Just about every electric guitarist or bassist has experienced “the hum.” It seems ubiquitous, like no matter what you do, how you stand, what you play, the way you hold your mouth, it’s there. It’s not offensive, but it’s noticeable, and right when you think it’ll never, ever stop, you touch your strings or the jack, and it does.
A guitar hum stops when you touch the jack because you become part of the ground, essentially. Humming is generally caused by how the components in the guitar are wired, which can be fixed by using humbuckers, shieldings, or noise suppressors.
In this article, I’ll provide a fuller explanation about why a guitar hum stops when you touch the jack alongwith possible solutions for each reason. Should you have other humming problems, I’ll also explain some other possible causes for hums and those quick fixes.
Why Electric Guitars Hum
That’s the big question, isn’t it? And it IS a big question because guitar hum can come from any number of sources. Between your amp, any pedals, processors, and other effects units, your cables, and your actual guitar and its solders and wires, there’s a seemingly limitless amount of potential hum producers.
Most likely, your guitar hum stems, at least in part, from the way we build electric guitars. There may be other electrical issues at play— you may have a grounding problem, a loose wire, or a solder that’s come loose, but even in those cases, you’re still dealing with an electrical issue.
If you’re in a recording setting, that hum could present an issue. No matter the source of the hum, you’ll need to know the culprit before you can do anything about it. Isolating the offending item can be time-consuming and painstaking, but once you’ve found that it’s your guitar, you have solutions to try.
However, you’re here because the hum you currently fight in rehearsal and onstage mysteriously disappears whenever you touch the jack (or any other metal on your ax, including the strings). Let’s take a look at how the same electricity that amplifies the sound of your strings also causes interference, buzzing, and humming.
The Ground (and Ground Loop)
As part of its very nature, if you will, electric guitars are designed to hum the way they do and also to stop humming when you touch the strings or other metal to it. With all that electricity running through wires, pickups, and jacks, guitars “naturally” hum because of that electrical energy.
Early electric guitar makers quickly realized that touching the metal eliminated the hum, so they began attaching a wire to the bridge.
This is possible because all the components in your guitar are wired together. When you look inside and see all those wires soldered here and here, you can see that the electricity has many places to go. There’s lots of electrical noise going on there, and by wiring the bridge, guitar makers made it so that when a player touches it or the strings, that player becomes part of the ground, and the hum goes away.
So if you’ve got a low, relatively soft hum that goes away when you touch any metal on the guitar, there’s probably not any major issue plaguing your instrument or your amp setup. However, even the softest hum can be a problem in the recording studio, and we’ll address some possible solutions to it shortly.
You may also have a ground loop issue. A ground loop occurs when the electricity coursing through your guitar sees two or more paths it can take toward a ground. Everything has to be grounded, so that’s another thing to check out: When you look inside your guitar, be sure the ground wire (the black wire, likely) connects to all the attenuators and switches.
Any component you find not wired to that ground wire remains ungrounded and will cause some hum when the guitar gets plugged in.
How To Fix Guitar Hum
If the hum just comes from the electricity coursing through your guitar and you still want to get rid of it (or try), there are some steps you can take. Two of them, however, are not for you if you know nothing about electric wiring or tinkering around. The third can get pricey. Let’s take a look.
Humbuckers are pickups that, as one might imagine, buck or eliminate hum. If you play a Telecaster with its two single-coil pickups, you’ll get some overall buzz here and there every now and again (and again and again). That’s the nature of a single coil. It’s one or more magnets wrapped in a single coil of copper wire, and it’s prone to buzz and hum.
A humbucker is, at its heart, two single coils wired together. It’s essentially a double-coil pickup, and the two wire-wrapped magnets are wired together so as to resist producing hum.
However, replacing pickups can cause problems. If you’re playing that Telecaster but replace the single-coils with humbuckers, like this Seymour Duncan SH-6b Humbucker, available through Amazon.com. It provides a high output and maintains clarity. Just keep in mind that you’ll have to figure out how to get them to fit into the spaces where the single-coils were.
If you figure that out and get it all wired up, well, your Telecaster won’t sound much like a Telecaster anymore because that particular guitar sounds like a Tele primarily because of the pickups.
Less iconic guitars will benefit from using humbuckers, though, so it’s not like this is a ridiculous solution that will result in a pyrrhic victory for you and your instrument.
Another possibility for suppressing hum lies in shielding. If you think that sounds fancy and complicated, don’t worry, because it really isn’t. It involves opening up your guitar, which may be something you don’t want to mess with, but rest assured, most guitar players have, at some point, unscrewed everything, moved stuff around, put it together, and still had a working instrument.
Again, most hums come from electricity. It’s powerful and very willful, so sometimes we have to put it in its own little time-out chair. That’s where shielding comes in.
A Faraday cage is a brilliant invention that, at its core, is a hollow conductor. We put the electronics that we want to be isolated from electrical interference inside this conductor, and the electricity that’s causing us problems dissipates on the walls of the cage itself.
But you don’t have to build an actual cage to make this work. You can create a Faraday cage inside your guitar using something like LOVIMAG Copper Foil Tape (available on Amazon). It’s flexible and easy to tear yet holds strong, and it makes such a task incredibly simple.
(It should be noted, however, this is a delicate process, and if tasks like soldering wires back together are beyond you, you should leave it to the professionals.)
Create a DIY Faraday cage with the following steps:
- Remove the strings.
- Take off the pickguard (almost every pickguard is secured with tiny Phillips-head screws, and a small screwdriver should already be a part of your guitar maintenance kit).
- Remove the electric components from inside the guitar.
- Once your guitar is just a piece of wood, layer the copper foil tape in all the cavities in the guitar.
- Cut and trim tape to fit neatly in the recesses.
- Reassemble the guitar’s innards.
- Apply copper foil tape to the underside of the pickguard to create shielding.
- Replace the pickguard and strings.
- Get back to playing, this time with much less (perhaps no) hum.
Noise Gates and Suppressors
Because we live in a technical world, there’s a machine for doing just about anything, and eliminating guitar hum is no exception. One notable option is the Donner Noise Gate Pedal (available on Amazon.com). Using this allows for a complete blocking of all sound below a certain volume level. In other words, you can have all the unchecked buzz and hum in the world, but if it’s below the volume threshold you’ve set, none of it will sound through your amp.
Another option is the Boss NS-2 Noise Suppressor (also on Amazon). It allows you to block specific frequencies so you can selectively suppress sounds you don’t want coming out, like that 50 or 60Hz buzz that occurs when you’re not touching the strings or the jack.
Either solution can be great, but both of them cost more than a roll of copper foil tape. Still, since it’s virtually impossible to completely eliminate all buzzing and humming, one of these may be a better solution for you.
Sources of Problematic Hums
As mentioned earlier, sometimes humming happens, and we have no clue as to why. Sometimes it doesn’t go away when we touch the strings. Sometimes it gets worse. Or maybe touching different parts of your guitar does nothing at all to affect the hum.
But not to fret. Here are some of the most common sources of hums and how to keep them from happening:
The Building You Play In
Unless you have all your gear plugged into the same outlet, you’ll get some electrical interference, especially if the two or more outlets you use have different grounds. This problem is properly known as electromagnetic interference or EMI.
EMI manifests as buzzing and humming, so the electrical wiring of the building in which you’re playing will play a role in producing a buzz. Unless you build your own rehearsal hall and have the electrician wire it the way you want, there’s not much you can do about this. And if you’re playing around town in multiple venues, you can expect to face less-than-ideal wiring situations regularly.
Other Electrical Items
Play electric guitar in your high school jazz band, and you’ll get tons of hum because nearly every band room in America has fluorescent lights. Those are notorious sources of EMI and, consequently, humming and buzzing.
But your microwave, television, refrigerator, and laptop can also be sources of this interference. While you’re on your quest for hum elimination, turn things off and on, listening as you go. You will also notice that some appliances produce more interference than others.
Play your guitar while walking around the room. If it gets louder as you get closer to the kegerator, then dissipates when you move away, there’s your EMI source.
You may be able to remove the offending appliance, or you may not. Do what you can, and depending on the severity of the interference, you may need to look into shielding or noise suppressors, as discussed above.
At rest, the human body produces enough electricity to power a light bulb and can make more as your physical exertion increases. If your cell phone, microwave, or even a fan blowing in your rehearsal room can cause buzz-producing EMI, then so can you.
You are a source of electrical signals (your brain, your heart, you know, the important stuff), so getting close enough to your guitar to play it can send out some electrical signals that will cause interference.
Your Guitar, Amp, or Cables
Aside from EMI, there may be a wiring issue in your guitar or any of the pedals or processors between your guitar and amp, or even in your amp itself. Before you go unscrewing things and randomly trying to troubleshoot, do some investigation, maybe switch some stuff out.
The very first thing you should look at is your cable. Many of us jump around when we play, and even if we don’t, our cables get stepped on. Every player has likely caught his cord on something and had it forcibly jerked out of the guitar jack. Guitar cords take a beating, and they develop shorts easily.
If you plug a different guitar into your rig and the hum is still there, your guitar isn’t the issue. Try a different cable, remove all the effects pedals, and plug into another amp. As mentioned above, the pool of possible electrical problems is nearly bottomless, and the more gear you use, the deeper that pool gets. Switch this for that, then listen for the buzz. If it’s still there, what you switched out wasn’t the problem.
Whatever you do, be methodical about it. Don’t switch three cables at once and try a different guitar, or you’ll never reach the end of the rainbow. It will take some time to do this right, but once you isolate the problem, you’ll better understand how to remedy it.
If you’ve narrowed the problem down to your guitar, it may be as simple (and maddeningly common) as a bad or broken solder joint. If you’re going to be a long-term electric guitar player, invest some time in learning how to run a soldering iron because soldering issues creep up often. If you’ve never dealt with one before, you will, as every electric guitar player deals with it at some point.
One common soldering fault happens at the jack itself. Plugging a cord in and pulling it out over and over puts strain on the jack, and sometimes, the soldering joint cracks or breaks.
If you can produce or eliminate hum by jiggling the cord at the jack (and you know the cord isn’t the problem), then you very likely have a problem with the jack. Open the guitar up and inspect that soldering joint. That may solve all your problems.
If you’ve opened up your guitar and seen that all the solder joints are solid, you may have a grounding problem. Check that all your instrument’s components are properly grounded and that all the connections to the ground are short. Long wires just present more opportunities for EMI.
If you’ve got multiple pickups on your guitar, you very likely have a selector switch that allows you to turn one or more of them off and on. This switch is how we can produce different tones on the same guitar even without a fancy effects bay.
But that switch isn’t indestructible. If you isolated your guitar as the problem, but none of the other possibilities yielded fruit, it could be the selector switch. If the hum goes away when you move the switch to certain positions, there’s a good chance that’s the problem. Changing it out is simple, but as with anything on this list, take your instrument to a professional if you’re not comfortable doing it.
On some level, guitar hum is a fact of life. If you’re playing live or in your rehearsal space, the kind of hum that brought you to this article won’t be much of a problem because you’ll be touching something metal on your guitar very nearly 100 percent of the time you’re playing.
As you search in frustration for the cause of the hum, remember that you’re not alone. My guitar was humming this afternoon, and it’ll hum some more when I play it at my gig tomorrow night. Some hum is a fact of life, but the serious, loud, invasive hums need to be addressed and repaired.