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why does my guitar make noise when i dont have my hands on the strings?


mr.chEn

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why does my guitar make noise when i dont have my hands on the strings?

 

also.. when i turn down the volume pot, i can still hear a slight hum. I just put in a pair of 57 classic pickups. does that mean theres a bad solder connection somwhere? and where could it possibly be

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well the thing is that when i plug my tele into the same amp and turn my guitar volume all the way down theres no hum

this phenomonon is limited only to my les paul

 

so to summarize, theres a hum when my volume pots are down, and an even louder one when my hands are no longer touching a string

 

could it be something to do with the wire designated as "ground from bridge" on many wiring diagrams?

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well the thing is that when i plug my tele into the same amp and turn my guitar volume all the way down theres no hum

this phenomonon is limited only to my les paul

 

so to summarize' date=' theres a hum when my volume pots are down, and an even louder one when my hands are no longer touching a string

 

could it be something to do with the wire designated as "ground from bridge" on many wiring diagrams?[/quote']

 

It could be. Ah, you do have that wire run up through the bridge post holes, so it makes contact with the bridge/string assembly, and then soldered into the ground? It could also be that THIS set up pickups up more RFI. You could even try swapping the 1/4" cord end-for-end just to see if that's it. Try a different cord, or a wall socket on a different socket and see if the hum changes. No way for us to know, all we can do is offer suggestions and wait for you to report back after trying them.

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why does my guitar make noise when i dont have my hands on the strings?

 

also.. when i turn down the volume pot' date=' i can still hear a slight hum. I just put in a pair of 57 classic pickups. does that mean theres a bad solder connection somwhere? and where could it possibly be[/quote']

 

There's a wire that connects the tailpiece (and through that, the strings) to the ground of the guitar circuits. When you touch the strings, you are grounding out that connection through your body. When you remove your hand, the ground connection is now 'floating' and it hums more.

 

The volume thing... did you re-wire the volume pots for 'independent' volume control? I'm pretty sure that this method will give you hum when the volumes are turned down to zero. You don't get nuthin' for nuthin'.

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well, i went back to resolder the bridge wire.. right now its connected to the neck pickup volume pot, and im still getting hum! this is making me very frustrated.. im almost certain its got a good solder connection.. I still have a problem

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it is going away from the strings.. infact, the hum even goes away if i touch metal parts on my AMP.. which i find odd..

but if i dont touch a single metal part of the guitar or amp, it will hum.. almost as loud as normal single coils

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I think I've already explained why this happens. You're getting all bent out of shape over a non-problem, since you are usually touching the strings at some point when playing. Any guitar will buzz like a pig when you let go of the strings. What happens when you're not playing doesn't matter. Put the amp on standby.

 

Otherwise, re-check your wiring.

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well.. the odd thing is that this hum is also present when both volume knobs are down to zero.

 

im also just unhappy over the fact that the wiring isnt perfect, and that its not the best that it can be

 

edit- under further inspection it also seems that i can touch my amp and that can also cancel the hum. with the assumption that my hand is acting as ground, could it just be bad solder connections cauing this??

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I just put '57's in my Wilshire and had the same hum that would go away as you touched anything else in the circuit. As Rot says it is a floating ground. The way I would narrow it down was using jumpers to locate the "float". When the offender is grounded properly the hum disappears. Do make sure you test the sound by strumming the strings because you can ground the signal as you go through this process. This also may require removing the ground wires one by one until you find the mis-wired one and where it should be located in the circuit. (that ought to be a trial and error last resort as I think you can follow the circuit and see where the problem is located)

 

A question: Are you using shielded cables? If you are, the location of the shield grounding can be an issue. It all must come eventually to a common ground or you get the hum. My hum was being generated from the switch shield which I miss located.

 

The grounding method I used is to ground each tone pot to the associated volume pot and then directly and individually from each volume pot to the jack ground. The switch shield and ground went to the nearest volume pot ( I recall that being the neck). I had the switch shield to the jack positive and it made an antenna out of the shield LOL! It was the noisest thing you ever heard. Once I relocated the jack shield, it became quiet as a mouse and sounds great.

 

Now the amp will have a little hiss, but shouldn't be a major hum I don't think. I am using a Marshall DSL 50.

 

BTW, also look at how the pups leads are done; a excess of pup lead wire can get grounded in the box at a place where it shouldn't.

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well' date=' i went back to resolder the bridge wire.. right now its connected to the neck pickup volume pot, and im still getting hum! this is making me very frustrated.. im almost certain its got a good solder connection.. I still have a problem

[/quote']

 

You didn't mention the model of the Epi LP, but I have a Epi LP Custom (ebony) that

was made in the Saen factory in Korea. I bought it on E-Bay (new) so I had no recourse

but it had a hum when I plugged it in as well. I checked out the wiring and found

that they had used unshielded wire from the p_ups to the 3 way. I replaced the

unshielded wire with shielded and the hum went away for good...now it is very

quiet plugged in (and not played of course).

 

I don't know if mine was a factory mistake, but it definitely was not right for a high

impedance circuit. The two runs to the switch from the vol pots and then the output

of the switch to the jack are almost 4 feet. That is a lot of unshielded wire.

 

Check yours out to see if that could be the problem.

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why does my guitar make noise when i dont have my hands on the strings?...

 

 

I also have a humming issue with my Roland Cube-6o each time I plug in the Peavey JF1 EX ( i.e. hollow body ) . However, the humming does not occur if I turned the volume knob on the Roland down to its minimum before turning on the Roland and plug in the guitar ! I do not know why it works this way ? Any plausible explanation ? ( The Peavey has never been rewired after I bought it brandnew ) .

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another sign i noticed on my friends little cheapie crate amp, is that i get some sort of popping noise every once in a while, in a random fashion. its a very faint pop that is present on every channel

 

something also odd is that the hum is substantially less on the middle pickup position than either the bridge or neck by itself.

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Heres a question.. when i wire my pots together for grounds.. do they go THROUGH the lug i bend down? or over it?

 

 

edit- Alright, heres some photos. i know i used a S*** load of solder, but i tried to take out all the flex and make it nice and shiny.. but here it is.

DSC01040.jpg

DSC01041.jpg

 

 

 

NOTE: the green wire is the ground from pickup selector,

red is pickup selector to bridge p/u vol pot

small white wire is pickup selctor to neck vol pot

big white wire is p/u selector to input jack.

black are all the grounds, as usual

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Mr Chen, Take a look at this Seymour Duncan diagram. You connect the red and white wires together. That couples the coils to be wired in series. Green and bare (the shield) connect to the ground loop. Black connects through the volume pots to the three-way switch and then out to the output jack through the common center connection on the three way switch. The tone caps connect from the center lug of the tone control to the case of the tone pot. You have the caps bridging from center lug of the tone pot to the center lug of the volume control..

 

I think you need to carefully compare the diagram in the link to your guitar. I'd print it out in color and compare it. There's a PDF printable version if you click on the picture. I think that you have multiple wiring errors in your picture. If you re-wire it carefully to match the picture, you will fix your problem.

 

http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=2h_2v_2t_3w

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Follow Dave's advice. There is also a Les Paul wiring diagram on Specialty Guitars that shows exactly what you are trying to do, although the connected grounding isn't shown; it is very helpful. I believe I found one on the Gibson site. Also, from the picture it looks like your pickup ground is soldered over the entire pickup lead. I always unwind the braid back a little (it is a pain to do, but well worth the effort) and then twist it into a wire lead. Then when you solder you won't have to worry about melting through to the pickup lead. Depending on how much heat is applied, this could be a problem.

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Mr. chEn,

Follow the wiring diagram from the Specialty Guitars site and what I gave you above and you cannot miss. I think the only thing I neglected to mention was making sure your bridge ground is done and others have covered that well. FWIW, I have done what you are attempting twice and have excellent results.

 

Your '57's have one cable with a braided shield from the p[ickup so you don't have the colored wires from the pickup, but you will need to follow the colored wires from the jack to the switch and pots, etc.

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Okay, I think the hum is normal. Here's what I'm thinking:

When you use your tele and turn down the knob, the hum goes away because you're used to the loud hum from the single coils. With the les paul, when you turn down the volume you it only gets a little quieter. I think it's all relative to what the amount of hum was.

 

To be positive that the hum is from the guitar, use a volume pedal. Turn the knob down and then turn the volume pedal down. If the hum is still there, it's from the amp or pedals after the volume pedal. If it's not there, it's from a pedal before the volume, or the guitar.

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