Distortion is what defines many genres of modern music. From the iconic fuzz sounds popularized by Jimi Hendrix to the face-melting, high-gain tones employed by bands like Metallica and Slayer – distortion is everywhere. Having good command of the different types of distortion available to you can make you an extremely versatile guitarist.
So what is distortion? Why does it occur? Do tube and solid-state amps distort differently? Why would you need distortion pedals? We’ll answer these questions and more below.
Your guitar produces a relatively weak electrical signal that looks a lot like the dashed green wave in the image above. In order to create a signal that can be played by a speaker and heard by everyone, it needs to be amplified. Your amplifier takes this signal and increases the amplitude of the sound wave, which increases its volume. Once the signal is processed by the amp and reaches the speaker, it looks more like the solid blue wave. Notice that it’s similar to the dashed green wave, but the peaks and valleys of the signal are higher and lower, respectively.
At low volumes and gain, the sound that comes out of the speaker is ‘clean’ – without distortion. Now, imagine you turn the volume knob on your amplifier higher and higher. If the signal stays within the amp’s clean headroom, represented by the horizontal yellow lines, the signal stays clean. Eventually, there comes a point where the components inside the amplifier cannot handle the signal’s increasing amplitude. This is demonstrated by the red wave in the graph above. The components of the amplifier have no choice but to ‘clip’ the parts of the signal they cannot handle. The clipping of the signal wave is what causes distortion.
The more severely clipped a wave is, the more it’s distorted. Distortion comes in different levels, usually categorized as such (from less to more severe): overdrive, distortion, and fuzz. Yes, distortion is both a general and specific term in this case. You’ll need to infer which your fellow guitarists are using by context.
When just the tip of the wave is clipped, ‘soft clipping’ occurs, known to us guitarists as ‘overdrive’. In this case, the amp has been pushed just past its limits and the signal is being clipped, but only a bit. This creates a pleasing distortion perfect for blues and classic rock. The intro of Stevie Ray Vaughan’s Pride and Joy is a classic example of bluesy overdrive.
On the other hand, when a signal wave is clipped so harshly that it looks completely squared off, then you get ‘fuzz’. Fuzz is a brutal, severe type of distortion that is tough to tame and creates a rough, grating tone that’s perfect for generating tons of noise. Generally, an amp won’t be able to create completely squared off waves like this unless you really take it to its limits. Rather than abuse their amps like this, most guitarists get their fuzz tones from pedals. Fuzz pedals contain specially designed circuits for creating harsh square waves. Foxy Lady by Jimi Hendrix is the textbook definition of fuzz.
Somewhere in the middle lives ‘distortion’ – the kind known by rockers and metalheads. It’s also called ‘hard-clipping’, where more of the wave is clipped than in soft-clipping/overdrive, but not so much that your signal turns to fuzz. Metallica’s Master of Puppets is a great example distortion.
Tubes vs Solid State
In a tube amplifier, signal clipping is more gradual and less harsh than the clipping that occurs in a solid-state amplifier. A solid-state amp tends to clip waves earlier and more suddenly, and that’s why, generally speaking, tube amp distortion sounds more natural and pleasing to the ear. While amp modeling can alleviate this to a certain degree, many professional guitarists still swear by tube amplifiers. If you’re curious about the physics behind tube and solid-state distortion, TrueAudio.com has a more in-depth article. It doesn’t have to be all or nothing, however. The Vox VT20X hybrid amp, for example, uses both tube and solid-state technology to get the best of both worlds.
Volume, Gain, and Pedals
You can think of overdrive, distortion, and fuzz as different types of distortion, each having their own uses for specific genres of music. However, things are a bit more nuanced than just the type of distortion. A guitar amplifier amplifies your signal in two stages: preamp and power amp. Because the purpose of these two amp sections is to amplify, that means they also distort your guitar’s signal. However, they do so in different ways and for different purposes. It’s good to be mindful of how the preamp and power amp sections affect the nuances of your distortion. We all know the Gain knob adds distortion to your sound, but did you know that the Volume knob also adds distortion?
The Gain knob of your amplifier controls preamp distortion. Preamp distortion has a smooth, compressed character to it. If you only use the gain knob to add more distortion, your tone can sound thin.
Power amp distortion, on the other hand, is more punchy and dynamic. The higher you set your amp’s volume, the more power amp distortion you introduce into your sound. In our Become an Amp Expert guide, we talk more about the difference between these two sections of your amplifier.
Dialing in the right type and amount of distortion can be tough. While playing on stage, you’ll probably have the volume set pretty high, so you get plenty of power amp distortion. However, when you practice at home, you’ll need to lower the volume considerably. Sadly, low volume means little to no power amp distortion. This is just one of the many possible instances where getting a consistent tone is difficult. Thankfully, effects pedals can make dialing in the right type of distortion as easy as tapping your foot.
Effects pedals can take the guesswork out of getting the right amount and flavor of distortion. Instead of fiddling with the volume knobs and the gain knob on your amp, you can buy a fuzz pedal that will instantly make your rig sound like a doom metal machine. These pedals contain circuits that clip your signal much the same way a guitar amplifier would. Every pedal model is unique and affects your sound differently.
Running your guitar signal through an effects pedal means your tone takes on the characteristics of that pedal. The Big Muff Pi instantly transports your tone to early 90s Seattle grunge. The Ibanez TubeScreamer gives your mids a boost and pushes your amp further into overdrive for some Stevie Ray Vaughan bluesy tones. A specific overdrive, distortion, or fuzz pedal can immediately turn your rig into a completely different beast. There are even distortion pedals you can buy that mimic the sound and breakup of iconic amplifiers, like the EVH 5150.
A Clean Canvas
Some guitarists prefer to get all of their gain sounds from pedals instead of from the amp itself. While it’s possible to get overdrive, distortion, and fuzz from some amps, you might find that your amp doesn’t have a whole lot of gain on tap. An amp designed specifically for blues might not be able to get into hard rock or heavy metal territory without some help. An overdrive pedal can help push this type of amp further into distortion. A distortion pedal can transform it completely into a rock machine. Unless you have a really high-gain amplifier, forget about getting fuzz tones. However, just by spending a measly $30 bucks on a fuzz pedal from Donner, you can step into the world of Jimi Hendrix.
You can always use your amp’s clean setting as a canvas for distortion pedals. However, don’t let this fool you into thinking that you don’t need a good quality amp! Even the greatest effects pedals can sound terrible through a crappy amp. Pedals aren’t for fixing the quality of your sound, but for enhancing it. You can even combine overdrive, fuzz, and distortion pedals with your amp’s high-gain channel to create some interesting tones!
On the opposite side of the spectrum, some guitarists prefer to get all their gain tones from the amp itself. However, because not all amps excel at high-gain music, you’ll need some foresight when purchasing your amp if you choose this route. Some amps, like the Peavey 6505, are made to excel at high-gain music.
Thankfully, effects pedals can turn even the most polite amp into a snarling beast. However, be aware that certain amps can be temperamental, so be sure to do some research before buying an amp. Usually, guitarists will mention if an amp ‘takes’ pedals well. This generally means that the clean channel of the amp will work well with distortion pedals. If you haven’t already, check out our guide on how to buy an amplifier for some more things to watch out for.
A few guitarists look down on distortion pedals, accusing them of sounding thin or cheapening your sound. Don’t listen to them! As long as you enjoy the sound, use whatever gear you like!
To pedal or not to pedal?
Do you need pedals? No. Some guitarists enjoy them because they love tinkering around with their sound. Some like the control they get from having specific pedals with specific sounds they can turn on and off or combine at will. With dozens of brands and thousands of pedals to choose from, each with their own characteristics, pedals can really help shape your sound. It’s up to you to experiment.
Do you like the sound of your amp with the volume cranked up to 11, but can’t run it like that at home? Maybe the Earthquaker Devices Acapulco Gold would be a star on your pedalboard, allowing you to get iconic, punchy power amp distortion without having to turn the volume up crazy high. Maybe you need more gain than your amp has on tap, so a distortion pedal like the Boss DS-1 might give you the high-gain tone you’re looking for without having to buy a new amp. Pedals can really give you a lot of versatility and freedom to adjust your tone. Soon, we’ll publish our Pedals guide to help you find the right effects to find the sound you’re looking for.
Distortion is a very broad topic. We’ve covered a lot here. Now you know what’s happening when you turn your volume or gain knob up and what the different types of distortion pedals do. Now it’s up to you to experiment. Try out different gain and volume settings on your amp. Find a couple of overdrive or distortion pedals and see how you like the sound. It’s up to you to experiment!