I. Frequency Chart

Here is a guide to how the tone is likely to sound with various peak frequency ranges hitting a saturated gain stage, or some frequency range being absent/deficient. Note: this is not foolproof - it depends on the amp/gain stage. Also, the numbers aren't an exact science - consider them to be fuzzy and use as a guideline only.

Also, please note that just because some frequency range is the peak doesn't mean it will dominate the tone. It is possible to have a mostly flat frequency signal with a slight peak in the muddy range, yet the signal won't be total mud - you'll get a bit of all the characteristics listed below. You can mix and match and balance certain aspects of the distortion with other ones. Usually that's exactly what you want to do. IE, a wide boost at 700 HZ will often add the djentyness and creaminess from the frequencies around it, rather than simply making the tone flat.

Make all these links to audio.

Freq (HZ)	Peak	Lacking
0-150	Muddy	Thin
150-250	Fuzzy	Thin
250-500	Creamy	Cold
500-800	Flat*	Tinny
800-1500	Djenty	Buzzy
1500-3000	Crispy	Sterile
3000+	Gritty	Smooth

* Flat means there is no real distortion tone - it sounds like compressed mids.

Applying this logic to the fuzz/crunch/metal distortion types I mentioned above, fuzz tones obviously emphasize low-end and metal tones upper mids. Crunch tones tend to emphasize mids, but extend into both metal and fuzz territory - the result of mixing both of them together more-or-less.

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C. Gain Staging/Layering Distortions

As mentioned above, one of the main ways to alter a distortion tone is to place effects in front of that gain stage, that change the waveform of the incoming signal.

This is a very wide-open topic, but the general rule is to expect the final tone to be a mix of both. In other words, putting a phaser in front of a distorted amp will sound like phaser + the distorted amp tone. But it's obviously different than placing the phaser behind the amp. The way I differentiate between these is I think of anything placed before a distortion as "going into" that distortion, whereas anything placed after a distortion "goes on top of" the tone.

The main topic I wanted to discuss here was how to tweak having multiple distortions in the same signal chain, which is usually the case, even if only one of them is generating most of the distortion. My recommendation is to use one distortion stage as your main stage, with the others trying to complement it. That being said, zero'ing out the others usually gives me bad results.

Take a typical distortion effect -> preamp -> power amp chain, where each is contributing some distortion. I'll often use my pre-amp as my main distortion stage. While I am mostly using the distortion effect for pre-EQ, I may also want it to deliver a touch of compression and/or distortion. Depending on the distortion effect and amp, this slight distortion may warm up and smooth out the downstream amp distortion, or it may make it edgier and more aggressive-sounding.

As another example, let's say given the same chain I want the distortion effect to provide most of my distortion. Setting the amp's preamp Drive to 0% is going to sound weird. For a Marshall amp, I find I have to get it to at least 10% for the tone to start sounding natural, and about 20% to add the Marshall flavor. If this means the Marshall is also adding a little distortion, so be it. If I end up with too much distortion, I'll back off the distortion effect's Drive. Sometimes you also want to back off the distortion effect's output level, and dial in more pre-amp Drive from the amp or vice versa. This can have differing tonal effects even though you are getting the same total amount of distortion.

The same ideas apply for pre-amp vs. power amp distortion. Even if only one is your main distortion, you still want to give a little juice to the other.

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