cavity will have been painted like the body over the shielding paint. Again, the presence of a ground wire screwed into the cavity is a dead giveaway.

I know nothing of CIJ and MIJ Fenders.

Current production Squiers are made in Indonesia and shielded from the factory like the Players, usually much better.

 

[Killing Floor]

Fender Players are shielded from the factory, though they sometimes do a half-assed job. Very easy to verify too. There should be a ground wire going from the back of the volume pot to a washer and a screw into the cavity, which is painted with black shielding paint.

True to 50s and 60s Fenders, Fender Vinteras are not shielded. Neither are their predecessors the Classic Series 50s, 60s and 70s (not 100% sure about the 70s).

MIA Fenders are probably all shielded but the cavity will have been painted like the body over the shielding paint. Again, the presence of a ground wire screwed into the cavity is a dead giveaway.

I know nothing of CIJ and MIJ Fenders.

Current production Squiers are made in Indonesia and shielded from the factory like the Players, usually much better.

Sounds like you have a lot of good experience with Fender shielding your basses. Here is mine currently:
2021 Mod Shop P from Corona - no factory shielding paint or tape.
2020 Mod Shop Telecaster HH from Corona no shield paint or tape, no bridge wire installed.
2019 MiA Stratocaster HHS no shielding paint or tape, no bridge ground.
2019 MiA Pro Jazz no shielding paint or tape, bridge ground wire was installed at the factory.
2015 P Bass MiA no shielding paint or tape.
2021 MiM Telecaster no shielding paint or tape.
1977 MiA Jazz no shielding paint or tape.
1973 MiA fretless P no shielding paint or tape.
1973 MiA modified J fretless no shielding paint or tape.
1986 MiA P Bass no shielding paint or tape from factory.
1999 Jazz MiA no factory shielding paint or tape.

I am currently lusting after a 1966 P locally. I’ve seen the cavity. No shielding.

I could go on. I’ve been playing Fenders since the late 70s and I’ve owned several dozen and I have never bought one that was properly shielded. But I am not suggesting yours were not. Just that of the over 30 I’ve owned, made between 1973 and 2021, none came to me with shielding paint or copper.
I love Fender and I will always own and play their basses and guitars. But as I said earlier, there’s work to be done before they get gigged or recorded.

 

[andare]

Sounds like you have a lot of good experience with Fender shielding your basses. Here is mine currently:
2021 Mod Shop P from Corona - no factory shielding paint or tape.
2020 Mod Shop Telecaster HH from Corona no shield paint or tape, no bridge wire installed.
2019 MiA Stratocaster HHS no shielding paint or tape, no bridge ground.
2019 MiA Pro Jazz no shielding paint or tape, bridge ground wire was installed at the factory.
2015 P Bass MiA no shielding paint or tape.
2021 MiM Telecaster no shielding paint or tape.
1977 MiA Jazz no shielding paint or tape.
1973 MiA fretless P no shielding paint or tape.
1973 MiA modified J fretless no shielding paint or tape.
1986 MiA P Bass no shielding paint or tape from factory.
1999 Jazz MiA no factory shielding paint or tape.

I am currently lusting after a 1966 P locally. I’ve seen the cavity. No shielding.

I could go on. I’ve been playing Fenders since the late 70s and I’ve owned several dozen and I have never bought one that was properly shielded. But I am not suggesting yours were not. Just that of the over 30 I’ve owned, made between 1973 and 2021, none came to me with shielding paint or copper.
I love Fender and I will always own and play their basses and guitars. But as I said earlier, there’s work to be done before they get gigged or recorded.

I hope I didn't come off as trying to school you because I wasn't. Who am I to do that! I won't suggest you're lying either Fenders all need work before they're playable, totally agree with you.

My Player Precision came with half-assed shielding, the cavity was merely splattered with black paint, the ground wire was installed but the bass buzzed. I had to shield it with copper tape. I also had to fix fret sprout, file and polish the fret ends and angle the neck because the bridge is slightly misaligned.
I had a Vintera P for a weekend, I returned it because there were too many issues. No shielding but tons of fret sprout.
I had a Classic Series Tele and still have a Classic Series Strat - no shielding but tones of fret sprout. I see a pattern there.
I've never had MIA Fenders but the ones I played didn't buzz so I assumed they were shielded. I saw as much on this forum but a ton of issues on those as well.

I don't know when they introduced shielding but it must be recently and inconsistently. For some reason my Squier basses are shielded. Go figure.

I'd say we have slightly different experiences of these instruments we love but we are both a testament to Fender's shoddy QC

 

[micguy]

Well made P pickups nowadays have a copper strip with adhesive (the adhesive is conductive) on the back of the pickup. That copper strip is connected (by a wire) to the ground in your bass, and that grounds the pole pieces - hum gone. I'd be willing to bet your bass doesn't have this. It's easy to install (if you know what you're doing with a soldering iron).

While shielding the cavities also helps, grounding the pole pieces is actually more important. I'd start there.

 

[Killing Floor]

I hope I didn't come off as trying to school you because I wasn't. Who am I to do that! I won't suggest you're lying either Fenders all need work before they're playable, totally agree with you.

My Player Precision came with half-assed shielding, the cavity was merely splattered with black paint, the ground wire was installed but the bass buzzed. I had to shield it with copper tape. I also had to fix fret sprout, file and polish the fret ends and angle the neck because the bridge is slightly misaligned.
I had a Vintera P for a weekend, I returned it because there were too many issues. No shielding but tons of fret sprout.
I had a Classic Series Tele and still have a Classic Series Strat - no shielding but tones of fret sprout. I see a pattern there.
I've never had MIA Fenders but the ones I played didn't buzz so I assumed they were shielded. I saw as much on this forum but a ton of issues on those as well.

I don't know when they introduced shielding but it must be recently and inconsistently. For some reason my Squier basses are shielded. Go figure.

I'd say we have slightly different experiences of these instruments we love but we are both a testament to Fender's shoddy QC

I love Fenders, so I don't want to come of as disliking the brand. And with only a couple exceptions even the non-Fender instruments I have are pretty clearly influenced by Fender. As I'm sitting here I'm taking a mental break from trying to learn Wichita Lineman on my Fender baritone Tele. Yes, wishful thinking, that is a difficult song to do correctly. It's all good, we're having fun talking about basses. This is a happy space. Rock on!