Announcement

Collapse
No announcement yet.

Wiring question - guitar makes lots of noise when I'm not playing.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Wiring question - guitar makes lots of noise when I'm not playing.

    Hey. You know how all guitars make a little hum when you're not playing and not touching something grounded (bridge, strings, tuners, etc)? Well one of my guitars hums at least 5 times as loud as the rest. As soon as I touch the bridge, the hum goes away - so it IS grounded properly. The control cavity is shielded with that black paint stuff. And the pickups are DiMarzio humbuckers - so I doubt the pickups are the cause. Any ideas?
    Last edited by Deadlock; 08-15-2009, 09:22 AM.

  • #2
    Have you tried using a different guitar cable? Does your amp have a polarity switch? Have you tried just a different outlet?

    joe...
    www.godwentpunk.com
    www.myspace.com/godwentpunk

    Comment


    • #3
      Yes, I've used this guitar with different amps, cables and outlets.

      Comment


      • #4
        Originally posted by Deadlock View Post
        As soon as I touch the bridge, the hum goes away - so it IS grounded properly.
        It could be that it isn't grounded properly if the hum goes away when you touch the bridge. I'd check all the wiring for an unexpected short too.
        GTWGITS! - RacerX

        Comment


        • #5
          Originally posted by Hellbat View Post
          It could be that it isn't grounded properly if the hum goes away when you touch the bridge. I'd check all the wiring for an unexpected short too.
          I don't think it's a grounding problem. All guitars are more quiet when you touch a grounded part of the guitar. I checked the wiring, I can't figure it out. But I guess it's no big deal, since touching the strings/bridge makes it go away - so when I'm playing it's fine.

          Comment


          • #6
            It's supposed to be as quiet when you're not touching anything as it is when you are touching it.

            If it's not, you're either picking up RF signals (amp, rack, computer, appliances, TV, ceiling fan, cel phone, etc) or there's an internal ground issue.

            Shielding paint is only good if something's actually touching it. If you've got a screw driven into the wood and all grounds meet at that screw, but the actual paint itself is not touching the screw, then all you have is an anchor point for some black wires.
            I want to depart this world the same way I arrived; screaming and covered in someone else's blood

            The most human thing we can do is comfort the afflicted and afflict the comfortable.

            My Blog: http://newcenstein.com

            Comment


            • #7
              Originally posted by Deadlock View Post
              All guitars are more quiet when you touch a grounded part of the guitar.
              nope.
              Originally posted by Newc View Post
              It's supposed to be as quiet when you're not touching anything as it is when you are touching it.
              +1

              The only guitars of mine that hum are ones with single coils - and that's whether your hands are on the guitar or not. If you're getting a hum that goes away when you touch metal, you have a grounding issue. The hum is because the wiring isn't properly grounded and it goes away when you touch the bridge, strings, or whatever because YOU become the ground when you touch it
              Hail yesterday

              Comment


              • #8
                I think the grounding and shielding in many Jackson guitars may be less than satisfactory. I kind of wonder how effective that graphite paint really is. Besides, there is no conductive metal in the back covers, which means the Faraday cage around the electronics is incomplete. A proper back cover should be shielded.

                I've seen a guy who shielded the back cover plate of his KV, claiming that 70% of the noise problems it had went away. I have these kind of issues in varying degrees with my Charvels, so one of these days I'll be bringing out some copper shielding tape and really go to town on them.

                Comment


                • #9
                  I feel like I'm going crazy. I've owned 30 guitars and they all hummed very quietly until you touch a grounded part of the guitar. You guys are telling me this isn't normal?

                  Comment


                  • #10
                    Originally posted by Deadlock View Post
                    I feel like I'm going crazy. I've owned 30 guitars and they all hummed very quietly until you touch a grounded part of the guitar. You guys are telling me this isn't normal?
                    That is my experience as well.
                    You are the ground plane, and that grounding potential gets much larger when you're
                    in contact with it.
                    A perfect ground would be to have one where the ground wire never goes to the bridge.
                    I have tried it with only limited success.

                    Comment


                    • #11
                      Perhaps the shielding paint is forming part of the circuit. I'd check the resistance between the pots and switches. If it's near zero, you are fine. If it's measurable, you might be going across that paint (not good). Perhaps a ground wire came loose. Look for that, or instead drop in a brass grounding plate. I like to use brass grounding plates (to form the circuit) in combination with shielding paint (to shield EMI away from the circuit).
                      _________________________________________________
                      "Artists should be free to spend their days mastering their craft so that working people can toil away in a more beautiful world."
                      - Ken M

                      Comment


                      • #12
                        I've experience twice with Jacksons that whoever did the wiring had mixed up the terminals of the pots. In both cases, this caused a lot of noise.
                        Last edited by javert; 08-20-2009, 12:46 PM.

                        Comment


                        • #13
                          Only time I had this issue was with my first guitar, a Hondo H76 strat-ish guitar. Everything since has had better electronics (pickups at least) and no issue of noise. Well, except the real strat, but that doesn't go away when you touch it..
                          Every man dies... Not every man really lives!!

                          Comment


                          • #14
                            Originally posted by VitaminG View Post
                            nope.

                            +1

                            The only guitars of mine that hum are ones with single coils - and that's whether your hands are on the guitar or not. If you're getting a hum that goes away when you touch metal, you have a grounding issue. The hum is because the wiring isn't properly grounded and it goes away when you touch the bridge, strings, or whatever because YOU become the ground when you touch it
                            Hit the nail right on the head. You have a grounding issue..

                            Comment

                            Working...
                            X