Humming Pickup Noise

PabloClark · #1 05-12-2011, 05:28 PM

Hello TB, I am hoping you can help me figure out why my bass is making a humming noise all the time. I've got an Epiphone Thunderbird with the all the standard settings, the humbucking pickups and all. It has three knobs, one for each pickup and one for the tone. Whenever the tone one is turned up a pretty loud humming noise comes out the amp, the sound turns louder as the knob is turned on. I've tried with different amps and it doesn't make a difference. I opened the wiring compartment and everything looks in order. If anyone has any ideas what the problem is and how can I fix it I would be really grateful. Thanks!

LIONFURY · #2 05-12-2011, 06:06 PM

wow we have the exact same issue.

Bobster · #3 05-12-2011, 06:34 PM

Does touching the strings make any difference to the hum, and have you shielded the electronics compartment?

Bob

NoiseNinja · #4 05-12-2011, 06:41 PM

A shielding should get rid of the noise. As bob says if the humming apears only if you are not touthing the strings.

PabloClark · #5 05-12-2011, 06:50 PM

No, I haven't shielded the compartment and I know there are some threads around here that tell you how to do it, so I will get on it.

But the noise is still there if I touch the strings or play a note, it just sounds a little bit fainter when I do.

greghol · #6 05-15-2011, 10:53 PM

Hello all! My first post!

I picked up my TB Pro IV (pre amp version) last Friday and it is doing the same thing. Especially when the treble is turned up. Touching the strings will make it worse but touching the ground shield on the plug will make it go away. From what I read on a TB Pro thread here on Talk Bass it is a ground problem. One person touched up the connections and it went away and I think another person said the pickup wasn't grounded or not very good.

I haven't opened up mine yet. But I'm contemplating to take it back to the store for the tech to look at since it is new bass or to just do it myself and save the hassle.

Greg

SGD Lutherie · #7 05-16-2011, 11:17 AM

I've been having a lot of people tell me the T-Bird pickup hum. They aren't supposed to. I think Gibson has a quality control issue.

greghol · #8 05-17-2011, 02:50 AM

Quality issues for sure. I looked at my July 2010 built bass and the battery wire connector pin was backing out of the preamp interface connector! Also, the battery connection clip for the 9V battery had a cold solder joint. Couldn't get it to solder back on. Will have to pick up a 9V battery clip tomorrow.

There is a link in this thread that points to another thread on the Gibson forums. Good info on reducing hum w/ schematics. I connected the red wires from the pups to the + (red) side of the battery and it reduced the hum to almost nothing. I didn't do any other mods like relocated the pup grounds. I did add a wire from the vol pot case (gnd) to make connection to the foil back plate for grins.

Active/Passive pickups? Epiphone T-Bird Pro's

Greg

SGD Lutherie · #9 05-17-2011, 10:59 AM

Quote:

Originally Posted by greghol

There is a link in this thread that points to another thread on the Gibson forums. Good info on reducing hum w/ schematics. I connected the red wires from the pups to the + (red) side of the battery and it reduced the hum to almost nothing. I didn't do any other mods like relocated the pup grounds. I did add a wire from the vol pot case (gnd) to make connection to the foil back plate for grins.

Active/Passive pickups? Epiphone T-Bird Pro's

Greg

It wouldn't make sense for Gibson to use active pickups and not power them up... nor should they be working that way.

Those schematics don't show a power connection to the pickups either.

But who knows with Gibson?