Guitar Grounding Common Misconceptions?

Discussion in 'Tonefreaks' started by jonesy, Jul 23, 2010.

  1. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    I have heard a theory where some people bodies act as an antenna and actually add noise into the guitar. But not sure if that is really true or not. I know you act as a ground when you touch the strings.

    Hum or buzz comes from bad soldering, improper grounding or a partial short somewhere in the circuit or pickups.
     
  2. JakeDSL

    JakeDSL Junior Member

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    Working (soldering is extreme;y tedious and difficult work.) Trust me, I've tried learning from this and other forums for years now, and there is a magic and talent to it. You can't just learn how to do this. It takes many many many hours of trial and (mostly) failure as well as hands on guidance from an experienced pro. You cannot just learn to fix a guitar over the Internet. Period. There are many things that must be learned and discussed that only can arrive from a human element involved in your learning process.
     
  3. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Soldering up guitar wiring and other components is not rocket science or "magic" and there is definitely some skill involved. And like anything the more you practice and spend time learning about it the better you get at it.

    I have had dozens of people with minimal experience purchase harnesses and DIY kits from me an successfully installed and assembled their own wiring and pickups. True enough that some people are just not cut out for this type of thing, but many are. Sounds like maybe you have had problems and are speaking more from personal experience, but you shouldn't discourage those that are willing to try.
     
  4. SuiteAmpCo

    SuiteAmpCo Senior Member

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    I just iinstalled a new harness in my SG. I used the RS 50's wiring scheme (very clean and easy to do). I shielded the cavity 100% with copper tape with condujctive adhesive. Since this took a lot of small pieces to cover gaps I ran a braided ground sleave and soldered it to the tape inbetween the pickups and to the back of the neck vol pot. I get ground continuity like a dream anywhere on the guitar (a tuning post to a comparment cover screw). I took the ground wire from the tailpiece and used it to wrap and sorta wire tie my pickup leads (2 wire, inner wire & braided ground). That is how I found it when I opened the electronics compartment, so I gave it the same purpose when I rewired it.
    So far the guitar is DEAD quiet. Even with my crappiest practice equipment its noiseless. Should I solder the tailpiece ground wire to my jack or one of the pots? Or leave it? I did notice a hum before I replaced the wiring when I lifted me hands from the strings. Is this the result of a bad tailpiece ground? Btw its a Gibson Faded Special SG (lil $700 model) with big boy electronics in it now.
     
  5. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    The ground wire to the tail piece studs normally solders to the back of the neck volume pot in SG's. They way that ground works is, when it is connected properly any slight noise will be gone when you touch the strings. So sounds like it was connected and working fine before the re-wire.
     
  6. guitarnut_germany

    guitarnut_germany Senior Member

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    I have buzz and hum, even when the guitar is not plugged in. When I touch the metal part of the plugged in cable jack, not the tip (cable is plugged into the amp but NOT the guitar), OR any metal part on the amp, the buzz is GONE. Does that mean I have dirty AC power??

    I checked the connection from bridge to jack on the guitar with a multimeter and it sems ok. I think the guitar itself is grounded ok.

    This has been really frustrating for me!

    cheers
     
  7. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Hard to say exactly but maybe pickup an outlet tester like this and see if your outlet is properly grounded. The humm could also be from another source like a computer or dimmer switch etc. Or you may have a tube going bad or faulty power transformer in your amp?

    [​IMG]
     
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  8. guitarnut_germany

    guitarnut_germany Senior Member

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    I tried my other amp at home, there was still a slight buzz, but nowhere near the buzz I had with my mesa stiletto in our practice room. It's a really old building there and I suspect the AC power might be bad there.... I'll try the stiletto at home for a comparison!
     
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  9. goldtop56

    goldtop56 Senior Member

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    ok so i am about to start wiring my epiphone 56gt like they did in the 50s im pretty new to wiring guitars so was hoping someone could give me a wiring diagram that is simple to follow i have got 2 PIO caps a .22 and a .15 i have got gibson braided wiring some cloth covered wire i will be using the stock pots switch and jack as i wanted to see what difference the 50s wiring had first, so hopefully someone will be able to help me
     
  10. pmonk

    pmonk Senior Member

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    I have developed a pretty bad buzz on my 1975 Deluxe which was post-factory routed for full HB.

    The original pots where replaced with 500k pots. It was fine when first done, but it was int he closet for a few months then when I plugged her in I get a horrible buzz that goes away when I (1) touch the metal casing of the guitar cord (2) touch the metal screws on the pup rings, or (3) touch any metal with my foot?

    Do I need to re-do the soldering?
     
  11. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Maybe try spraying some contact cleaner into the pots and work them back and forth. You may have some oxidation that developed in them from sitting and that could be causing some problems.

    While you have the cavity cover off also inspect for any switch or pickup wires that may be bent or touching.

    It could also be a bad patch cord, dirty power supply or a faulty tube in your amp.
     
  12. Quill

    Quill Senior Member

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    Here is an excellent post written out by member "spitfire" in The_Sentry's thread about how he fixed his P-90 guitar. It's just a great post, and entirely germane to this important topic.

     
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  13. mangus

    mangus Senior Member

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    I'm starting my harness tomorrow and I have a doubt that I hope you can help me with, can I use U grounding shape with modern wiring or only with 50's wiring? Sorry if question is completely idiot but I've never done this and I want to do the best job possible.
     
  14. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Yeah no problem, you can use the U ground with either modern or 50's wiring and it will work just fine.
     
  15. CRAZYokiSKATER

    CRAZYokiSKATER Senior Member

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    Thank you for this thread. Great help... :D
     
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  16. canon_lespaul

    canon_lespaul Junior Member

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    Hi there,
    I am seeking some feedback / advice.
    I recently completed my first pickup and wiring change after much research on mlp forum.
    I wired my guitar to 50's wiring, and the new pickups are vintage output unpotted PAF's.
    Volume and tone controls for each and combined pickups work just fine.
    However there is a higher level of buzz than before and in comparison to my other guitars when the hardware is untouched, however when touching the hardware the buzz is elimated to a very low level consistent with pre wiring / pickup change.
    This reinforces to me that all is well with my wiring (touching hardware grounds the circuit?), and I put it down to the unpotted pickups, but it's still bugging me that maybe the bridge grounding wire connection could be a cause, but given when touching the ground wire the buzz reduces the buzz as elected, that signifies that the guitars grounding is working well????
    I've read that unpotted will create more micro phonic feedback at high gain, but will they also create more buzz when idle, or have I maybe got a grounding issue?
     
  17. Frogfur

    Frogfur Senior Member

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    Interesting to say the least. Nice information.
     
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  18. Cozmik Cowboy

    Cozmik Cowboy Senior Member

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    None of my guitars have input jacks...........:cool:
     
  19. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Hmm then maybe they have output jacks :cool:
     
  20. FourT6and2

    FourT6and2 Senior Member

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    Already brought up pages and pages ago. But in a guitar that uses braided 2 conductor leads, all of the pickup and switch braids are touching each other in the wire channel before they reach the control cavity. You can start on the back of the neck volume pot, for example, and follow ground from the pot casing to the neck pickup braid up to the switch or bridge pickup braids then back down to the bridge volume pot casing. Then around the ground wire to the bridge tone pot casing, to the neck tone pot casing, and back to the neck volume pot casing. Is this not a ground loop? And if so, then there are multiple ground loops in a guitar's wiring. The pickup braids, switch braids, and jack braid are all touching. And even if all the braided leads were isolated with shrink tube, the switch and jack braids are all connected by a wire wrapped and soldered around all three up by the switch. So there's another loop that you can follow back around multiple times from multiple points. Basically, every ground connection in a typical Gibson using 2 conductor braided leads is connected to every other ground connection multiple times. How is this not a ground loop?
     

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