Rock music is one of those genres which benefits a lot from a good distorted tone, whether it’s rhythm guitar riffs or in-your-face all out soloing, cleans are just not strong enough for this style. That being said though, not just any distortion will do; it has to be appropriate to the overall sound of the music you want to play, and above all else compliment your playing rather than detract from it. Luckily, there are a lot of ways in which you can get distorted tones with the electric guitar, so practically any heavy sound you can imagine is available to you. There are literally tons of different and interesting distortion pedals on the market, and while it would be impossible to consider the relative pros and cons of each one in a simple blog, it is possible to compare them collectively with another common way of achieving a distorted tone: the tube amplifier.
With tube amps, the distortion tone comes from pushing the tubes past a certain threshold, so that they break up naturally and distort the guitar signal; this is commonly referred to as overdrive, but when taken to an extreme it is possible to create a stronger effect more akin to distortion. Effects pedals tend to achieve distorted sounds in different ways. While an overdrive pedal will work with the amplifier itself to boost the signal and overdrive the tubes, many modern distortions work in a more independent way.
The difference between amplifier overdrive and effects pedal distortion is great, and to hear it in action, all you have to do is compare the sounds of a couple of different bands. Angus Young of ACDC is perhaps one of the most famous technophobes in the history of rock; with a pedal collection close to zero, he relies almost exclusively on overdriving his amplifier to get that famous edgy classic rock tone. On the other end of the scale would be something like the gear rig of a player like Pink Floyd’s David Gilmour, which consists of a number of different distortions and modulation which are carefuly balanced with the amplifier to produce a more sophisticated kind of distortion. The difference in tone between these two players is huge, as are their demands for amplifiers.
Headroom again comes into play, as if you decide to go the effects pedal route, you need an amplifier capable of giving high volume crystal clear cleans, so that the tone from the distortion pedal is not mixed with overdrive from the amplifier. If you prefer overdriven amplifier distortion and want to keep your ears intact, then you will need less headroom, so that you can reach that broken down tone at more acceptable volumes. The main difference between amplifier and effects pedal distortion is that one of them sounds much warmer than the other. With a good tube amp head, the distortion can be very rich and, above all, natural sounding. A distortion pedal can sound a little more cold, metallic and dark unless it is made with good components and set up well in your rig.
The two kinds of distortion are very different, and it is often a matter of personal preference when it comes down to choosing which is more appropriate for a particular track. The two can even be mixed together to create even more interesting textures. As usual, experimentation is the key, although if you are the kind of person who wants a lot of variety in overdrive and distortion, then it is usually a lot cheaper to buy different effects pedals than to buy different amp heads!