PJ Pickups humming/buzzing

Does it stop when you touch the strings?
Get worse when you touch the strings?
Any change when you rotate 360 in the room?
Hum remains when P pickup is solo’d?

 

Hi!!

Does the bass hums when you have the P solo? If the J pickup is a standard single coil, it is normal to have some hum when that pickup volume is on.
I have a PJ Jazz Bass that started with a Seymour Duncan Quarter Pound set. I ended up replacing the J pickup (because of the hum) for a Dimarzio Ultra Jazz (which is a split coil J Pickup, with no noise) and never looked back. I have owned this bass for like 10 years:



Cheers!

 

Oh, It might be a problem with other electrical stuff plugged in the place, or worst-case scenario, a problem in the apartment electrical setup, hopefully just in the room or outlet you're using.

I'm having a similar issue, actually... My roomate works in the healthcare system, so due to the pandemic thing I moved to my girlfriend house with all my recording stuff (my girlfriend is VERY happy about this [joking]). And most of the time that I record music in our room I get this annoying buzz...

At first I though it was something in my effects chain, but sometimes without doing anything the buzz just stops. One day I noticed that when unplugging my laptops charger the buzz stopped. But next time, this didn't make any changes.

Maybe you could try different wall-outlets in the room, or if using a multi-outlet, try to avoid overcharging it with many things.

I wish I could help more, but I'm not too technical in this field.

EDIT! I forgot one simple question: Does the amp hums when you turn the volume up, without any instrument plugged in??

Good luck!

 

Sounds like it could be RF interference. I had a p bass that buzzed worse than my j bass; until I shielded it. Getting worse when you change direction is a symptom...

Also could be the grounding of the outlets...

I’d experiment wit all the variables; try as many amps as you have, different outlets/ rooms, turn off computers/ lights (especially fluorescent)

Good luck!

 

I’ve only done a P bass, never a PJ or J... I’d poke around the forum, I’ve seen some very thorough threads on the subject- good luck!

I will say the process was fairly easy, and rather enjoyable!

 

Well that stinks! Hope the tech gets to the bottom of it, and you have a positive outcome

 

isolate the p pickup and it should be quiet

the j pickup is the problem because it is single coil

 

If you shielded the cavity you need to leave a small amount of shielding wrapped above the cavity for the control plate to contact. Also you need to make sure you soldered a ground wire from the back of the pots to the shielding and if you used more than one piece of shielding they need to be solder connected otherwise you just installed a bigger antenna

 

Is there a ground wire coming from the bridge? It doesn't look like it from your pic. That'll cause buzz. If your Bass doesn't have a pre-drilled hole from underneath the bridge to the body cavity, have your Luthier drill one or use a external ground strap like you see on some vintage Jazz Basses.

I do "star" grounding meaning all grounds eventually come to a single point to a small ring terminal screwed into the shielded body cavity. I prefer shield paint over foil tape but both do work.

Good luck!

I also use Fender foam ground plates under each pickups and ground those to the Star point.

 

Make sure you have a ground wire to each cavity and soldered to the shielding and back of a pot.

 

What happens when you disconnect the P pickup?
Disconnect it by removing the wire on the bottom lug of the pot. Do the same with the J pup.

Try wiring each pickup directly to the jack.

 

I hate to mention it, but where is your phone? I played a gig a while back and watched a guy about pull his hair out chasing weird noises from the PA and his amp. Between poorly grounded main wiring and the cell phone sitting on top of his amp, he had a symphony.