JB Pickup problem!

[grxmx]

I've got what I'm assuming is an older model JB pickup. It has a paper sticker that just says "JB J" on it instead of the barcode sticker & all that. Anyhoo, it sounds better than any JB I've ever heard.

I play Marshall Superleads pretty loud, and I stand pretty far away, so feedback has never really been a big issue. But lately the JB has developed this uncontrollable LOOOUD DEEEEEP hum that only goes away if I firmly press my fingers on the setscrews that hold the pickup in the saddle. Its like a "WHOOOOOMMMPH!" sound. Its never done this before, and the stock pickup from my guitar does not do this. Ive checked the wiring, its all secure, firm and good to go. I backed the pickup up almost 1/4" off the strings and it STILL does it.

Its driving me nuts, because I cant solo up high because that low feedback overrides it. There's a few points in the room where it doesnt do it as bad, but it still does almost everywhere.

Please help!

 

[jeremy]

Re: JB Pickup problem!

soudns like you might have a microphonic pup, a little wax bath should do the trick

 

[RG 2570]

Re: JB Pickup problem!

I've got what I'm assuming is an older model JB pickup. It has a paper sticker that just says "JB J" on it instead of the barcode sticker & all that. Anyhoo, it sounds better than any JB I've ever heard.

I play Marshall Superleads pretty loud, and I stand pretty far away, so feedback has never really been a big issue. But lately the JB has developed this uncontrollable LOOOUD DEEEEEP hum that only goes away if I firmly press my fingers on the setscrews that hold the pickup in the saddle. Its like a "WHOOOOOMMMPH!" sound. Its never done this before, and the stock pickup from my guitar does not do this. Ive checked the wiring, its all secure, firm and good to go. I backed the pickup up almost 1/4" off the strings and it STILL does it.

Its driving me nuts, because I cant solo up high because that low feedback overrides it. There's a few points in the room where it doesnt do it as bad, but it still does almost everywhere.

Please help!

that is definitely a grounding problem, do you have the bare wire and the green wire of the JB to the top of the pot?
both have to be connected for a proper ground

 

[grxmx]

Re: JB Pickup problem!

Well, its not a grounding issue, the pickup has been in the same guitar for 3 years, and I checked them all and all appear good. I'll give the waxing and see what happens.

 

[Lewguitar]

Re: JB Pickup problem!

Loud deep hum is a grounding issue...not a microphonic issue. Microphonic pickups squeel with a high pitched ringing and hurt your ears. They don't hum loud and deep. Something has happened to disturb the grounding of your pickup. I'd remove it and inspect every connection...especially the bare and green wires as RG 2570 mentioned. And I'd try to check them out inside the pickup too, if I could. If pressing on it really hard eliminates the hum, your pressing is causing the ground connection to be completed again in the immediate area of the pickup itself...and it would also seem to be in the pickup or pickup wire close to the pickup and not in the solder joints or control cavity of your guitar.

 

[grxmx]

Re: JB Pickup problem!

Ok, I removed the pole pieces and took up that coil and the bare wire is grounded fine, and everything appears intact. I reassembled it and now........it doesnt do it......at all :/