Microphonic pickup - what can I do?

Supernautilus

New member
I believe the Jazz pickup in the neck of my single cut guitar is microphonic. I just realized this today. I was noticing a weird tone from the guitar over the last couple weeks. I couldn't figure it out at first. Then I narrowed it down to the neck pup. Makes a loud noise when I tap it. MUCH louder than the bridge pup. And I can hear my voice ever so slightly if I talk loudly into it. And it just has a really bad hollow sound that I know is not right. It just sounds bad.

I have had this pup for almost 15 years at this point. I have no doubt that all my monkeying around with it has caused this in some way. I've had it apart several times recently to change magnets and I feel like that's when it started going bad. I opened it up again to check it and everything seems tight.

From what I've read online, wax potting is the solution. But I don't have any experience with that. Is that my only option? Are there any other solutions for this that I can try at home? Any advice or suggestions would be greatly appreciated. Thank you.
 
i think you should gift it to me :D

having it potted would most likely fix the issue. you could do it at home, but if you dont have bees wax, paraffin, a thermometer, and a way to double boil... its easier to have someone else to it. unless you plan to do more in the future
 
So I can just double boil a mason jar in a pot of water? I have those I think. The only stuff I think I would need to buy is the wax and a thermometer. Any ideas on where I can I get that stuff cheap?
 
Does it have a cover? You could just put double-sided tape over the slug coil and press the cover onto it.

If it doesn't have a cover, and you've been changing magnets, you could just take a blow dryer (not too hot) to warm the wax potting that is there and squeeze it gently but firmly to put it back together in your hand, just hold it until it cools down. (Don't squeeze the coil wires, just press the bobbins to the plate.) Then perhaps retighten the coil screws once more.
 
Does it have a cover? You could just put double-sided tape over the slug coil and press the cover onto it.

If it doesn't have a cover, and you've been changing magnets, you could just take a blow dryer (not too hot) to warm the wax potting that is there and squeeze it gently but firmly to put it back together in your hand, just hold it until it cools down. (Don't squeeze the coil wires, just press the bobbins to the plate.) Then perhaps retighten the coil screws once more.

No it doesn't have a cover so that's not an option.

Forgive me, I'm a little unclear on your next suggestion. Are you saying to raise the coil screws first? How far up? And then heat the pup and squeeze the bobbins against the baseplate until it cools? Then lower the coil screws again? Do I have that right?
 
I kinda like non-potted pickups. They translate dynamics really well. I could see it being a problem for people using a lot of gain and volume, though.
 
I kinda like non-potted pickups. They translate dynamics really well. I could see it being a problem for people using a lot of gain and volume, though.

Yeah I have a Seth Lover which is non-potted and it sounds fine. But there is definitely wrong with this pup. It sounds bad. It's picking up every vibration that hits it. If I hit it with my pick, it sounds like someone tapping on a glass ashtray lol.
 
Yeah I have a Seth Lover which is non-potted and it sounds fine. But there is definitely wrong with this pup. It sounds bad. It's picking up every vibration that hits it. If I hit it with my pick, it sounds like someone tapping on a glass ashtray lol.

If it was for me, I'd start by checking if the screws holding the coils are lot loose... If the magnet or mag poles vibrate on the baseplate, it can be very annoying.

If wax potting is a problem with a not covered PU's, there's 'ghetto tech" solutions. A lenght of soft adhesive tape under and over the mag can help (as well as under the slugs, BTW). Plumber tape (the white one) around the screw poles can be useful too and shouldn't be seen if properly put.

I know it sounds totally amateurish but I've used these reversible tricks to tame microphonic transducers without ruining them with wax potting (which is not reversible and risks to increase the stray capacitance, making the pickup less open and alive, if not a bit dead harmonically if overdone).

Now do what you want and be happy. :-)
 
If it was for me, I'd start by checking if the screws holding the coils are lot loose... If the magnet or mag poles vibrate on the baseplate, it can be very annoying.

If wax potting is a problem with a not covered PU's, there's 'ghetto tech" solutions. A lenght of soft adhesive tape under and over the mag can help (as well as under the slugs, BTW). Plumber tape (the white one) around the screw poles can be useful too and shouldn't be seen if properly put.

I know it sounds totally amateurish but I've used these reversible tricks to tame microphonic transducers without ruining them with wax potting (which is not reversible and risks to increase the stray capacitance, making the pickup less open and alive, if not a bit dead harmonically if overdone).

Now do what you want and be happy. :-)

Thanks for the tips! I have already checked the bobbin screws and they seem tight. I'm guessing the vibrations are coming from somewhere else. I'll try the hair dryer thing first and if that doesn't work I'll try putting some plumbers tape in there and see it that quiets things down.
 
You can find canning wax at hardware stores, home stores, and grocery stores. You can also find candy thermometers at grocery stores. I used to use a thermometer but don't anymore. In my experience the point where the wax melts and becomes semi-cloudy is in the right temperature range.
 
wax potting (which is not reversible and risks to increase the stray capacitance, making the pickup less open and alive, if not a bit dead harmonically if overdone).

Wax potting increases capacitance???? I had no idea! I thought it was more or less electrically invisible to the pickup.
 
Wax potting increases capacitance???? I had no idea! I thought it was more or less electrically invisible to the pickup.

Yes... There's a topic about that here: https://guitarnuts2.proboards.com/thread/8739/wax-potting-experiment-capacitance-microphonics

It's not that I'm friend with the guy who did these tests but his thread and my own data tell the same thing about this capacitive effect of wax. It's variable and doesn't necessarily harm the tone but it's there, simply because any material has a dielectric constant.

That said, not sure that my geeky rambling is useful in this case, since the Jazz pickup evoked above was normally wax-potted initially, AFAIK... :-P
 
I would think this pup was potted when it was made, it's kinda SOP for new pickups unless specifically stated otherwise if I'm not mistaken. Definitely try the blow dryer thing first.
 
Oh wait, do you mean the bobbin screws? The 4 screws on the bottom of the baseplate? Is what you're saying to tighten aftewards?

Yes the 4 bobbin screws. Don't loosen them first. Just warm the pickup up (you can even do it in your hand by holding it for a while), and when the pickup is warm, squeeze the bobbins down toward the baseplate, which should press the bobbins and magnets/spacers altogether with the base plate. Then just check the 4 bobbins screws on the bottom/baseplate and make sure they are tight after pressing everything together.
 
UPDATE:

So I took the pup out again to take a close look at it and I noticed something weird. It looked slightly lopsided. One side was higher than the other by about 1/32 of an inch, when measured on opposite sides relative to the base plate. Being a curious guy, I unwrapped it and took the bobbin screws out so I could get a good look inside. I saw what looked like a black plastic spacer on the slug side opposite a metal spacer under the screw side. The black spacer seemed thicker than the metal spacer and this is what appeared to be causing the slight height difference. I'm not sure if this is normal or if it could cause any issues. I just wanted to point this out because it seemed odd.

Anyways, I saw no way of easily addressing this so I put the pup back together and heated it up with a hair dryer. I gently placed it into a clamp which softly squeezed the bobbins to the baseplate. I waited for the pup to cool and checked the bobbin screws again. One in particular seemed looser than I remember. I think unscrewing it a bunch of times may have made it somewhat loose. Again, not seeing an instant solution to this, I screwed them all as tightly as I could and then rewrapped the coils with tape.

Also, in the process of reinstalling the pickup, I noticed the mounting screw holes seemed a bit loose. Probably from wear. I ended up replacing the springs with rubber tubing, in the hopes this would cut down vibrations.

So far it all of this seems to have worked fairly well. The worst of the "hollow sound" I heard before is gone. The pup does sound better. On a side note, the UOA5 mag I put in this Jazz sounds pretty damn good. Anyways, if anyone has any further comments about anything I've described here, feel free. :)
 
did you try flipping the spacer 90 degrees? its usually a rectangle so its possible the bobbin is sitting on the tall side, when it should be the short
 
did you try flipping the spacer 90 degrees? its usually a rectangle so its possible the bobbin is sitting on the tall side, when it should be the short

It was oriented correctly. The rectangle shape was very definite so it was easy to see. Thanks for the advice though.

On a side note, I think I’m going to try a different pickup in this guitar. I never thought the Jazz was a very good match for the JB, despite its popularity. Currently looking at a Pearly Gates. I’m seen several mentions of the JB/PG combo here on the forums and I think I’d like that much better. I’d like to try it.
 
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