Buzz problem with tone pot

lenosgood · #1 02-01-2011, 03:39 AM

I have an Affinity P-bass that has a buzz when I turn up the tone pot. It goes away with the treble backed all the way off, and is unaffected by touching the strings. At first i thought it might be a ground problem in the house wiring, but I unplugged the bass and the amp is silent. Is it just a bad tone pot or what?

allexcosta · #2 02-01-2011, 04:59 AM

Is the cavity shielded?

WayneS · #3 02-01-2011, 05:03 AM

Quote:

Originally Posted by allexcosta

Is the cavity shielded?

+1

Its still going to be a noise issue. The noise has to have a source, and that source wont be a pot.

Vincent P · #4 02-01-2011, 05:10 AM

Is this something which has developed recently, or was the noise always present?

lenosgood · #5 02-01-2011, 05:28 AM

Quote:

Originally Posted by allexcosta

Is the cavity shielded?

I doubt it. It's just an Affinity.

Quote:

Originally Posted by Vincent P

Is this something which has developed recently, or was the noise always present?

I'm not sure. I used to use a crappy little practice amp that was noisy itself, and I just got a Fender Rumble 60 which is a huge improvement. The only time I hear the buzz is when I turn the tone pot up. When it's all the way down, no buzz. When it's up, there's a steady buzz and little pops when I touch the strings. I'm thinking it's either a ground problem or a pot problem, but I'm not sure. I just want to get an idea before I open the thing up. I'm going to plug the amp into another plug to rule out any grounding issues there, but I'm almost positive it's something in the bass.

allexcosta · #6 02-01-2011, 05:44 AM

Quote:

Originally Posted by lenosgood

I doubt it. It's just an Affinity.

You could've done it. Since you haven't, here we go:

http://www.stewmac.com/shop/Electron...pper_Tape.html

lenosgood · #7 02-01-2011, 08:17 AM

Sorry, I meant it's just a stock Affinity. I haven't done anything to it besides getting it properly set up.

randall p · #8 02-01-2011, 08:20 AM

Unaffected by touching the strings? Check the ground to bridge.

lenosgood · #9 02-01-2011, 08:26 AM

all I get from touching the strings is a tiny pop sound. Otherwise, nothing.

lenosgood · #10 02-01-2011, 09:18 AM

Okay, I removed the bridge, positioned the ground wire so it was making better contact, and it helped a little, but still buzzing. I pulled the pickguard, checked the solder connections, they all look good. I tried this, though. I turned on the amp without a cord plugged in. Quiet. I plugged in the cord without the bass, got a buzz through the amp. Could it be the cord that's bad or is that normal? It may be a stupid question, but i don't know for sure so what do you think?

Bassamatic · #11 02-01-2011, 09:28 AM

The pot is not causing the buzz, it is just rolling it off when you turn it down, so you hear it less.

Does it do this at any other location? I have a spot in my room near my computer that has a lot of buzz on my jazz basses - computers are very noisy that way and generate a lot of electrical noise.

While your pickups are hum canceling, it seems that there is some hum pickup in your wiring. Check to see that all is grounded properly, and if all else fails do the copper shielding around the controls and ground it to the output jack.

lenosgood · #12 02-01-2011, 10:31 AM

Okay, went and got another cord...I wanted one with an "L" jack on it anyway, and after everything else I've done, the buzz is only present when I'm not touching the strings. With the tone turned all the way to the treble side, it's quiet as long as I'm touching the strings. Is there a better way to attach the bridge ground? When I removed it earlier, I stripped a little more insulation off the wire and curled it around one of the screws. I thought that this would give me a better ground, but I guess not. All the solder connections look good and none of them feel loose. Any tricks to getting a better ground or just plan on shielding the cavity?

Vincent P · #13 02-03-2011, 05:16 AM

Strip the wire to expose a bit more and see if this improves. Double check the wiring from the manufactures site and verify that the ground to the tone pot is good using a meter and checking for continuity.

lenosgood · #14 02-03-2011, 05:26 AM

I already stripped the bridge wire back about an inch and placed it in another spot and looped it around one of the mounting screws. I haven't checked the connections with a meter yet, but all the connections seem sound. I'm going to wait to open it up again until I get the shielding tape so I can do it all in one shot. When checking with a multimeter, the connections should show zero ohms, right?

RambleOn · #15 02-03-2011, 12:03 PM

I had the exact same problem.
In my case, the problem was the ground cable, on the input jack, was connected loosly. Took me forever to find it, re-soldered it properly and the noise was gone. Might not be the same thing but check it just in case.