Buzzing bass advice

mark_jwedge

The bass player in my band had terrible problems with Buzz at a gig this weekend. He plays a fender P bass into an orange amp (sorry I don’t know which one). Pedal board is just a boss tuner and EHX bass muff.

The buzz disappeared when he turned the guitar volume down but didn’t change when touching any metal parts on the guitar or using the ground lift on the amp. So I think it might have been the pickups buzzing perhaps from the lighting or some of the other gear in the venue.

Just thinking of things that might help. Cavity shielding the guitar? Noise suppressor pedal? He does daisy chain the EHX pedal from the boss tuner, would using a dedicated power supply with transformer isolated outputs help?

UnclePsychosis

I'd be tempted to check that the bridge ground wire is still connected (use a multi meter to measure continuity).

If that's fine, then I'd be tempted to investigate shielding. 

Did the sound change if he moved around/rotated the bass? Thats normally a good sign that it's external interference.

Re: the pedals, I wouldn't expect a daisy chain to be a problem with those two, and if turning down the bass volume made it go away its almost certainly not the pedals making the noise. Bear in mind, though, that if you leave a big muff 'on' and stop playing then it will inherently amplify any existing noise - muffs are really quite high gain. 

ICBM

mark_jwedge said:

The bass player in my band had terrible problems with Buzz at a gig this weekend. He plays a fender P bass into an orange amp (sorry I don’t know which one). Pedal board is just a boss tuner and EHX bass muff.

The buzz disappeared when he turned the guitar volume down but didn’t change when touching any metal parts on the guitar or using the ground lift on the amp. So I think it might have been the pickups buzzing perhaps from the lighting or some of the other gear in the venue.

Just thinking of things that might help. Cavity shielding the guitar? Noise suppressor pedal? He does daisy chain the EHX pedal from the boss tuner, would using a dedicated power supply with transformer isolated outputs help?

The bridge ground wire isn't making a good connection, most likely at the bridge end - corrosion can get in under the bridge, quite common. You'll need to take the bridge off to fix it, but luckily that's not difficult on a P-Bass. Strip a bit more of the wire if there isn't enough to make sure only the metal is trapped and not the plastic, or if it isn't clean. I prefer to poke the end of the wire down one of the screw holes when refitting it, which helps guarantee a permanent contact.

Cavity shielding would also help a lot, since the string ground is really using the player's body to compensate for lack of shielding. A noise suppressor pedal is really a band-aid and won't help when he's actually playing, although it will when he's not. It's not the pedal or the power supply, the noise is coming from the bass if turning the volume down stops it.