P-Bass style wiring

C^8 · Post by **C^8** » Tue Apr 17, 2007 4:01 pm

I'm working on my rewiring/shielding my girlfriend's (cheapo) Ibanez TR bass due to a horrible hum it gets when the tone is cranked up.

If I touch the tone/vol knobs the hum stops, so I'm assuming it's a grounding problem?

I have used BG's shielding guide to make the insides all metal clad and such - now I just need to re-do the wiring (the part I always get confused by).

The bass has 2 single coil offset pups in the P-Bass tradition, so I hunted down a Stewmac wiring diagram and will try and follow it.

Now ... how do I alter the wiring so it dosn't loop with shielding I've done?
Keep in mind I am no electrical engineer

ash · Post by **ash** » Wed Apr 18, 2007 2:00 pm

Don't alter the wiring. Just make sure the sheilding only contacts at the volume pot body.

C^8 · Post by **C^8** » Wed Apr 18, 2007 2:35 pm

Thanks, ash. I'm going to give it a try this weekend.
If it still dosn't fix the hum I'm just going to throw the bass in the trash... It's only an Indonesian plywood job after all

The only thing I'm not sure if I can copy in that stewmac diagram is connecting a ground wire to the bridge (it wasn't done in the original wiring as far I can tell)... but if the cavities are shielded should this matter?

ash · Post by **ash** » Wed Apr 18, 2007 2:50 pm

Earth the bridge. The strings are a sheild when earthed, an aerial when unearthed.

C^8 · Post by **C^8** » Thu Apr 26, 2007 11:27 am

Cheers, ash.
Despite my godawful looking soldering the bass is now humless!
The ground wire from the bridge was removed by whoever had mucked around with it previously - So, I put in a new one and re-wired the pots (new pots + capacitor) and thankfully it worked.

Thanks also to BG for his shielding tips too