it’s a big tangly mess of EMI
This topic can be a complex issue that can send you off on all sorts of tangents. So I thought I would lay down some info here, so someone can read it or ignore it. It can just go into the big pot of opinions on the internet, albeit mine comes with 20 years of experience in electronics & the manufacturing of guitar effects with one of China’s biggest guitar effect brand manufacturers.
I say that not wanting to brag, but by just sharing my opinion on the subject.. I wanted to share some of my rambling tips to help you identify and remove some noise from your guitar rig and guitar effect pedal board. Quite often I get asked why a guitar effect pedal board might be noisy, most commonly when trying to manage someone’s expectations.. It is pretty hard to diagnose a noise by email without being there with you. With everything like this, there is a cause and an effect (no pun intended).
First, there are different kinds of noise you might get on your guitar and you just need to be aware of the kinds of noise your guitar/pedals/amp could suffer from.
Any noise you get is going to be generated from some kind of electromagnetic interference, after all, your guitar/pedals/amp is just an electronic audio circuit. So the more wires and things you throw at it, the more complex this circuit is going to become. Tracing faults can be hard and not necessarily caused by the last component you added to it.
What’s that noise?
So the noise you hear is EMI – electromagnetic interference can arise from many sources, being either man-made or natural. It can also have a variety of characteristics depending on its source and also the nature of the mechanism that produces rise to the interference.
By the very name of interference given to it, EMI is an unwanted signal at the signal receiver and in general there are also some pretty standard methods to identify and reduce the level of the interference.
Different kinds of EMI noise can be :
Radiated – This type of EMI is probably the most obvious. It is the type of EM that is normally experienced when the source and victim are separated by a large distance – typically more than a wavelength. The source radiates a signal which may be wanted or unwanted, and the victim receives it in a way that disrupts its performance.
Conducted – Conducted emissions occur as the name implies when there is a conduction route along which the signals can travel. This may be along power cables or other interconnection cabling. So now we are talking wires, patch cables, power supplies, extension cables, guitar, pedals, amp.. Oh pretty much everything.
Coupled – This occurs when a changing voltage from the source capacitively transfers a charge to the victim circuitry. Bang – that pop when you turn your amp off/on is from a capacitor.
So the main one to look out for are Radiated and Conducted, often interlinked radiated can be conducted through to your guitar amp.
What is your guitar set up?
So first let’s look at your guitar set-up and then talk about the different types of EMI noise found by guitarists and what you can do to help sort it out. You can’t blame one thing, they come as a whole package, a combination, so you need to look at everything. One problem will become amplified by another, you will hear it through your amp.
What Guitar are you using?
Is it a Single Coil or a Humbucker? A bit of a clue in the name of the last one as to what it might do.
60-cycle hum is probably the most used phrase banded about online regarding guitar noises. This is a normal hum that you hear when you turn your amp on.
It can occur and is more noticeable when using single-coil pickups. The single coils hum because their magnetic coils act as an antenna and they are sensitive to external electromagnetic interference from things such as lights, TVs, and even your guitar amplifier. They pick everything up and it gets amplified through pedals, seriously you might even pick up the radio.
It’s called 60-cycle hum, because all the wiring in your home or a venue will generate an electromagnetic field and that will affect your guitar’s signal to some degree. In the USA electricity alternating current cycles at 60Hz and 50Hz in the UK and everywhere else outside of the US.
It is generally why this type of hum is usually called ’60 cycle’ hum and can come from the mains supply, it has a low constant sound. Listen to it here!
60hz Listen https://www.youtube.com/watch?v=bslHKEh7oZk
50hz Listen https://www.youtube.com/watch?v=GqwFimG3X3w
The best fixes for 60/50hz cycle hum would be to shield your pickups and guitar body, even changing the type of strings you use. Get yourself some new guitar cables and patch cables that are shielded. A humbucker will very rarely experience any humming issues and if so, they would probably arise due to a problem with faulty wiring in them.
The reason why a humbucker won’t have humming issues is that a humbucker uses two single coils instead of one. The audio signal that gets amplified from one is out of phase.
Take a look at your power supply, a fully isolated power supply, isolates the mains input from the ac ouput. They also tend to have filters on the outputs to regulate the MA it sends out.
50 cycle hum has nothing to do with pedals, but pedals can amplify it.
Noisy Guitar Amps
You always need to expect something called a “noise floor”, it means some amps are just noisy by design, not a faulty design.
You might hear a hum or hissing sound when you turn an amp on, may be noticeable from increasing the gain/volume. This hum should never really drown out or interfere with your playing, so if the hissing is distracting to you after you start playing, chances are it isn’t just the analogue noise floor of your amp.
Depending on if you are using an old tube amp or a new one. Hiss in tube amps can come from leaky/old capacitors in the preamp, Hum usually comes from aging or failing power filtering capacitors, Bad leads can induce some buzzing. You may face more noise issues with a valve amplifier.
Most preamp valves have a lifespan of between usually 1-3 years, and when they get towards the end of their life they become noisier and more distorted-sounding. This is a common cause of amp noise, and if you’re wondering why your precious tube amp has started producing strange persistent buzzing, this may be the cause.
Solid state amplifiers do not require valves to work, but rely upon a combination of transistors to deliver their sound. They are considered far more reliable than valve amps, and produce a consistent tone as they are less likely to overheat.
Guitar Cables & Patch Cables: Guitar Cables are important and good working cables are very important. If your cables aren’t working well, you might encounter some noisy signals. They need to be shielded and as short as possible, buying some cheap patch cables from different people made out of different materials is not going to conduct your audio very well.
Power cables – the little black bits of wire from your power supply or mains adapter that you put in your pedal can become damaged, all that wiggling needs checking and monitoring, and they all need maintaining. If it’s frayed throw it out don’t tape it up.
Finally, let’s look at your guitar pedals.
Well, pedals do so many different things and you can’t see inside them. They manipulate the sound of everything above and increase volume/gain, but what goes in comes out.
To make these pedals work, you need a decent power supply solution, quality power cables, guitar cables, and patch cables. Oh yeah and pedals!
Analog & Digital Pedals
Guitar Pedals have either digital or analogue circuitry, It’s fine to mix these pedals up, put them in any order, do what you like. BUT ! Put them together on one power supply and they might be drawing different levels of current. The steady supply of ma to a pedal is essential, not too little. It is not just about voltage and polarity.
it is like 5 people sucking from the same drink with a straw, someone will get more.
Quote by Dave Grant
If you are powering pedals on a daisy chain, each pedal is drawing a different ma and the daisy doesn’t regulate between them. Digital pedals tend to draw more current than analogue pedals. Sticking them all on the same piece of wire is just asking for trouble. You need to split the power of these pedals up and make sure you are supplying each pedal with enough juice (ma).
You need to make sure that when you turn one on, the other doesn’t have to compensate power for another. You can use a capacitor filter to help regulate it.
Talking of electronics, that’s what pedals are made of ! Some pedals are made with Germanium diodes and they are used more with high gain distortion & fuzz pedals. The diode is used to help make a lot of noise. If you have one in a pedal, that might be a reason. Some of ours enable you to turn it on or off.
So now you know everything there is to know, here is my ultimate top tips for fixing noisy guitar effect pedals.
Guitar Power Supplies – Start with using a quality filtered power supply that isolates & regulates the mains power for each pedal. It needs enough ma to meet the draw of the pedal. Do not underpower your pedal.
Power supplies with isolated outputs have capacitors that act as filters on them (like an old amp) they maintain a constant ma output, they maintain a regulated supply and they are made especially for guitar pedals. A power supply you use on your pedal or audio equipment is not the same as a universal power supply you find in a kitchen drawer. If you find a power supply in a drawer leave it there.
Isolated power supplies isolated the mains from the pedals. They stop the alternating current by using a transformer for the input and capacitors on the output.
A noise filter – We have the JOYO ZGP it’s a capacitor that will regulate the ac draw for your pedal, you can use it on your daisy chain wherever you want, on an analogue pedal, on a digital pedal where the draw of that pedal may not always be constant. The JOYO ZGP cleans up the signal from a power supply that may not be providing enough juice.
Guitar & patch cables – Use as short of a guitar cable as you can. They also need replacing like you might service your car/bike/lawn mower. Don’t spend on pedals and scrimp on cables, that does not make sense.
Don’t use patch cables from different suppliers, make them out of the same materials and make sure they are shielded you can even make them yourself so you know what they are capable of and that they are of the same length/quality.
The ultimate noisy guitar effect pedalboard Checklist
When you’re having noise problems and you don’t know what part of your rig is causing it, the best way to narrow it down is to check all the components not blame the newest addition..
I tend to do it in this order just to eliminate the cause:
- Try and identify what noise you have. If it’s a low level hum, just move house haha.
- What pedal is it? Assume a noise floor with your pedal, just as you would with an amp. if it’s a high gain/germanium fuzz consider using a noise gate pedal to mute any noise you hear when you are not playing. It won’t cure it, but it might help reduce it during the silent parts. Is it noisy when it is on/off/both?
- Plug your guitar directly into your amp. If you’re still getting noise, it’s most likely from the guitar, amp, or the single cable you’re using to connect the two and not your pedalboard. If you have single coils, try another guitar.
- Check your cables. Use a cable tester or just keep plugging cables into a working amp and running signal through them. Just get new ones if you can, don’t scrimp on them, cheap is cheap. Also, move the cables around especially the ends near the jacks to see if there are any loose connections, pops and crackles. Don’t cross them over other cables, especially power cables. Guess what you move about, they wear out!
- Check your power supply output ma. Make sure you’re using the correct power supply for everything and that the mAs match. Do not exceed the output ma, daisy chains will cause more noise and using a filtered power brick will fix the noise problem.
Isolated power supplies have isolated outputs too you know, so they do tend to isolate the input and the output.
Disconnect everything and plug in all pedals separately, powering them up one at a time, after you have Just what it sounds like, run every pedal in your chain individually to figure out if you can figure out where the problem is.
Anyway, maybe a load of waffle, but it might help if you managed to read all of this.