I can hear the tone know being turned

[Skyline]

Hey all,

I recently built a P-bass and wired it up tonight. When i plugged it in, there was some feedback and then when i turned my tone knob, I could hear a loud scratching sound. When i put my finger on the bridge and turn the tone knob however, the sound does not exist.

I have tried swappping polarities and no prevail. Please help ASAP as I have to hand it in for a school project in 2 days

 

[LCMBassist]

Might be an earthing issue? Just a guess, I'm no bass builder!

 

[craig.p]

Make sure you have electrical continuity amongst:

bridge
jack body (threads & nut)
pot bodies
cavity shield
pickguard shield
strings
jack body (threads & nut) on the amp side (cable plugged in of course)

Might help to post a close-up pic of the internals.

 

[primedynasty]

definitely sounds like a grounding issue. are you grounding to the back of the pots? i would take some readings and check that everything is properly grounded. if not that, it could be a bad pot.

 

[Skyline]

Problem solved. Sprayed some contact cleaner on the pot and all is good now

Thanks for the help anyway