Guitar Gear

I was talking to a sales guy in a shop and got into that age-old debate about overdrive vs. distortion and what they sound like. I’m not a mean person, so before he started flailing wildly, opining on how each sounds and the differences between soft clipping and square-wave distortion, I had to stop him, and just said, “Listen, I get it.”

I guess he felt a need to push his point, and my only reply was a question: “Do you understand that overdrive is a verb and distortion is a noun?” I just let the question hang in the air and waited for the expected response, “What do you mean?” which he finally asked after a bit of a stunned silence. My answer was simply, “Distortion is the end-product of the process of overdriving a device like a pedal or an amp, which is why I call overdrive a verb and distortion a noun.”

That led into a discussion on pedals. I explained that in the end, the goal of all “drive” pedals is to produce a form of distortion as the result of overdriving the input of a device to cause it to clip. The higher the gain, the higher the clipping. And different devices produce different kinds of gain. He nodded in agreement and then I went on to explain the following:

• Boosters overdrive the front-end (preamp) of the amp, causing the preamp to saturate and clip, so what you get is distortion coming entirely from the amp.
• Overdrive pedals have internal soft-clipping sections but also have booster functionality so you get a combination of distortion from both pedal and amp.
• Distortion pedals clip entirely within the pedals themselves, though many provide some gain boost. But typically are used against a high clean-headroom setup because the purpose is to let the pedal produce a consistent distortion sound irrespective of the amp’s volume.

We went on to discuss how each sounds, but I won’t bore you with that. Instead, I’ll break down what we discussed.

Do different types of distortion sound different?

Of course, they do. A pure amp distortion is a distortion produced in the amp itself. That has a sound all its own, and different amps sound differently overdriven. Booster pedals are designed to create amp distortion.

The soft-clipping of an overdrive pedal is considered kind of an “open” and “airy” type of distortion, more gritty than smooth with lots of room for dynamics depending on the instrument’s gain and player attack; that is, the amount of distortion produced varies based on gain and attack.

A hard-clipping device like a distortion pedal produces a more compressed, consistent, low dynamic sound; that is, irrespective of a note being played or its volume, the internal gain of the device is set so high that whatever is played will be amplified into clipping beyond the device’s saturation point. Distortion is not as affected by gain or attack as it is with an overdrive or booster pedal. As an aside, fuzz pedals are ultra-high-gain. These produce that square wave distortion: super-compressed, with lots of sustain (think “American Woman” by the Guess Who).

Circling back to amp distortion, in general, vintage and vintage-style amps distort with soft-clipping as they have few gain stages and in a lot of cases, at least for vintage tube amps, by default, their tubes are biased on the cooler side. Modern, high-gain amps have more gain stages which can produce hard-clipping distortion.

I know I’m covering ground I’ve crossed in the past. But even today, the debate continues, so I think it’s worth it to dust off the discussion now and then.

Here’s a quick reference to help understand how overdrive creates distortion: