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#1
ok so i just finished wiring my guitar. everything works. im happy.

however, i was told that the ground wire should be soldered to the bridge peice. i did. however when plugging in the guitar i still get a sligh hum...almost like a 60 cycle hum but its got humbuckers.

BUT, when i touch the bridge or any other metal peice, the guitar gets quieter. what does this mean? should the wire NOT be soldered to the bridge? its pretty much completely quiet when touch the bridge. its still playable now, but it could get better and i dont know how.

thanks.
#2
it's working the way it's supposed to

even with humbuckers, you'll get a little but of hum
the reason the hum goes away when you touch metal, is because you become grounded when you touch the grounded bridge. because of that, you help shield the guitar from radio interference/whatever.

you can try sheilding your cavities if you still think it can get better
#3
well its more noisy than a guitar should be. i mean there is a hum. definitely more so than my otehr guitar (that i didnt build). it can still be played. obviously the louder the amp is the louder the hum is. im just sayin if you touch the bridge, the hum goes away.

perhaps its my bushleague bedroom, first timer wiring job that is just causing hum from lack of quality.

what if i unsoldered the wire from the bridge? i mean keep the wire there, but just chillin, not soldered to anything? does the ground need to be soldered to the bridge?
#4
if you desoldered that wire, then you'd have that buzz whether you touch the strings or not.

having that wire soldere4d to the bridge is what makes the buzz go away when you touch it. not what causes the buzz when you're not touching it


my guess is that the noise is being picked up somewhere in your wiring..
you could try re-soldering the joints if you think you didn't do the best job the first time

or like I mentioned, shielding your cavities might do the trick
what guitar is it/ what pickups are you using?
#5
it is a mid seventies univox hi-flier (mosrite copy). the pickups came with the guitar. they are twangy and very hot.

its got to be something in the wiring. when i touch the front pickup, the buzz goes away...just like touching the bridge. HOWEVER, the rear pickup makes no difference. that one is good.

and like i said before, when i touch the metal peices of the tone/volume knobs the guitar gets quieter.

BUT, the output jack is fine. so rear humbucker and jack are fine, rest of parts are affected. however i do know a ground is working somewhat, because in other configureations the noise was like 5x louder. like i said, it sounds like a 60 cycle hum.
#7
no i didnt shield. is that nessesary? i mean how many factory guitars are sheilded?

it is a 2 humbucker, 1 tone, 1 volume and obviously an output jack.

there is a tremolo bridge which is disfunctional, and a hardtail wraparound is in use. so basically the metal trem assembly is still there to cover up a hole in the guitar and the wire is soldered to the bottom of it.

http://www.google.com/imglanding?q=univox%20hi%20flier&imgurl=http://www.guitarsandeffects.com/guitarimages2006/univox_hi_flier_sb/univox_hi_flier_002.jpg&imgrefurl=http://www.harmonycentral.com/thread/1495078&usg=__fR7wTOL6fdrJDF1z0b8gHUDH3JE=&h=562&w=750&sz=194&hl=en&um=1&itbs=1&tbnid=gVWpfh5gyg39RM:&tbnh=106&tbnw=141&prev=/images%3Fq%3Dunivox%2Bhi%2Bflier%26um%3D1%26hl%3Den%26safe%3Doff%26sa%3DN%26tbs%3Disch:1&um=1&safe=off&sa=N&tbs=isch:1&start=0#tbnid=gVWpfh5gyg39RM&start=0

this is it...just minus the trem arm, and plus a wrap around bridge.
#9
get away from flourescent lights, CRTs, etc. also it could be your house wiring.

you'll get hum even with humbuckers. in order for them to cancel the hum, each coil must have exactly the same number of turns of wire. this is rarely the case.
#10
by other configureations i mean this is my first time wiring a guitar and i wired it 10 different tmes trying to cut down on noise and get all the volume/tone pots to actually work.

this configureation seems to do all the best yet.

my solder joints? all are stong i know that. however why do they need to be round? i mean i suppose i could clean them up and make them round. i didnt think that was nessesary. i just trimmed the excess and made sure all joints were secure.

there are no flourecent lights in my house, and my other guitar plays 100% silent. its me and this guitar. its about 30 years old, and i redid the wiring from scratch (cause the old wiring was literally falling apart and noting worked cause the guy who owne this before me had no brain).

whatever it is it has some effect with grounding, starting at the first pickup. i will probably open it up and try again. however i am reluctant because about about 3 nights i am sick of this.
#11
when you touch the case of the neck pickup, you're touching another ground point and the guitar is still working as it should

the same should happen when you touch the bridge pickup, but i'm guessing the pickup cover has broken away from the base plate.

some pickups are just louder than others..that might just be what it is, man
#12
He did say they were very hot. And maybe shielding + star grounding would work better

Possible ground loop maybe? I've heard that makes it buzzier, but I'm not sure of what magnitude (I bring this up half because it fits, half because I feel I might have one, although it doesn't buzz that bad)


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#14
Quote by ikey_
my solder joints? all are stong i know that. however why do they need to be round? i mean i suppose i could clean them up and make them round. i didnt think that was nessesary. i just trimmed the excess and made sure all joints were secure.


solder joints should be round and shiny. when you melt the solder on it should make a nice round smooth surface. sometimes if the joint has been disturbed while cooling it'll cause a cold solder joint (a solder joint that doesn't make a good electrical connection). after soldering something just let it sit there and cool (doesn't take long) don''t blow on it, or move it.

if the tip of the iron or the parts are dirty or corroded then the solder will be very hard to get to stick and if you do get it to stick it might be a cold joint.


as to the grounding issue, there is no issue. if the hum goes away when you touch the bridge, strings, etc. then it's doing what it should.

If it seems to have too much hum it'll need to be shielded (many guitar companies use a shielding paint on the cavities, and the covers will have a conductive tape). you can use aluminum or copper tape (preferably with conductive sticky side cuz it's easier) or even gluing foil down. this shield is grounded, and blocks external noise. you can find more info on google.

it might also be caused by a ground loop, which could be fixed by using star grounding, but I'm not sure if that's correct or not. I've heard that star grounding should be done on guitars, but I've also heard that it makes no difference.

also, where is your pickup switch located? if it's up at the top horn with a long stretch of single conductor wire that could also cause a little noise. shielded wire (insulator, twisted or braided wire around another insulator which contains a wire) could help in that case
#15
i will check all my joints. do the ground even need to be shiney?

the switch is at the bottom and close to the rest of the wires. i can try tape, that is quick and easy.

the grounding is an issue - because my otehr guitar doesnt do it. if factory guitars dont hum, and mine does, there is an issue even if it stops when i touch the bridge. have you ever bought a new guitar that hummed and stopped when you touched the bridge? no. cause nobody would buy one.

i dont know what a ground loop really is, but i can research it. can you give me a simple explanation?

i atribute the pickup thing to my wiring one better than another, or perhaps the ground is better than another. i know one of my grounds (a ground that includes about 4 wires on teh back of the volume pot) was very hard to get to stick, and is NOT shiney. it was a hastle, and took a long time to get to barely stick.

could that be it? a poor ground connection? i will try again.

how do you get solder to stick well to a shiney flat surface like a volume pot? i try solder paste, but it just get hot, melts, and runs all over the place. it seems like getting it to stick is just luck, as i have to try like 10 times.

any advice?
#17
Quote by ikey_
i will check all my joints. do the ground even need to be shiney?

Shiny is best.
Quote by ikey_
have you ever bought a new guitar that hummed and stopped when you touched the bridge? no. cause nobody would buy one.
Ever heard of "Epiphone"? People buy those.
Quote by ikey_
the grounding is an issue - because my otehr guitar doesnt do it. if factory guitars dont hum, and mine does, there is an issue even if it stops when i touch the bridge.
It does sounds like a grounding issue. However, it may or may not be possible to make this guitar as quiet as your other one. Different pickups, different wiring, etc.
Quote by ikey_
i dont know what a ground loop really is, but i can research it. can you give me a simple explanation?

In short, when there are multiple paths to ground connecting components. It can create an antenna effect, which increases noise.
One way to eliminate this is a technique called "star grounding", where you have a one single point where all components connect to ground, (rather than grounding some things to pots, then connecting the back of pots to each other, etc).
Quote by ikey_
how do you get solder to stick well to a shiney flat surface like a volume pot? i try solder paste, but it just get hot, melts, and runs all over the place. it seems like getting it to stick is just luck, as i have to try like 10 times.
Like Forsaknazrael said, rough up the back of the pot with sandpaper. It is really hard to get solder to stick to the back when it is smooth.
Quote by ikey_
any advice?
Shielding the cavities, as several people have recommended, can work wonders.

One last thing: connect that bridge ground wire to the wraparound bridge you are actually using, not the tremolo that is just there for looks. You want the strings grounded too.
Last edited by cedricsmods at May 19, 2010,
#18
oh. damn. i think i have ground loops. ok i will redo my grounds, chekc for shiney joints, and rough the back of the pots.

however, how do you get a wire from the internals to ground to the bridge OUTSIDE the guitar? i would rather not have a wire hanging out of the guitar.

ive never played an epi that buzzed. atleast my les custom doesnt. its perfect.
#19
the ground wire's typically attached to the stud or post of the bridge in that kind of situation

..it might be a little difficult to get a wire there without some very creative drilling though :/
#21
well, the wire is long enough. that i could do its route a hole in the pickguard just large enough for the wire to fit through, and then to the bridge post. with my guitar, you could do so almost without being able to see it from the unknowing eye (i would know where to look of course).

i will A - make all joints shiney

B - remove ground loops (or make sure there are none)

C- if those dont work will route wire to bridge

and if those things dont work....well hell my darn guitar is just going to hum.
#23
nope. all wires are acounted for. i know cause the only wires that remained were the pickups and the jack wires running to the bridge cavity. i tried to work with the old wiring, but it was just to old, worn, and unorganized.

there is only 1 wire to the bridge. if i could guess, i ran a ground wire from each pickup wire to the back of the volume pot....which i guess would create a circle between the pickup switch and the volume pot. i am guessing that is a ground loop.

so what i will do is solder the two estra pickup wires together, and run one ground wire from the combined pickup wires to the volume pot.
#25
ok. so i need to get rid of the bridge ground, or use the volume pot. and make sure no 2 wires from the same location are going to the same place ie- making a ground loop.

so basically....i need to star ground all wires to 1 spot.
#27
oh my bad. i meant to the disfunctional trem assembly from the output jack. correct there is no bridge ground.

right now, i have both grounds at the output to teh trem, and grounds on teh back of the pots.

http://www.guitarelectronics.com/product/WD2HH3L11_00/Guitar_Wiring_Diagram_2_Humbuckers3Way_Lever_Switch1_Volume0Tone000.html

i am following this. it says all ground to volume. the original wiring had a wire in the trem. im no electrical genious, so i kept it that way. now i am realized that that is am issue.

in addition, like i said, i may have created some ground loops. so i need to get rid of those, and pick a spot for 1 ground. right?
#28
Can you take some pictures of the wiring? It'll really help with diagnosing the problem.
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#29
ok revelation -

the hum completely goes away 100% dead quiet with the tone knob all the way down. with it up, there is hum. both pickups, nomatter what grounding method. what does that mean?
#31
sweet. but why does my guitar hum and other guitars dont?

i dont understand. everybody is telling me im doing things right, but my guitar still hums. wtf.

can i change that situation so the hum gets filtered out 100%? different capacitor?

i also found out i wired the neck pickup poorly, it cuts out randomly. gotta fix that.
#32
It may be beneficial to you to just take everything out and re-wire it.

You will want to follow This diagram. It has everything, including the pots and switches grounded. The wire coming from the bridge should be exactly what it says, a wire, soldered to the bridge, that goes into the control cavity.

And this may still hum, the ways that were suggested, and will help the hum a bit, is to shield the cavities and star-ground it. Star grounding is picking one spot, and soldering any grounded thing to that. If you do shield it, solder a wire from your shielding (copper tape, aluminum foil...) to your grounded point.


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#33
that SD diagram has some differences. i will take that into acount and try again tonight. thanks.
#34
That diagram is correct, the way you did it may have been different, but since you haven't given us any information as to your wiring, such as a diagram or picture, I don't know if your alternate wirings even work as they should, they may even be the cause of the humming.


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#38
that is very similar to the other SD diagram .

for the record, it is a 2 way toggle switch. thats what was in the guitar before, thats what the guy at the store gave me, and i thought about it and didnt care, ill take a simple guitar.

after i get this wiring done right, i will consider installing a boost lead switch, which bypasses the tone/volume...basically making your sound loud and edgy when the switch is flipped (like maxing out your tone and volume). with my configuration is would be really easy. literally adjusting/adding 2 wires and the switch of course.
#39
Yes it is very similar, it is just a different switch.

So what kind of 2 way switch is this? A DPDT? how many lugs does it have?

And yes, it would be a very simple mod, just a SPST, with the wire from the switch output to the pole, one throw going directly to output, and one throw going to your vol/tone. Take in mind that bypassing them will make it very bright, and very loud, but enough about that here, if you want to discuss it, go to the Ultimate-Wiring thread.


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#40
its a 2 wat switch, 3 lugs. heres some pics:

this is the SD wiring i completely redid this morning. same buzz. the SD diagram and the other one i use are the same, with a few wires and grounds rearranged.
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