V. Amp/Distortion Tone

• A. Distortion Types/Overview

• B. Pre-EQ'ing

  • i. Frequency Chart

• C. Gain Staging/Layering Distortions

• D. High-Gain Amps

  • i. Park 75

  • ii. Plexi Bright

  • iii. JCM-800

  • iv. Uberschall

  • v. Dual Rectifier

  • vi. Fireball

  • vii. Elektrik

  • viii. Dual Rectifier "Pre"

  • ix. SLO Overdrive

  • x. Doom

  • xi. Epic

• E. Distortion Effects

  • i. Tube Drive

  • ii. Screamer

  • iii. Classic Distortion

  • iv. Overdrive

  • v. Facial Fuzz

  • vi. Line 6 Distortion

  • vii. Line 6 Drive

  • viii. Others

• F. Power Amp DEP's

• G. Dual Amps

• H. "Full" vs. "Pre"

• I. The Elusive Pure Clean Tone

• J. Noise Gates

A. Distortion Types/Overview

The most important part of getting a rock guitar tone is achieving the right distortion that you want. This certainly depends on which amp model you select; however, I want to address how to tweak a amp's tone before describing the available models. For any given amp, dialing in the desired distortion is often nowhere near as simple as turning the "drive" parameter on the amp or amp model up until the sound is as saturated as you like. A typical guitar rig will involve 4 main possible distortion stages - stomp box, pre-amp, power amp, and speaker, and you generally use one as your "main" distortion stage. However, any stage being pushed to breakup will distort in a certain way depending on the nature of the signal sent to it. This section mostly discusses what ways to expect a stage to breakup and how to alter the signal before reaching that stage to get the distortion you want.

The way any distortion stage breaks up is typically the result of the frequency response of the input signal, the waveform of that signal, and the nature of the distortion stage itself. These are tweaked by pre-EQ'ing, gain staging (or effect ordering), and amp/distortion selection, respectively.

As for distortion types, I generally identify 3: fuzz, crunch, and metal, which are derived from the peak frequency range fed into the distortion stage.

Fuzz is generated from distorting bass frequencies and is relatively loose in response to one's playing. Metal is the opposite, created from distorting mids/upper-mids frequencies, and is very tight. It is characterized by the djent sound created during palm mutes. Crunch sits in the middle, being a little boxier-sounding than metal, but not really fuzzy. I find the out-the-box Marshall tone is a perfect example of crunch, while the Treadplate and Fball amps characterize the metal tone.

The output of each distortion stage also depends on the waveform of the signal fed into it. Even if we were to EQ a guitar, banjo, violin, and piano signal to have roughly the same frequency response, the distortion produced by any particular distortion stage would have drastically different tones. For guitar, this is helpful, because we can alter a guitar signal before it hits a distortion stage, by using other distortion effects, modulation effects such as phasers, chorus, or flanger, time-effects such as reverb or delays, filter effects such as synths, and pitch effects such as octavers. This is a lot of ground to cover, so I'm not getting into it here, other than touching upon using multiple layers of distortion.

Unlike the simple pre-EQ distortion types identified above, the results of changing waveforms are more difficult to predict how they will impact the tone. In general, the amp or distortion effect has a relatively similar response given different signals, but you can still hear the impact of whatever effects placed in front of it. In other words, a Marshall will still sound Marshally with a Tube Screamer in front, but you can hear that there's a Tube Screamer in front.

Note that amps tend to "want" to distort one way or another. You can't make a Marshall JCM sound like an Mesa/Boogie Dual Recto just by putting some EQ on the incoming tone. Consider pre-EQ'ing more of a fine-tuning process, even though in some instances you are drastically altering the tone. You want to start by choosing the right amp model. This requires seeing the potential in an amp even if you think it initially sounds like crap. You have to ask yourself questions like, "What if it sounded less muddy?" or "What if I could get the grittiness out the tone?"

I'm not really a fan of fuzz tones, and this guide won't help you dial those in. I prefer to keep the tone being distorted on the bright side. I don't want to dial the bass completely out, though. I like tight bass in my final tone. We want the bass there, and we want the distortion phase to compress it but not distort it. This should keep it well-defined and tight. We use the bass knob (or an EQ effect later in the chain if we're using power amp distortion) to boost the bass to the desired volume, relative to the other frequencies.

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B. Pre-EQ'ing

As mentioned above, one of the main ways to alter a distortion tone is to add some EQ in front of that gain stage, which is commonly referred to as "pre-EQ'ing". Sometimes I refer to this as sculpting my distortion, as I'm carving out the desired frequency response curve.

Using EQ effects to pre-EQ is the most transparent way to do this, preserving a lot of the amp tone while manipulating it to sound like you want. Other methods will have more impact on the signal before it hits the amp, diverging further from its natural tone.

Distortion effects can also be used to EQ the tone. Commonly, this is referred to as a boost or overdrive, using the pedal not to add its own distortion but change how the amp distorts. These terms are misleading - they stem from early use of overdrive pedals when amps had limited distortion available. They boosted the signal level forcing the amps to distort more than they otherwise would. Modern high-gain amps don't need such a boost, but they remain popular because of how they EQ the signal before the amp, changing how it distorts. It's more appropriate to refer to this as using a distortion pedal as a filter, but boost/overdrive commonly amount to the same thing. Using distortion effects for pre-EQ'ing is less transparent, as the distortion effect is usually adding some slight compression and/or distortion of its own, which may or may not be desirable.

For power amp distortion, the power section occurs after the amp's bass/mids/treble/presence controls, so those are going to have more impact on the distortion tone than the final frequency response.

Below is a guide of what to expect when pre-EQ'ing. To take full advantage of this guide, listen to your distortion tone. Does it have too much fuzz or grit? Try reducing the frequencies that correspond to that kind of tone. You don't have to necessarily get the tone to sound totally different, just tweak out the bad and dial up the good.

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