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Discussion Starter · #1 ·
yeah, i´m crossposting. what of it? thought you guys should be able to shed some knowledge here.

also: i´ll give you guys a nice NGD thread with sexeh pics and clips if you help me out here!

The problem is as stated in the thread title: when i´m not touching anything, and just have the guitar plugged in, i get a loud and terrible "ground fail" buzzing noise. if i touch the strings or the volume pot, the buzz gets lower, but doesn´t disappear. i´ve tried touching things in the electronics cavity, and i´ve tried prodding and poking with a wire to "connect" different parts together, but i´ve been unable to get the ground issue to disappear (other than touching with my bare skin, which obviously has the same effect as touching the volume pot). if i turn the volume pot all the way down, it goes away, so at least the jack is wired correctly and stuff, and it´s not the cable. however, when i turn the volume all the way down, i also get this weird "howling" noise. the whole guitar is also microphonic, and i can record people talking if i want to.

the howling changes between two pitches, and i can affect which pitch it will be in by moving the wires in the cavity and stuff.

these buzzing is present in all 3 pickups positions, although it changes tone in the middle and neck positions. it gets brighter and more audible. it´s also not a problem at all if i change guitars, so it´s obviously in this specific one.

i´m thinking it´s either the bridge not being grounded properly (it´s got single-string bridge saddles, so each saddle is grounded individually), or it´s the volume pot. alternatively the bridge pickup could be whacked, and is somehow affecting the other one and whacking the ground out of balance or something.

i´m GUESSING it´s the volume knob though, since it´s howling and stuff... anyway, does anyone have any tips for me? i´ve gone over the wiring in the cavity, and it´s all legit and properly done and everything, so no problem there. it´s got to be either bridge, pickup, or volume pot.

fake-edit: i´m kinda thinking it´s "probably" the bridge, really. but i don´t know.

here´s a clip of the buzzing (it´s a standard "whoops i forgot to ground LOL" noise, but hey!) and the howling: http://dl.dropbox.com/u/3782113/WTFWIRING.mp3

real-edit: hah, i didn´t know tags are made automatically like that! that´s hilarious! look at them! it´s like they´re describing a crazy night out partying! :lol:
 

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Canis lupis robertus
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Has this been re-wired?

You're likely going to need to post pics so the wiring gurus can see what the halibut is going on.

Sounds like a ground issue 100%, but my guess is the real culprit is a bad pot.
 

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Dream Crusher
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Sounds like Roter's electrical work to me!

Congrats :yesway:
 

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Discussion Starter · #5 ·
yup! :lol:
the funny thing is that i checked the wiring, and it looks like it should be correct.

the guitar sounds amazing acoustically, plays amazing, and is really comfy, plus it looks fantastic, so i can´t bring myself to send it back for something as silly as a wiring issue. sure, shame on them, but i´ve had worse payoffs when buying new guitars. anyway, here are three pics of the electronics cavity, in slightly different angles so you can see where all the cables connect:




as further motivation, have some wenge!
 

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Dream Crusher
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Those switches are shitty. You should get a real leaf-type switch. I dunno if that'll solve your issues, but it should work and feel worlds better.

Also, if all of the bridges are not grounded properly and the nut is not metal (as a metal nut or string retainer bar across metal strings should ground everything) it might be worth running some copper foil under all of the saddles so they're all grounded.
 

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Discussion Starter · #7 ·
graphite nut, so that´s not the problem. i´m going to check the saddles already.

any other suggestions?

oh, and as you can see in pic 1 and 2, the switch is just small enough to fit in the cavity. will a better switch still be small enough do you think?
 

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Dream Crusher
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Well, the graphite nut could be a problem. The advantage to a brass nut with individual bridges is that you only need to ground one bridge to ground each string.

An SG switch might fit. That's the issue with working in such a thin body though.

Try wiring the bridge pickup straight to the jack, then to pot to jack, then to switch to jack. Isolate the problem.
 

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Discussion Starter · #9 ·
there´s a metal string tree, so i think that would help, but guess what?

i think i probably found the problem.

the bare wire going under all of the saddles (one long bare wire onto which all of the saddles are mounted) is covered by what looks to be a satin finish. it´s actually under the clearcoat. on the entire guitar the clearcoat is so thin that you can´t even see or feel it, other than a smoothness to the wood. you can feel the grains, and it feels totally open-grained, but it´s got a little bit of finish on it. the low f# saddle came off, and i saw the wire sticking out. no problem, i thought. then the low B came off, and i saw that it was under the finish, and the logo stamped on the underside of the saddle was imprinted on this finish.

in other words, the saddles weren´t touching the wire. it was separated by the finish.

so tomorrow i´ll be removing all the saddles, and slapping a wire under there to properly ground them all.
 

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AVH Guitar Repair
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Hey Morten...it's definitely a grounding problem, and possibly something else. Those components are rock-bottom cheap, they're right. A real CTS pot and a proper Switchcraft SG toggle (or very slight internal shave route), would work just fine. Sounds like you figured out the bridge wire issue, as I was going to suggest that. If you are going to eventually upgrade those parts, I would also lose the horrible, cheap barrel jack, route the entrance slightly, and install a Neutrik locking jack - you'll never have a jack issue again, as those barrel jack contacts wear out quickly, short, and cannot be retensioned.

Looking at those pics, from the angles you posted, it looks like the black wire's contact is bent over and touching the toggle housing's retaining tab - another possible ground problem would insure from this, causing a short or noise.

This must be the new guitar you contacted me about...I'm just sorry I'm not setup yet, or I could completely fix and upgrade this for you easily. But as I said, I won't be ready to take on work for another month or so. :(
 

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Discussion Starter · #14 ·
well, i don´t have the cash to send it to oslo anyway, so that´s aww-rite :D

i think i´d rather rack up a series of upgrades for a guitar and send it to you, since minor fixes like these aren´t too hard to fix.

i have a gazillion upgrade plans for all my guitars though, so when you get a shop going, tell me! :p

and i´ll check out the other electronics stuff. i have some volume pots laying around ready to be unpacked and used, and i guess i can hunt down a small-ish switch easy enough.
 

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Discussion Starter · #15 ·
alright, so i made a new ground for the bridge saddles. it definitely helped with the bridge, but the problem is still there. the only difference is that now touching the strings and stuff grounds it better than before.

i tried wiring the pickup hot directly to the jack, but that didn´t work. i can´t remember if i grounded the bridge to the jack ground though, but i touched the ground wire, and it fixed it right up.

so i´m seriously out of suggestions. i can retry the direct-to-jack wiring, removing the bridge ground from the volume pot, and wiring it directly to the jack together with the pickup ground.

that way i would remove all contact with the volume pot. the only other suggestion would be a pickup malfunction i guess. unless somehow there´s a problem with the jack. the buzzing goes away if i turn the volume knob down though, so the jack itself doesn´t induce the buzz.

dammit, halp?!
 

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AVH Guitar Repair
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All components must be grounded together, from the output jack inwards, including the bridge ground wire, and in some cases the control cavity shielding.

When isolating potential shorting issues, you need to check each component in the chain, one at a time, until you find where the possible problem is. It helps if you have a meter (pref. digital volt/ohm multimeter) to check for continuity, but if you don't, do it the basic way:

First, get a known, good, noise-free cable, and use as clean, flat, and quiet an amp signal as you can get for testing.

Second, start at the sound source: the pickup(s). Unsolder the pickup leads and connect them directly to the cable plug - hot to tip, and ground to sleeve. I use alligator clip wires, but you can just hold them on with one hand if you have to just for this test. Listen carefully to the signal for undue noise or hum. Seems ok, then strum the strings and listen if it sounds normal in terms of output etc. Bend and jiggle the pickups leads a bit while it's attached to the plug- listen for crackling or shorting. None? Then your pickups are most likely fine, unless it sounds thin with much lower output, which could mean one coil is either shorting out or severed and dead. You can determine which coil is dead by lightly tap testing each coil's polepieces individually with a screwdriver tip.

If the pickup is fine, then solder the pickup and bridge ground wires directly to that cheap-ass barrel jack, which are often a source of shorts because of the lousy, flimsy internal contacts that prematurely lose tension and short (as you can see I'm not a barrel jack fan). Obviously, hot to tip (short lug) and both grounds to the jack ground (threaded sleeve lug). Plug it in and repeat the listening procedure again, and wiggle the plug around while it's plugged in and listen for shorts. Hopefully fine? Then go the next step.

Wire the pickup just to the pot - hot to 1st lug, ground (+ bdg grd) to pot casing, ground wire from pot casing to jack ground, and center lug on pot to jack hot. Repeat listening tests. Turn and wiggle the knob while playing. If ok, then take knob and pull it upwards while turning to check for a cracked wiper plate. If the pot is ok, then the most likely culprit is the toggle. Remove pickup and now you're basically back to where you started, which by this time the problem should have surfaced and/or be pretty apparent by now.

And this is a very simple circuit, just imagine how it is to troubleshoot preamps, or anything else with PC board...:ugh: This is often how it is with tech work that a lot of people forget or wonder why it takes so long sometimes - sure, the actual 'fix' often only takes a couple of minutes with an iron, but it took 30 minutes to find and isolate the issue. It is very frustrating sometimes...

Hope this helps. Good luck Morten :)
 

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Discussion Starter · #18 ·
after trying everything, it´s still not working. Apophis told me to send it back, and they´d fix the problem. at least i don´t have to spend eternity trying to locate and fix the problem, and i don´t have to spend money for someone else to fix it.
 

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Mr. Negative Pants, ,
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Wirelessly posted (Dethphone: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_1 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8B117 Safari/6531.22.7)

I had almost the exact same problem once when one of my George L's cables was messed up. I'm not entirely sure what the exact electrical issue was, but I think it was some kind of weird loop caused when the signal and ground were connected intermittently, or maybe the ground open at the guitar end.
 

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