Grounding Issue, Epiphone SG

Discussion in 'Epiphone SG' started by Uncle Curse, Apr 7, 2019.

  1. Uncle Curse

    Uncle Curse New Member

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    Greetings my fellow Guitar nerds!


    I'm having some grounding trouble with a Epiphone SG.

    It's been standing by it self in a corner for quite some time according to my friend that owns it, and after going trough my own know how, i have to admit defeat, so far.
    Now, what i have done is the following

    1. Changed the Jack Socket from the guitars native Epiphone socket to a replacement, and replacement seems to give a little less noise, go figure?
    2. Removed old wire ends, on the parts i've worked on, and giving the new ends a bit of solder before reattaching them to their respective points
    3. Detached the grounding wire at the end that isn't connected to a potmeter, for more free movement of the for mentioned wire end, in the hope of figuring out where it could be placed for maximum noise reduction
    4. Tried to have the loose grounding end touching both parts of the saddle, (i might get the correct English terms for specific parts wrong), and where else the wire could reach other metal parts in the guitar, still to no avail
    5. A lot of head scratching and coffee sipping
    In the hopes of finding a solution to the this current predicament with your help
    Thanks in advanced
    Uncle Curse
     
  2. donepearce

    donepearce Well-Known Member

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    We need to know the symptoms. Is it a hum that disappears when you touch the strings?
     
  3. Bad Penguin

    Bad Penguin Active Member

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    Or is a hum that develops WHEN you touch the strings?
     
  4. Layne Matz

    Layne Matz Well-Known Member

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    I reccomend using unsheilded metal wire wrapped around everything and going to ground. Its foolproof in my experiences. Look up PRS Ground wireing.
     
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  5. Uncle Curse

    Uncle Curse New Member

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    Sorry for the lack of information :)
    The humming gets more intense if i touch any metal part,
    got to admit i don't know exactly that indicates, other than bad grounding.

    Right know the grounding wires one end is soldered onto the top of the bridge pick up pot, and the other end, is the loose one i can reach the saddle with, and yet, still buzzing with no contact of hands, and it intensifies when i do touch any metal part of the guitar.


    Thanks for the tip! I'll look up some wiring diagrams and see what i can figure out.
    Any recommendations of a diagram for an Epiphone SG?
    Still pretty green on guitar wiring, specifically :p
     
  6. donepearce

    donepearce Well-Known Member

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    It sounds like the grounding wire is not contacting the bridge (or stop bar). If you have a multimeter, test on ohms between a pot body and the strings. They should be connected.
     
  7. DrBGood

    DrBGood Well-Known Member

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    Do you have a black wire in the cavity, that is coming out of a little hole pointing to the bridge ? If not, there is your problem. That should be grounding one of the bridge post from below.

    Stop bar: end part of the bridge system where strings are first threaded.
    Bridge: part with saddles between stop bar and bridge pickup.
    The ensemble is called a TOM, short for Tune-O-Matic.
     
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  8. Col Mustard

    Col Mustard Well-Known Member

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    Welcome to ETSG!

    Here is a link to a StewMac page where they sell all the parts you
    need to replace your entire wiring harness.

    https://www.stewmac.com/Pickups_and_Electronics/Wiring_Kits/Premium_Wiring_Kit_for_Gibson_SG.html

    You might not have to
    replace everything, but the cool part about StewMac is:

    They show you how to do it.

    And that ought to help you. There is a video on that page that should
    be helpful. They also have easy to read wiring diagrams, click on them
    and they appear. Like this:

    https://www.stewmac.com/How-To/Onli...d_Wiring/Switchcraft_3-way_Toggle_Switch.html

    The ground wire ought to be attached to your guitar's bridge, through a
    hole drilled in the wood. It's called the 'string ground" and if it's connected anywhere on the bridge or stop bar post, you'll be grounded.
    That ground wire should then be attached to
    the ground pole on your output jack... the one you replaced.

    I have the ground wire connecting all the tops of the pots and the ground
    pole of the toggle switch to the same point on the output jack as well.
    So all of the parts are grounded, as is the bridge.

    Then your guitar should be silent.

    In my experience, the electronics are one of the weak points of an Epiphone guitar. Many of us have simply replaced the whole harness, so we could move on and play music. Upgraded electronic parts are a good
    improvement to an Epi, highly recommended.

    But many others here will say, "if it is not broken, don't fix it..."
    And I don't argue with that.
     
  9. Bad Penguin

    Bad Penguin Active Member

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    Very simple, your ground is not connected.
     
  10. Layne Matz

    Layne Matz Well-Known Member

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    I reccomend taking out the old ground wires and using the PRS method beciade its dead simple and seemingly fool proof. A thread of broken wire or joint can lead to excess buzzing. I was having a world of grounding troubles on every guitar I worked on until i stopped using regular wires for grounding and switched to the PRS method. You dont even have to solder with this method if you really dont want to, I do so nothing gets knocked out of place. The PRS method runs a thick gauge wire (one solid wire withno threads or sheilding) from the output to the tone pot, to the volume pot, to the switch and then to the bridge. Do thr same with an Epiphone except remove the old ground wires because they are more prone to issues and if you have 2 tones and 2 volumes(4 pots total, then after wrapping the wire around the bridge pots wrap the around around the neck pots, then to the switch and then finally put the end of that wire in the bridge post hole where the current ground wire is located.
     
  11. Layne Matz

    Layne Matz Well-Known Member

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    The ground wire in my Epi G400 and EB0 Bass was in flush with the bridge post, in the string ground but not soldered to the post. I mention this becuase I've seen many people say it should be soldered to the post but thats not the case on either of these Epiphones.
     
  12. donepearce

    donepearce Well-Known Member

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    No, you don't solder to the bridge post. The wire should be a crush fit between the threaded insert and the body.
     
  13. dub-setter

    dub-setter Active Member

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    yap,
    thats what i thought as well....

    check your bridge post/ studs if there any loose cable
    or connection to it..

    see @DrBGood s post.
     
  14. Layne Matz

    Layne Matz Well-Known Member

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    Thanks for clarifying, you read my mind. I wonder where I read it was supposed to be that way but im sure it was more than once.
     
  15. Uncle Curse

    Uncle Curse New Member

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    Holy crap, you guys are awesome!
    Thanks for the tips, tricks and help, really appreciate it!
    Should be able to get it working with all this written knowledge for me to peruse!
     
  16. plankton

    plankton Well-Known Member

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    I don't how you would even be able to solder it to the post.
     
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  17. DrBGood

    DrBGood Well-Known Member

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    Peruse away !
     
  18. Col Mustard

    Col Mustard Well-Known Member

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    yep, that's what this forum is best for.
     

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