Page 1 of 4 1 2 3 ... LastLast
Results 1 to 10 of 32

Thread: Return of: Guitar Wiring Issues

  1. #1
    Join Date
    Feb 2013
    Location
    Boston, MA
    Posts
    111
    Thanks
    8
    Thanked 2 Times in 2 Posts
    Rep Power
    20132

    Return of: Guitar Wiring Issues

    Sign in to disable this ad
    A few years ago I decided to use my cheapest guitar for experiments. I had always wanted to change pickups, tuning heads, etc. I also went a step further and put in all new pots, knobs and toggle switch. I did something wrong. I was getting some really awful noise out of it. I didn't know how to fix it, gave up and put it aside for almost a year. I then took it to one of my coworkers who's good with electronics. His best guess was that I burned out one of my pots. I was bummed that I had done that but glad I had something to go on. I bought four new pots and even a new toggle switch. I put everything together again (with all new wiring as well). I'm still getting an awful amount of noise. The noise goes away whenever I touch anything that's grounded, and it gets amplified when I grab any of the signal wires [the signal wires for the pickups (orange) or the output wire from toggle switch to input jack (blue/cyan)]. Here's what I've got:

    guitarwiring-jpg

    I'm left-handed. Also, one of my mods was to remove the old 1/4-inch pots and replace with 3/8. That's why it's a bit cramped in there. It's driving me nuts! I miss playing this thing!

  2. #2
    Join Date
    Aug 2017
    Location
    Texas USA
    Posts
    2,089
    Thanks
    177
    Thanked 392 Times in 356 Posts
    Rep Power
    2298480
    You have a multimeter? I'd start with simply confirming you've got the tailpiece grounded and all pot cases grounded to that and that's what's connected to the shield connector of the 1/4" output jack.

    Set all pots on "10" and then check that resistance needs is ZERO for all things that should be connected to ground; and everything else you touch somewhere between 5-15k depending on pickups. This is easier if your multimeter has one lead with an alligator clip, but just keep one on the ground at output and start poking around. Look for something that's not reading zero that should be.

    That's some pretty gnarly looking wiring there. I'd probably rip it out and start over, but maybe it's salvageable if you can tell us what's connected and what's not.
    "... I know in the mornin' that it's gonna be good
    when I stick out my elbows and they don't bump wood." - Bill Kirchen

  3. #3
    Join Date
    Jan 2015
    Location
    paradise
    Posts
    4,340
    Thanks
    102
    Thanked 552 Times in 497 Posts
    Rep Power
    8012023
    For starters, yeah the wiring is a mess.
    But also, I don't see any of the lugs on the volume pots grounded.
    Looks like a les paul style cavity, but volumes are on top and tones are on bottom. Traditionally both volume pots are closest to the neck and tones closest to the back.
    Google a les paul electronics cavity pic and copy that.
    Your soldering itself doesn't look half bad, no big globs or anything. But the layout is sloppy. Can't tell what's going where.
    Also, braided wiring will go a lot towards making it more quiet.
    I'd disconnect everything and start from scratch.

  4. #4
    Join Date
    Feb 2013
    Location
    Boston, MA
    Posts
    111
    Thanks
    8
    Thanked 2 Times in 2 Posts
    Rep Power
    20132
    I hope this is clearer. I tried to draw out how I have things wired up.

    wiring-handdrawn-jpg

  5. #5
    Join Date
    Jan 2015
    Location
    paradise
    Posts
    4,340
    Thanks
    102
    Thanked 552 Times in 497 Posts
    Rep Power
    8012023
    Ok so being left handed would at least explain why your volume grounds are wired up in reverse.
    Ok, back to noise. We have NO idea what exactly you consider noise. The perceived noise may just be normal.....or not. I'm not there to hear it and see whats going on.

    First, on ANY guitar with passive pickups there is going to be a string ground. When you touch any metal part of the guitar including the strings, it will reduce noise. And of course if you touch any hotwire, it will make a noise. (But you generally don't go touching the hot when you're playing. Lol )
    Thats normal.
    However..... All your wires are single conductor without shielding. (adds noise)
    Assuming everything is wired up correctly shielding on the wires and shielding the cavity itself will reduce noise.
    How about your jack. That wired correctly?

    Edit : I still say start over. Used braided wire. Also your switch has no ground. Needs to be grounded too.
    Last edited by RFR; 02-19-2019 at 19:12.

  6. #6
    Join Date
    Feb 2013
    Location
    Boston, MA
    Posts
    111
    Thanks
    8
    Thanked 2 Times in 2 Posts
    Rep Power
    20132
    ...Also your switch has no ground. Needs to be grounded too.
    It doesn't? That's what the green wire coming off the top of the toggle switch and going to the neck-volume pot is supposed to be. Did I get that wrong?

  7. #7
    Join Date
    Jan 2015
    Location
    paradise
    Posts
    4,340
    Thanks
    102
    Thanked 552 Times in 497 Posts
    Rep Power
    8012023
    Bottom line. Rewire it.
    Last edited by RFR; 03-09-2019 at 21:48.

  8. The Following User Says Thank You to RFR For This Useful Post:


  9. #8
    Join Date
    Aug 2017
    Location
    Texas USA
    Posts
    2,089
    Thanks
    177
    Thanked 392 Times in 356 Posts
    Rep Power
    2298480
    I'm assuming the wire from the back of the switch to the pot case (purple in my attached markup) is the switch ground.

    Still, any attempt to check this without confirming continuity and appropriate resistance (impedance proxy) is a guessing game. NOBODY should be doing wiring on an electric guitar without a multimeter. You can get one that will confirm continuity and resistance close enough for guitar work for under $10. The one I have (after my dear, 50 year old RCA bit the dust) was like $4 at Harbor Freight.

    wiringhd-jpg
    "... I know in the mornin' that it's gonna be good
    when I stick out my elbows and they don't bump wood." - Bill Kirchen

  10. #9
    Join Date
    Feb 2013
    Location
    Boston, MA
    Posts
    111
    Thanks
    8
    Thanked 2 Times in 2 Posts
    Rep Power
    20132
    Ok, so I got a digital multimeter and checked the pots. It does read zero for everything that needs to be grounded. For my volume pots, I get about 3.4 k-Ohm open (i.e. pot at "10") and about 1.7 k-Ohm "closed" (i.e. pot at "0").

    As for added noise, I plugged my guitar directly into my audio interface: my RME Fireface UCX. With no cable plugged into Mic/Line 2, it reads about -100 dB (with no added gain). With an instrument cable plugged in, it reads the same. With a known good guitar (my BC Rich Mockingbird), it reads almost the same -98/-97. With my WIP guitar, it reads about -85, so with my wiring the way it is, I'm getting about a 15 dB increase in noise.

  11. #10
    Join Date
    Aug 2017
    Location
    Texas USA
    Posts
    2,089
    Thanks
    177
    Thanked 392 Times in 356 Posts
    Rep Power
    2298480
    Those DC resistance measures seem low to not right. Not sure what pickups you have but a single pickup shouldn't measure that low.

    Here's a video that's Ok to show a LP where the individual pickups are measured. (You only have to watch from where it starts to the "Loose" title start.) You'll notice in the video that when both pickups are selected the resistance is about 1/2 - technically (r1+r2)/2 - so if you have the switch in the middle maybe that 3.4kΩ value makes a little sense.



    P.S. If those numbers persist on single pickup switch settings, you need to pull all that wiring and measure the pickups to see what they read individually, then carefully wire just the volumes and switch and confirm that's working correctly, then add in the tone pots one at a time, rechecking the wiring. Individual pickups should go to zero when volume is dialed all the way back.

    The obvious question not asked yet is what are the pot values you're using? 500kΩ is typical for humbuckers, with an audio taper (IMO).

    P.P.S. I'll say again I think it should be redone and cleaned up. I was looking closely at it and it seems like you've got you're volume pots wired together in some way, though it's damn hard to see what's going on in that rats' nest. See the orange wire that looks like it's attached to both where I've put the yellow arrows.
    guitarwiring2-jpg
    Last edited by keith.rogers; 03-09-2019 at 20:15.
    "... I know in the mornin' that it's gonna be good
    when I stick out my elbows and they don't bump wood." - Bill Kirchen

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Headset Wiring Issues!
    By ranjam in forum Microphones
    Replies: 3
    Last Post: 04-29-2009, 09:41
  2. Telecaster Wiring Issues (lots of detail)
    By bobandshawn in forum Guitars and Basses
    Replies: 18
    Last Post: 07-02-2008, 05:10
  3. guitar wiring
    By brendandwyer in forum Guitars and Basses
    Replies: 7
    Last Post: 07-14-2007, 06:54
  4. STC issues surrounding holes in drywall for wiring
    By darwin in forum Studio Building & Acoustic Treatment
    Replies: 3
    Last Post: 03-09-2003, 04:43
  5. Guitar wiring
    By Cooperman in forum Guitars and Basses
    Replies: 3
    Last Post: 11-14-2000, 18:55

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •