grounding issue

Discussion in 'Luthier's Corner' started by chachainsaw, May 18, 2005.


  1. chachainsaw

    chachainsaw

    May 18, 2005
    i just got this P Bass as payment for building a website, it needs some work. it didnt have a jack when i got it, i put one in last night and it works, but theres a pretty loud hum whenever i touch the bridge. i havent put strings on it yet, but i can only imagine that it will hum when i touch the strings too.

    the ground wire is mounted under the bridge and is making a good connection, should i try grounding it somewhere else?

    any help would be much appreciated.. thanks.
     
  2. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    I don't mean to make you sound like you don't know what you're doing, but did you connect the other end of the ground wire to the jack? If you need P-Bass wiring plans, Fender has them, and they're free. A bit difficult to read at first, but quite free.

    Other than that, I really can't think of any reason why there should be a hum.
     
  3. chachainsaw

    chachainsaw

    May 18, 2005
    the ground wire is connected to the tone pot.
     
  4. I dont really know to much about this but when I had a little hum I re sheilded my control cavity and that helped
     
  5. chachainsaw

    chachainsaw

    May 18, 2005
    actually it was connected to the volume pot. but i just tried wiring it to the jack and it works now.

    and i really dont know what im doing, so no offense taken.
     
  6. ArtisFallen

    ArtisFallen

    Jul 21, 2004
    you're getting a hum when you touch the bridge? or are you getting a hum when you stop touching the bridge?

    if you're getting a hum when you stop touching the bridge, it's normal, but if it's bad, shield your cavity.

    if you're getting a hum when you touch you bridge, then it's probably wired wrong, and needs to be re-done.

    here's the schematic if you happen to need it
    http://www.stewmac.com/freeinfo/I-0139.html
     
  7. chachainsaw

    chachainsaw

    May 18, 2005
    yeah, i was getting a hum when i touched the bridge. i re-wired the ground to the jack. its all good now. thanks anyways.
     
  8. jamiedunce

    jamiedunce

    Jan 21, 2005
    Ive got a similar problem. On my spector Pro q-4, Im getting a hum when I touch the pickups, but its grounded properly. Its quite a loud hum too and pretty annoying. Any ideas?
     
  9. If you touch a pickup pole pieces you'll get a hum, this is normal, because you're basically grounding the hot when you do that.
     
  10. jamiedunce

    jamiedunce

    Jan 21, 2005
    They are EMG-HZ passive humbuckers though. Ok, so I took the bridge off and made sure it was grounded properly. Then put it back on, and now it hums when I touch the strings and the pickups!