Guitar hisses and stops when I touch the strings

[09 BB King]

I am have that classic problem of when I do not have my hands on the strings plugged in to my amp I get a hiss and when I touch the strings it goes away. It is not 60hz hum. It checked it with both my guitar and bass amp to rule out the amp. I know it is a bad ground somewhere, but I have soldered, unsoldered and re-soldered about 5 times now and it wont go away. When I have my volume set to about 2 it is not too noticeable, but at about 4 it really starts to annoy me. None of my other guitars do it, I get 60hz hum with singlecoils, and I expect that noise to be present. I am an electrician and have been soldering for years. This is about the 5th guitar I have soldered from scratch. It is a used Gibson LP Studio 60's Tribute body and neck I bought online. I routed the P-90 holes for hums and put a set of SD Slash Sig pups in it. Everything is brand new except for the guitar and neck. I ohmed every ground connection out an they all read less than 1 ohm. I currently have it unsoldered again, and may wire the pups right to power to see if it is still there. Could I have bad pots, or a bad switch or a bad jack? It may be one of those components. I hope it is not the pups, cause at about $180 a set that would infuriate me.

Any thoughts?

__________________
'57 Gibson ES-225TD with original P-90's
'09 Gibson BB King Signature Model with original Gibson 490's
'11 Gibson Les Paul 60's Tribute with Seymour Duncan Slash pups
'10 Gibson SG Faded with a Gibson Tony Iommi pup in the neck and a Gibson Angus Young pup in the bridge
'05 Fender American Series Strat with Fender Eric Johnson pups
'07 Fender Highway 1 Telecaster with Fender Texas Special Pups
'12 Warmoth Jazzmaster with Seymour Duncan JM Antiquity pups
'00 Martin D-15
'95 Fender American Standard Jazz Bass with original Am. St. pups and a Warmoth neck
'11 Fender American Special Jazz Bass with original Am. Sp. pups and a Fretless Warmoth neck.

 

[Maynardo]

Re: Guitar hisses and stops when I touch the strings

is the guitar properly shielded?

 

[GuitarDoc]

Re: Guitar hisses and stops when I touch the strings

Check the ground from the bridge with your meter. Also, make sure all components are grounded, inc switch.

 

[jake_xms3_punk]

Re: Guitar hisses and stops when I touch the strings

although it probably is a grounding issue with the guitar, it could be the room you're in / socket you're amp is plugged into. have you tried the amp in a different place? I'm only saying this because in my house I have the same problem as you but in practice and gigs its not a problem.

 

[uOpt]

Re: Guitar hisses and stops when I touch the strings

One likely explanation is that the baseplate of the humbuckers isn't connected to ground.

With 4-conductor wires people sometimes only wire the 4 inner wires, but not the shield of the cable, the 5th strand in there that is blank. The result will be behavior like this.

 

[09 BB King]

Re: Guitar hisses and stops when I touch the strings

Thanks for all the replies. Here are the answers.

The large solid uninsulated ground wire was in place when I tapped the mounting screw pieces that hold down the Tailstop was there and I have ohmed out the Tailstop, Bridge and Strings to everything that gets grounded ie switch, pots, jack.

The SD Slash pups I bought are two conductor with the metal jacket and then a single inner conductor.

The ground is connected to the switch on its own side opposite the 4 solder connections for the pup switching.

Not sure if the guitar is shielded proropery.

None of my other guitars hiss with the same amp. They area all dead quiet, exect for 60hz hum on singlecoils.

 

[~Vintage~]

Re: Guitar hisses and stops when I touch the strings

You might want to get some copper shielding tape and coat the inside cavities with it. This will keep unwanted hum out of the signal chain.

 

[Varg]

Re: Guitar hisses and stops when I touch the strings

One likely explanation is that the baseplate of the humbuckers isn't connected to ground.

With 4-conductor wires people sometimes only wire the 4 inner wires, but not the shield of the cable, the 5th strand in there that is blank. The result will be behavior like this.

Seriously? This is the first time I've ever heard that, I normally just pull the shield part out of the way and ignore it! Doesn't it touch the bare wire anyway, I cant picture it now.

 

[~Vintage~]

Re: Guitar hisses and stops when I touch the strings

Seriously? This is the first time I've ever heard that, I normally just pull the shield part out of the way and ignore it! Doesn't it touch the bare wire anyway, I cant picture it now.

Yeah but you want to take that shielding wire and solder it to one of the pot casings or else your not grounded.

 

[Varg]

Re: Guitar hisses and stops when I touch the strings

Yeah but you want to take that shielding wire and solder it to one of the pot casings or else your not grounded.

But if the shielding is touching the bare wire, which is soldered to a pot, isnt that doing the same thing?

 

[09 BB King]

Re: Guitar hisses and stops when I touch the strings

I think I figured it out. I soldered only one pup, the neck pup, through the switch and directly to the hot of the jack. I then soldered the braided sheath of the pup to the volume pot and soldered the bridge ground and the negative of the jack using only the metal of the pot as a common ground bus. So all I had in the circuit was 1 Pup, switch wired full open no volume control. And guess what buzz. Then I wired the pup without the switch and the buzz went away. I guess I will be buying a new switch manana. Never would have guesses it was the switch.

 

[uOpt]

Re: Guitar hisses and stops when I touch the strings

Seriously? This is the first time I've ever heard that, I normally just pull the shield part out of the way and ignore it! Doesn't it touch the bare wire anyway, I cant picture it now.

You misunderstood.

If you connect the bare wire to ground you are all set.

But I have seen several cases of wiring done ignoring the bare wire, they just cut it off. Then the wire shield isn't grounded which isn't too much of a problem since every Strat runs that way. But neither is the humbucker base plate and that has more of an impact.

 

[~Vintage~]

Re: Guitar hisses and stops when I touch the strings

But if the shielding is touching the bare wire, which is soldered to a pot, isnt that doing the same thing?

Yeah but then your just hoping for a ground. I like to do the job right the first time and know it's all grounded.

 

[09 BB King]

Re: Guitar hisses and stops when I touch the strings

I now wired it back up and it should be, but with no switch in the circuit. I took the hot from the jack and split it to each volume pot terminal and faked out it having a switch. I just have both pups always on right now, but at least I have no buzz and volume and tone control. I usually play with both pups on most of the time anyway. I will get a new switch later today or tomorrow. It now sounds like it is supposed to. It drives me crazy that such a simple thing can take a while to figure out. I could have had it done sooner, but after I get my butt kicked for a while I see my other guitars in there stand and I know they don't buzz, so I pick them up and play them and curse the evil one that buzzes.

 

[Varg]

Re: Guitar hisses and stops when I touch the strings

You misunderstood.

If you connect the bare wire to ground you are all set.

But I have seen several cases of wiring done ignoring the bare wire, they just cut it off. Then the wire shield isn't grounded which isn't too much of a problem since every Strat runs that way. But neither is the humbucker base plate and that has more of an impact.

AH, ha right, okay so I've not been doing it wrong. On the other hand, I was thinking this might be a simple fix in any guitars I have that buzz in any way :lol:

 

[Gearjoneser]

Re: Guitar hisses and stops when I touch the strings

Thanks for following up with the solution. Too many threads about problems never get resolved.

One of my guitars has had a grounding issue for awhile, and this thread will help me troubleshoot it. I have to check if one of the baseplates on a homemade hybrid didn't get connected to ground. If it's not that, then I'll bypass the switch like you did.

 

[09 BB King]

Re: Guitar hisses and stops when I touch the strings

No problem. As an electrician I have a pretty structured way I troubleshoot. I like to think I use logic and reasoning and the readings I get with my ohmmeter to find the problem. Sometimes I just get stumped. I had a Ric 4003 Bass I bought in ebay and the guy who sold it to me used to two thumb screws that raise and lower the mute for strap buttons. Being my first and only Ric, I did not know the metal plate that the foam rubber is mounted for the the mute is how Ric grounds the bridge via a wire connected it and the thumb screws tighten down on the bridge. So my first two hours with my 4003 I had waited years to get was spent solving a ground issue. Luckily I got on Ric's website and looked at the wiring diagram and saw the mute was grounded and that clued me in. There really isn't much to a electric guitar. Pickups, jack, switch, wire, pots and caps.