How do I get my guitar to stop humming?

Question

My #1 guitar hums like crazy whenever I play it. If I plug in another guitar with the same amp and cables and everything, in the same room, standing in the same spot, no hum, just the faint hiss that a Mesa Triple Rec always has on the distortion channels. But when my guitar is plugged in ... crazy amounts of hum, so it's definitely the guitar, not the cables, amps, outlet, lighting, nearby electronic devices or will of the gods for anyone who is already typing up their response that I should turn off my TV or fluorescent lights. BTW its a Les Paul guitar with Seymour Duncan humbuckers, not a single coil guitar, so that's out too.
Now here's the rundown. This guitar has always hummed. It hummed with the factory pickups and electronics. After purchasing I took it to my luthier and had those factory pickups replaced with passive EMG pickups, and the hum was still there. Next I had him remove all those cheap korean made electronics and wire in good ol' made in the USA Switchcraft pots and pickup selector switch ... and the hum continues. I set it in my mind it was just the EMG pickups and played on for about a year. Then I recently decided to replace those EMG pickups with Seymour Duncans, and still, the buzz is there.
Now, I love this guitar and the way it sounds, and I'm going to use it live and in studio regardless of the humming, and I've gotten pretty good at footswitching in and out of the clean channel and rolling the volume knob to get in and out of guitar parts without the audience hearing the buzzing (the buzz is way less noticable on the clean channel and zeroing the volume on the guitar kills the noise), but it's just really irritating. My luthier says he's running out of ideas and I have long since run out. No matter the venue or studio or practice space I'm at, I deal with this noise.
So, for anyone still reading this complaint that has a strong knowledge of guitar electronics here's what I can tell you that may help you help me. As I stated earlier, it is DEFINITELY in the guitar. I can unplug my #1 Les paul (now with Seymour Duncan humbuckers) and plug in my #2 Les Paul (equipped with passive EMG's) and there is no hum. Plug the #1 guitar back in ... hum. The only piece of electronics left that has not been replaced is the jack, which my luthier feels isnt causing the problem. If you zero the volume knob then the hum dies (either pickup), but here's where it gets interesting ... I had my luthier install a touch-button killswitch at the same time the seymour duncans were installed. The killswitch perfoms as expected (cuts the guitar signal) but DOES NOT kill the hum. As a matter of fact, if the volume knob is at zero (no hum) and you press the killswitch the hum returns, then goes away when the killswitch is released. Please bear in mind that the hum was present before the installation of the killswitch, so it is not the culprit. Also, if the volume is up (hum present) and you press the killswitch, the hum doesnt go away or drop in volume at all, but the sound of it changes slightly, sort of going from the bright hiss to a more nasal sound, but at the same volume and intensity. I'm at the end of my rope and just want the guitar that i love so much to stop humming, and I cant figure out how. As far as I know there is no way that the wood can cause a hum, and it's about all that's left that hasnt been replaced. If anyone out there can help, please do...

Answer 1

I'd start with the grounding problem. If its a Les Paul, make sure its grounded to the posts correctly. Furthermore, a new jack is $10. Just change the damn thing if you have gone this far with changing everything else. Also, have your guitar tech/luthier resolder all the joints. Sometimes you can have what is called a cold solder joint and that joint although making contact, will have a real crap connection. Its likely there is a joint like that either on your output jack or your bridge (ground). Also, you said things were replaced. Were wires replaced or just resoldered? If a wire was nicked by a soldering iron, it may have a buzz. Also, some wires are just crap... they should have been replaced with shielded wires if everything else was replaced. If that doesn't work, the last thing I can say is to shield your guitar. They make nickel based paint and copper foil tape to do that with.

But check for the cold solder joint, bridge ground and replace that $10 jack... that hopefully should clear you up. All your solder joints should look shiny, and the metal wire should make a direct connection with the metal it is being soldered to. And check all the wires insulation as well as making sure all the tones and volume pots do not have cold solder joints.

Answer 2

It's just bad, noisy wiring. In general, guitars have really poor wiring. Even most high-end guitars have wiring that wouldn't pass QC in a Happy Meal toy. So... bad wiring = lots of noise Take it into a professional and ask them what they can do about it. It could be a really simple fix, or it could be something that requires a bit more work. It's impossible for me to say without testing out your actual gear.

Answer 3

It's probably just crappy wiring in your guitar. Is it properly grounded? Most likely not. Even some "high-end" guitars come with really poor quality wiring.



The basic circuit that most people know how to install in a guitar is absolute crap. Look up a wiring diagram on Seymour Duncan... on DiMarzio... factory wiring for Ibanez, Fender, Gibson... all of them tell you REALLY CRAPPY WAYS to wire your guitar.



Anybody that knows anything about electronics will tell you that the "guitar circuit" is incredibly poor quality and wouldn't pass QC in a Happy Meal toy. Lots of luthiers and guitar techs don't really know **** about electronics. They know what they learned from fixing guitars, not from reading up on how electronics work. I rewire EVERY guitar I buy, and often rewire my friends guitars too. My wiring is far superior to what you get from the factory because I actually know what I'm doing.



If you can open up the cavity on your guitar and send me a picture of the wiring, I could tell you exactly what's wrong with it, as well as how to fix it.

Answer 4

Crap. that sucks. you might have a grounding problem inside of the guitar. I had a similar problem and I took it back into where I bought it and luckily I had a warranty so it was replaced. I know it can be fixed but they really have to go in there and replace some parts.