Guitar Hum, HELP!!

Sleeping Martyr

New member
So my Les Paul has a bad hum that goes away when either the input jack, tailpiece or switch are touched. I know its a bad ground somewhere but I don't know where. I've soldered and re soldered everything, replaced the switch and input jack but still theres the hum. I've even disconnected both pickups completely and there it is still, but it goes away when metal parts are touched. The ONLY thing I haven't seen is whether the bridge ground has come loose from inside the body, if possible I just don't want to have to pull the tail piece stud out as I've never done that before. Its in all positions by the way. Ideas?? Could it be a bad pot?? Please help guys
 
Re: Guitar Hum, HELP!!

Plugged straight into the amp? No effects at all?

Lets just say I had an EMG based rig that buzzed like a swarm of bees. It wasnt the guitar - more like daisy chained power + a florescent light transformer.
 
Re: Guitar Hum, HELP!!

Plugged straight into a variety of amps with different cords, all the same result. Just checked everything with the multimeter and all the connections seem good too, I don't know
 
Re: Guitar Hum, HELP!!

I'm baffled, every connection seems good and when I plug my dean ML (with a Dimebucker in the bridge) its super quiet. My SG also is making a similar noise to the Les Paul. Would a bad pot cause hum like this?? I wouldn't think so as its a grounding issue which dissapears when you touch the metal but maybe. Could a lack of shielding in the cavities cause it?? I know the Dean cavity is better shielded, thoughts??
 
Re: Guitar Hum, HELP!!

I thought so too, but I touched a multimeter to the pot its grounded to and the bridge itself and got a strong reading
 
Re: Guitar Hum, HELP!!

Every ground according to the multimeter is a perfect 0 except for the bridge ground which is a .001, yet the multimeter holds a continuous beep. Would that reading even matter??
 
Re: Guitar Hum, HELP!!

I would disconnect components one by one and test every time. Takes time but it helps when you get lost sometimes.
 
Re: Guitar Hum, HELP!!

How bad is it really? I mean between songs you turn down anyway? And during them youre playing, so how much of an issue is it?

Ive had guitars in the past with the same issue and replaced all the electronics and stuff only to find its still there. I just gave up worrying about it.
 
Re: Guitar Hum, HELP!!

Are you sure you don't have the output jack wired backward?
 
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Re: Guitar Hum, HELP!!

try to get us a sound clip of that noise. holding it to go away and then letting go so we can hear the noise.
 
Re: Guitar Hum, HELP!!

Thanks guys, I thought I had it fixed but at band rehearsal it came back, only now its gone even when I touch the strings. When they (or any metal) is being touched then theres nothing, both my Les Paul AND SG. Maybe I didn't have it fixed before and didn't try not even touching the strings. I would consider leaving it but when I was singing backups I could feel microscopic little shocks on my lips, like a small buzz . . . or maybe my new Movember mustache was getting caught in the mic haha. Does that narrow anything down??
 
Re: Guitar Hum, HELP!!

Try it through another amp? Might be the ground on the amp is dodgy. Sounds like its a dangerous situation.
 
Re: Guitar Hum, HELP!!

You have buzz, not hum.

Hum will be 50/60 hz and could be ground loops, dimmers, etc. picked up by the pickups.

If it goes away when you touch the strings then it is buzz, and is caused by any unshielded wiring in the cavity. Check by turning down the tone knob, the buzz should get less if this is the problem.

Nothing to worry about unless it really bothers you, then you might need a rewire and good screening.
 
Re: Guitar Hum, HELP!!

Thanks, I noticed that the Les Paul (and SG to a lesser extent) have little to know shielding done in the cavities. Would that help reduce it you think??
 
Re: Guitar Hum, HELP!!

After rebuilding an iceman with new SD pups it had the same problem. I shielded the cavity with copper and it did help a little bit, but I think I just need better quality wiring, especially the wire run up to the switch knob.
It doesn't bother me enough to need to do it though.
 
Re: Guitar Hum, HELP!!

Small shocks on your lips when singing into a mic? Park that LP now, and don't pull it out 'til you solve the prob.

Google "Keith Relf" and you'll see why.

The only other possibility that comes to mind for me are perhaps the pups themselves are bad. Maybe time for some new SD's... :D
 
Re: Guitar Hum, HELP!!

Certainly take a look at that mic problem dude, it doesn't sound good.

It might be polarity wrong at the mixing desk or even a low 48v phantom needlessly switched on with a bad mic. Depends whether the mic thing happened with the clean sounding Dean or not.

If the mic shock happens with all your guitars, make sure your guitar rig is grounded everywhere, with no ground lift on the speakers.
If it all seems ok then park up the mic.
 
Re: Guitar Hum, HELP!!

Wow that Keith Relf thing is crazy! I think I'll just take it in and get her looked at, I don't want to park it but I can't find the problem and don't want to die haha. I just wish I could figure it out on my own, does wire type make a difference??
 
Re: Guitar Hum, HELP!!

Look man, a guitar does not produce dangerous electricity on its' own........

For Relf, and maybe your mic thing, it is either your non grounded problem rig or dodgy mic which could be dangerous especially if the guitar is wired backwards and the strings are somehow live to then ground through the mic (a guitar wired like this gets noisier when you touch the strings, not quieter, so doesn't apply to you)

When either the faulty rig or mic is sending live current to shield ( maybe through you and the strings!), then a correctly wired guitar might transfer this through your fingers to ground.
If a bad mic, then through your lips and a good guitar ground, or if a badly grounded rig, through the mic via you and the strings. This is normal for the electricity path, but is dangerous unless you make sure that you cannot become the optimal pathway for any bad electrics.

In all cases, there needs to be a bad case of wiring external to the guitar, and you need to know where that is, be it your rig or mic.

My guess with your mic thing would be a 48v signal phantom being sent to the shield (wrongly reversed polarity) of the mic which then travels through your lips to the guitar ground through your fingers (so long as the guitar is wired correctly).

You need to test this with all your guitars and eliminate the problem with regards to your rig /guitar / mic & desk, before something bad happens. Better safe than sorry, and remember the real problem of rogue current would not originate from your guitar.

Back to the quieting of the strings by touching them thing, there is a myriad of internet stuff out there on that exact problem.

Yes, good shielded wiring makes a difference.



Stay safe dude....
 
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