Electric shock through bass...

Discussion in 'Basses [BG]' started by mat gregory, Jul 22, 2009.

  1. Hi all, I recently got a shock off the strings on my american deluxe jazz bass. I was playing and was fine, then a sudden sharp shock and then was fine then for the rest of the rehearsal.

    The amp I used was my LMII which is brand new, therefore nothing should be wrong with it, tried other basses and its been fine, tried the amp and jazz bass at home and it was fine.

    Only thing I can think of is that it's dodgy wiring at the church building, as the casing on my previous amp went live a couple of weeks ago so I changed to the Markbass. I used my socket tester which said the power was fine and there was no earth fault.
  2. Maybe open up the outlet (if you are qualified) and see if the earth wire is loose. It's definitely a bad ground connection somewhere.
  3. bassplayeroreo


    Jun 8, 2009
    Tel Aviv
    I had a similar thing happen. I was playing and all of a sudden i started getting shocked from the strings. I later found out it was the cable. I don't know what exactly happens when it starts shocking you, but I don't think you can fix it. Try borrowing somebody else's cable and seeing if you get shocked at all.
  4. BassBob185


    Oct 25, 2007
    Rocking Chair
    Some would pay money to have that 'effect' on their bass all the time.
  5. Thanks for the replys

    dmusic - I'll look into having that mod done.

    I've searched the forum about these issues and the most common answer is "check the ground on your bass"

    If the ground on the bass was disconnected then I wouldnt getting the shock in the first place. Therefore - bass is grounded.

    Since the amp is new and socket seemed okay I am stumped by what caused this shock. It was only an isolated incident, maybe could be static.

    I'll try changing my lead to see if that helps too.
  6. BassBob185


    Oct 25, 2007
    Rocking Chair
    +1 on the static
  7. adhus


    Mar 22, 2009
    Desert Jungle
    The exact same thing happened to me, same bass, same amp same problem.
    What i did was, changed the amp AC cable with the 3 prong (3 legged) plug. I use an LCD computer monitor AC cable, which has a 3 prong plug and a fuse in the plug. But you have to make sure that you check the voltage as well.
    And that's it..good luck
  8. Yeah, we have 3 pronged plugs on all out mains appliances here in the UK as standard as our mains voltage is generally higher - 240V
  9. ByF


    May 19, 2009
    It doesn't seem likely that static would build up on your body if you're touching a bass which is connected to ground--you only get static build-up if you are isolated from ground. Your body is a very good conductor.

    In the world of electronics (and high-reliability devices for space applications, etc.) we put a resistor (1 Megohm) in series with the human body to bleed off static, but prevent electrocution by limiting the current. The capacitor sounds like the same idea, but of course it would pass high frequencies and block 60 Hz, so it would not function very well as a ground to reduce hum in your sound.

    I still go with the original poster's idea that it is something with the wiring in the building. Is there any chance you were plugged into a different outlet than you usually use when this happened? Were you using an extension cord? Maybe that outlet is wired incorrectly? It used to be very common in the US that outlets would be wired in reverse--that was the reason that old amps had ground reverse switches.

  10. experimental bassist

    experimental bassist

    Mar 15, 2009
    I would not rule out an issue w/ the bass. A bad solder joint or similar could be an intermittent open to ground. If the bass has a bad ground, you can indeed still get shocked as the current will use your fingers and body as ground, not good.

    Not likely to be static, as already mentioned a properly grounded bass will dissapate any static charge to ground.

    Do you have an ohm meter? If so, check resistance between your bridge and the "sleeve" portion of your output jack. You should have zero.

    Another test, first *unplug* your amp from the wall, but hook your bass up with the instrument cord. Then measure ohms between your bridge and the receptaple ground prong. Again, you should have zero.

    If your equipment checks out, and it is indeed dodgy wiring in the building, at the minimum you should consider a wireless setup if you wish to continue playing there.

    Good luck, and be safe! :bassist:
  11. Hookus


    Oct 2, 2005
    Austin, TX
    This is one reason I typically don't connect the ground wire to to the bridge unless it is necessary.

    Disconnect the ground wire from under the bridge, and if it still sounds okay, you will never get shocked from the strings. I don't worry about getting shocked from my amp, I worry about the mic and my amp not being on the same circuit!:eek: