Dealing with noise (part 1)

Noise is every guitarists’ worst enemy. We’ve all experienced hissing, buzz, crackle and hum. It’s frustrating but there are many things you can do to reduce noise to a minimum. In this first of two articles we’ll look at the basics, the reasons for noise and how to solve the problem.

I often get asked ”why is David’s guitar dead quiet while mine is hissing like hell?” David’s guitar is certainly not as silent as it may appear. If you’ve ever listened to a bootleg or had the chance to see him live, you’d noticed that his rig is far from silent. However, he might be dealing with other issues than you. Let’s start with some basics.

Noise is mainly caused by two things – outside interference and noisy components (usually a combination of both). Outside interference is electrical radiation being picked up by almost any component in your rig mostly due to lack of proper ground and/or shielding. Noise caused by the components them selves is often as a result of cheap or faulty parts, bad assembly etc.

Quick guide:
- Make sure your guitar and amp is connected to ground that has a clear path out of your house in into ground.
- Check every cable (instrument, patch and speaker) for bad connections and plugs.
- Make sure that no instrument or patch cable is touching any power cables.
- Check every power supply for bad connections and make sure they’re not overloaded.
- Switch off any nearby computers and assigned electrical components, radios and stereo units, cell phones and efflorescent lights.
- If possible, make sure that your amp and pedal board runs on a separate power circuit than your TV, computer, refrigerator, light rig etc.
- Be tough on your pedal board and ditch any overly noisy pedal.

Ground is what the name implies – a connection to the earth. In case of a power failure or short circuit, the ground connection will lead the electricity out of your rig, through the wall and outside into the ground, rather than the electricity going through your body, which is a substantial conductor. We’ve all heard stories about musicians being fried or shocked on stage, and although this may sound cool, it can be very serious so the ground connecting is there to avoid this.

You’ve probably experienced hearing this loud buzzing from your guitar and if you touch any of its metal parts, the buzz will change in volume and/or pitch. This indicates that there’s a bad ground connection somewhere that needs to be fixed. Unscrew the pickguard, check all ground cables and make sure they’re connected to the right parts. If the buzz is still there you need to check the power outlets to your amp and pedal board.

US power cable plugs has three pins and the lower round one is ground. Some musicians cut this one off, because the plug won’t fit into all outlets but this means you’ve cut the ground, which is like asking for trouble. As a touring musician you should always carry a converter plug (with ground) that fits into any outlet. Most European plugs have two pins with ground in the plug it self (usually two metal strips) but in any case, make sure that all extension cables have ground! The best way to check this is to always keep a circuit tester ($20 at hardware stores) in your utility kit. Plug it into the socket and check the ground connection.

The word shielding is a bit misleading and often misunderstood. It does not mean that you’re shielding your guitar from an outside source with a protective layer but a shield (like copper foil) will gather the outside electrical interference that’s causing the noise and drain it out of your guitar. For this to work, you need to make sure the shielding is connected to ground (a cable that’s either connected directly to the output jack or via a tone pot that’s again connected to the output jack) or else it will have no place to drain the noise and it won’t have any effect. In some cases your noise problems will be eliminated with a proper shielding but it will only help for some types of interference (certain frequencies) and it’s by no means a miracle cure.

60 cycle hum
60 cycle hum (or 60hz) is a loud, low frequency buzz coming from your guitar. Bad ground connection is consistent but 60 cycle hum is directional and if you walk around the room it will come and go depending on the radiation field. This kind of noise is caused by outside electrical interference and it may come from a nearby transformer, light rig, your kitchen or just about anything. Now, shielding your guitar won’t eliminate this kind of noise because it’s picked up by the pickups. Vintage style single coil pickups have magnetic poles that are exposed to any outside interference so they’re basically acting like antennas. In case you experience 60 cycle hum, you need to locate the source and switch it off if that’s possible (computers, lights, TVs, refrigerators etc) or, in case you’re on a stage (interference from ligh rigs, power sources, PA systems etc) try to find a separate power circuit.

Humbuckers and so-called “noiseless single coils” are less subjected to this kind of noise, or noise in general. Humbuckers aren’t ideal for recreating David’s tones and those of us that swear by our vintage style single coils may find it easier to live with a compromise but it’s well worth checking out EMG, Lace Sensor, Fender Noiseless, Kinman, Barden etc. Most guitarists will agree that these does not sound like vintage style single coils like Fender CS69, Duncan SSL5 etc, they lack some of that bite, the crisp top and character, but that’s ultimately down to taste.

Guitars and pickups
As we’ve talked about, a proper ground connection and shielding is vital for keeping your guitar as silent. I’ve had great success with shielding the pickup cavity of my guitars with copper foil but then again, I’m lucky to rarely encounter 60 cycle hum or bad ground connections. Again, vintage style single coil pickups is a compromise no matter what and you are bound to have some level of noise because the pickups will pickup electrical interference in addition to your strings.

From time to time you may also experience a pickup that’s microphonic. This is easy to detect as one or more of the pickups will be feeding uncontrollably and insanely loud (not to be confused with natural feedback). This means that some of the parts inside the pickup are loose and you need to pot it – reassemble the pickup and dip it in wax to keep all the parts in place. This is a complex operation so in most cases you’re better off buying a new pickup (or returning your guitar if it’s brand new).

Amps are no different from any other component in your rig but slightly more difficult to deal with and in case you’re not trained in electronics I strongly advice you to take your amp to a trained technician. Replacing a tube is easy but if you start to poke around you might end up with a serious electrical shock… worst-case death.

Assuming that your amp is properly grounded, the most common reason for noise is bad tubes, loose parts or parts that needs to be replaced. Check both the head and cab for loose construction and cracks in the wood, loose screws, dying tubes, wires etc. Old transformers and leaking/dry caps will add noise but also cause irregular current in the amp, which is not good for neither the tone nor the components, so make sure you take your amp to a tech and have this checked once in a while.

In case of microphonic tubes you might hear a vague hollow ringing coming from your amp. This is typical for a tube that’s been shaken up a bit from vibrations in the chassis and it’s time to replace the tube. If you’re unsure you can use a wooded stick (remember that metal is a conductor and should never be used!) and tap gently on the tube. If it sounds like you’re picking a rubber band it means that the tube is broken.

Again, assuming that the ground is OK and your guitar and amp is working properly with the needed shielding, it’s time to look at the signal line.

Cables acts as long antennas picking up electrical radiation, radio waves etc within a fairly vast range. Cheap instrument and patch cables are not shielded (or not shielded properly) and as you now have learned, there’s nothing to drain the interference that’s causing the noise out of the signal path. So the moral is – get good quality shielded cables!

Length is also a factor. No matter how good the cable is, the longer it is the more it will drain your signal. A 20ft instrument cable should be more than enough for most setups. I swear by my Evidence Audio Melody cables (David’s choice since 2005). I also recommend Lava, Planet Waves, George L’s, ProCo and Mogami.

Patch cables are often overlooked and one tends to use whatever’s convenient. Those multi packs with different coloured cables are strictly forbidden! Make sure all your pedals are connected to good quality patch cables that are cut as short as possible. You want to connect the pedals not clutter your board. Again, length is crucial and although your board might include only the average of 10-12 pedals, small cables can turn up to be pretty long if you add them up. George L’s, Lava Mini and Evidence Audio Monorails are ideal for boards that are frequently rearranged.

Speaker cables are perhaps even more overlooked than patch cables. Hands in the air those of you who’s never used an instrument cable between the head and speaker cab… Instrument cables are not designed for this and in worst case you might overload the cable and short-circuit the amp. Be sure to use dedicated speaker cables that are designed for more power. I strongly recommend the Evidence Audio Siren for this.

I don’t mean that you have to spend all your savings on expensive cables but keep in mind that although it’s no fun getting a cable over a pedal, it often pays off putting a little extra into it. The reason why your new pedal may sound like shit might be the cables that are attached to it. Check out this Q&A with Tony Farinella from Evidence Audio for more about the importance of good cables.

Power supplies
Feeding the right power to your pedals is crucial for eliminating noise. The wrong voltage or the wrong use of power supplies can be the main source of your frustration. A pedal board with 10-12 pedals is often hooked up to 1-2 Boss 9V adapters with most the pedals in a chain. One pedal might need a separate 18V adapter and perhaps 1-2 vintage pedals are running on battery. Batteries are noisy by nature but that’s a compromise most of us are willing to take to get that old fuzz pedal warm and smooth. Some pedals like digital delay processors are often a bit more demanding than the average overdrive and might start to distort and hiss if you place them in a power chain with other pedals. The more adaptors you keep the more they require your attention and you shouldn’t take the risk of one of them not working in the middle of a show.

The best way to power your pedals is to use one unit dedicated to power as many pedals as possible. Voodoo Lab, Cioks and T-Rex (among others) offer power supplies in all shapes and variations depending on how big your pedal board is. Each unit has separate lines for each pedal for a more consistent signal. Some of the bigger models also allow different voltages so that you can use all your pedals on one unit.

Don’t forget the power cable to your amp! Older amps often have chords that looks like a curled up snake or worse. These should be replaced immediately. Not only for noise issues but you don’t want to get an electrical shock sent through your body next time you’re unplugging your amp. A good quality power cable ensures the correct current to your amp, which again means less noise and less wear on the parts. Check out the Source from Evidence Audio or simply take your amp to a skilled technician and have him replace the old cable with a new.

It’s impossible to cover everything but I hope this answered some of your questions. Please feel free to use the comment field and share your tips and experience! Next time we’ll look at pedal boards and how to tweak your favourite tone without frustrating noise problems.

10 comments so far

  1. Larry Davis says:

    Do I understand you are saying that a 20 foot cable is better for less noise than a 10 foot?

    [The shorter the cable the better. - Bjorn]

  2. Neil Yoder says:

    The stock neck pickup on my Mexican Telecaster buzzes like crazy whenever certain stage lights are in use. Can this be avoided, or do I simply need to find a different circuit for my amp?

    [As I'm sure you are aware, vintage style passive single coils are noisy by nature as they're pretty much acting like exposed antennas picking up all kinds of interferance. Stage lights will often be a problem and Telecasters are often noisier than Strats and other guitars. It's probably nothing wrong with the guitar or that particular model. Try to eliminate as many sources as possible and one of the upgrades you can perform is replacing the stock pickups with someone with a better shielding. Learning how to use a volume pedal and the guitar volume as well as how turn away from the source is crucial for eliminating as much noise as possible :) - Bjorn]

  3. Keith says:

    I can tell you from experience that using a circuit tester,( the type with 3 leds, that tell you when you have proper polarity,and ground.). In the US, a small Greenlee tester is about $8.00, and I use one every time I plug into a new place, and this is why. In the late ’80s, I played a club with no grounds on the PA, or my amp. I found this out when during soundcheck, I was strumming some chords, and went to the mic to speak to the soundman. Next thing I knew, I was lying on the floor, about 5 feet from the mic stand! Most have experienced the very uncomfortable feeling of mic shock, but someone had somehow routed a neutral in a way that when I touched the mic with my lips, while holding my axe, I got a full 120v through my lips. This could have been deadly, and now I carry a little green tester to even jams, and check for proper line, neutral, and ground, by simply pluging the two inch tester in, and seeing that the correct lights are indeed on. It will save your sound, and gear, and possibly your life. And never play
    Peace, Keith

  4. kelly says:

    my telecaster makes a scratching sound when its plugged in, is this a shielding or ground problem? I shielded my other telecaster and I also took off the chrome cover for the neck pickup and it sounded like my strait.. but, then it bugged me..because I already had that sound with my strait…thank you..and hope to hear from you, kelly

    [What do you mean by "scratching sound"? - Bjorn]

  5. James says:

    I’ve been hearing this clicking sound that happens maybe every second at a constant rate when I have an instrument cable plugged into either my amp or directly into my mixing console (which is connected to my computer via firewire). It happens both with a guitar plugged in and unplugged and the cable just hanging from the input of the amp. I can’t figure it out. It’s the same for all my cables, new or old. I’ve tried plugging into different electrical outlets, and even an extension cords 20 feet from my house and still hearing the clicking sound. The only times I don’t hear it is if I try it at a different house. What could be causing this problem?

    [Well, it's definitely not your guitar than, since the noice appears even when it's unplugged. Have you tried different cables? Are always near your computer? Sounds like there's some static electrical interferance that might be coming from your computer or nearby electrical components like your fridge, TV, lights etc. Could also be a transformer outside your house that's radiating. Try to sort out what's different when you're at your friend's and tro to eliminate those sources when you're at home. If it is static buzz, then you might want to consider better shielded cables and perhaps even shield your guitar. One way to tell is to try a humbucker guitar. - Bjorn]

  6. Mark says:

    Good article and information, I don’t think ever thought about the difference between speaker and instrument cables.

    I am curious if James found out the cause of the clicking sound he was getting. I had the same thing happen to me when I plugged direct to the PA last weekend with a Joyo American pedal (Fender amp sim). Just the pedal alone plugged into the PA got a clicking/tapping sound that suddenly appeared after playing a whole set. At home though it sounds fine. So I am guessing something at the board was going on.

  7. JCA22h says:

    Having the same problem as James…And i mean EXACTLY. Mines a Jet City JCA22H.

  8. Silvio De Santis says:

    I had a disturbing click (frequency of 1 hz) coming out of my amp for about a month. I swapped guitars, cables, amps, it was still there. It drove me crazy as I had a $1000 Warmouth Strat (and a Fender Classic Player 60s strat) and 2 Hiwatt DR504 (one from 1979 and one from 1981). I finally figured out it came from a clip-on watch I had attached to my belt !
    I do not know if humbuckers would have made this click.

  9. connor putrefy says:

    Just stumbled upon this site and found it very intriguing indeed. Perhaps some of you may be able to help me. I own a Diezel Einstein amp which is absolute marvel in audio amplification but where we practice i get this strange noise from it when i touch the gain dial. It doesnt happen all the time. But the noise is like a crackling at first i thought it was a dodgy pot but i had the amp inspected by my local amp tech who ran the amp all day and couldnt hear a single crackle. He checked the amp and said there was nothing wrong with the amp whatsoever, the polar opposite in fact. The place where we practice is has strip flourecent lighting, could this be a factor? why just the gain knob? i must point out that the knobs on the amp are allen key adjustable, so thats an additional metal part though i didnt think that would be an issue? Like i say the crackling doesnt happen all the time. I wrote to diezel and they said replace the tubes but my tech said that would be silly as he said there is nothing wrong with tubes whatsoever. would a dodgy 4 gang plug cause this sort of almost earthing sound. Oh , he tested the earth of the amp too and it was fine, quite pickling indeed. any thoughts?
    all help appreciated
    many thanks

    [Hard to tell. Doesn't seem like a tube-problem. Noise can be hard to detect and it's often the strangest things that cause it. I have to pass on this one… anyone? - Bjorn]

  10. Phil Hendren says:

    Hello , great article but i need some clarity…please.. I just shielded my bass guitar and i does not sound any different. You said you have to ground the shielding to the out put jack right??? If the volume pot is contacting the shielding with a brass lock washer is it still needed ? Should i try it just to be sure? MY bass is a Dean Edge Q5 with EMG HZ pickups from the factory…

    [Seems like you've done it right but take the guitar to a tech if you're not sure. Shielding won't eliminate noise but it will reduce it dramatically. If there's no change, then you've either done it wrong or, the noise is caused by so-called 60 cycle hum, which can't be eliminated with shielding. Only by eliminating the source or simply turning away from it. - Bjorn]

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