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Vintage threads from the first ten years

Overdrive vs. Distortion

4/21/2003 12:50 AM
Greg P.	Overdrive vs. Distortion This may seem like a dumb question, but here goes: What is the technical difference between an overdrive and distortion stomp box? I am using a variety of tube amps, 72 Marshall 50w, Fender Pro Jr. and 59 Bassman RI and am looking for a stomp box(s) that will respond to the instruments volume control in much the same manner as the amps. Haven't found a stomp box that allows me to clean up my signal via guitar volume control. They all seem to introduce some degree of eq when activated. Seymour Duncan has a pedeal that claims to boost the pickup signal by up to 25db, without 'coloring' the guitars pickup output. If my idea of overdirve is correct, this sounds like an overdrive pedal.

4/21/2003 12:50 AM

Greg P.

Overdrive vs. Distortion

This may seem like a dumb question, but here goes:

What is the technical difference between an overdrive and distortion stomp box?

I am using a variety of tube amps, 72 Marshall 50w, Fender Pro Jr. and 59 Bassman RI and am looking for a stomp box(s) that will respond to the instruments volume control in much the same manner as the amps. Haven't found a stomp box that allows me to clean up my signal via guitar volume control. They all seem to introduce some degree of eq when activated.

Seymour Duncan has a pedeal that claims to boost the pickup signal by up to 25db, without 'coloring' the guitars pickup output. If my idea of overdirve is correct, this sounds like an overdrive pedal.

4/21/2003 2:21 AM
LFOscalator	Overdrive will boost the sound as well as add a slight amount of distortion to simulate a moderately overdriven tube amp. In theory an overdrive should not color the sound in terms of EQ other than slightly distorting it. In practice, some manufacturers do the lack of coloration thing better than others. A distortion pedal simulates an extremely overdriven tube amp that also adds a fair amount of coloration to the sound. For example, they are intended to make a Fender Twin sound like a Marshall. Lot's of coloration involved. LFO

4/21/2003 2:21 AM

LFOscalator

Overdrive will boost the sound as well as add a slight amount of distortion to simulate a moderately overdriven tube amp. In theory an overdrive should not color the sound in terms of EQ other than slightly distorting it. In practice, some manufacturers do the lack of coloration thing better than others.

A distortion pedal simulates an extremely overdriven tube amp that also adds a fair amount of coloration to the sound. For example, they are intended to make a Fender Twin sound like a Marshall. Lot's of coloration involved.

LFO

4/23/2003 1:43 AM
Greg P.	Thanks LFO, Finally, after all these a well articulated description of overdrive and distortion. I was pretty much on the right track, however your ability to explain the differences in laymens terms is greatly appreciated. Greg P.

4/24/2003 7:01 PM
Mark Hammer	Not a dumb question. Been asked 100 times before. 1) Distortion is an outcome; overdrive is a process; fuzz is an objective. So, you get distortion and fuzz by overdriving. If you overdrive in a certain way you get fuzz. What people call "overdrive" is essentially milder distortion that still retains many of the properties of the original signal. In contrast, a "fuzz" tends to have little of the original dynamics of the input, and has a radically shifted-enough change in the balance of fundamental to harmonics that it often doesn't resemble the original very much. What people call a "distortion" is somewhere between those two extremes of "overdrive" and "fuzz". Still, harmonic distortion (i.e., more harmonics coming out than what went in) is a property of everything and anything that gets labelled as overdrive, distortion, or fuzz. 2) In many instances, the type of distortion that people like is actually generated by the amplifier itself. What producesds that distortion is the overdrive created by either setting the preamp gain of the amp high enough, or by feeding the preamp input a signal which is hot enough to "overdrive" it. In the case of a Bassman RI, there is no master volume control so feeding the input with a hotter signal is needed to push it harder and generate the distortion from the preamp/power tubes and output transformer. 3) The extent to which boosting the signal will produce "overdrive" tone is a function of the headroom of the device in question. If I feed a tube or solid-state preamp with a 100mv signal but that stage is built/designed to run clean until the input signal hits about 2v, then I have lots of headroom to boost the signal even further without adding any clipping and additional harmonics because of that. If the booster can provide this gain in a clean manner, then yes it will not end up "colouring" the tone. On the other hand, if I have transistor or op-amp based booster that runs off a 9v battery and I feed it an average 100mv signal, there are some fixed limits as to how much gain/boost I can ask it to provide before it starts to misbehave (and asking it to multiply the input signal by a factor of 50 starts to seriously push the envelope in most instances). That output, in turn, may well be way too hot for the preamp stage it goes to. Similarly, the booster in question may be crystal clear when fed with a lower level signal andprovide 25db or more gain. Feed it with a hot humbucker, though, and any cleanliness that the booster strives for may well disappear. All of this is to say that what seems like it may be a recipe for sweet overdrive tone in one context, may be a recipe for nothing more than a volume boost in another or splat-tone in yet another. Very often, what people like to do is to push a tube amp a little harder with a booster that already introduces some tonal shaping. A good example of this is the Ibanez Tube Screamer. This puts out a slightly hotter output in boost mode (though not as hot as many would like), in tandem with some additional lower order harmonics due to the gentle distortion and tone shaping. As well, because the nature of the clipping introduces some compression, the amp gets hit with a signal that tends to linger a little longer in the zone where you get nice amp overdrive tone. In a sense, the true distortion is coming from the amp, and the overdrive pedal simply gets the signal ready to make the amp deliver its best.

4/24/2003 7:01 PM

Mark Hammer

Not a dumb question. Been asked 100 times before.

1) Distortion is an *outcome*; overdrive is a *process*; fuzz is an *objective*. So, you *get* distortion and fuzz by overdriving. If you overdrive in a certain way you get fuzz. What people call "overdrive" is essentially milder distortion that still retains many of the properties of the original signal. In contrast, a "fuzz" tends to have little of the original dynamics of the input, and has a radically shifted-enough change in the balance of fundamental to harmonics that it often doesn't resemble the original very much. What people call a "distortion" is somewhere between those two extremes of "overdrive" and "fuzz". Still, harmonic distortion (i.e., more harmonics coming out than what went in) is a property of everything and anything that gets labelled as overdrive, distortion, or fuzz.

2) In many instances, the type of distortion that people like is actually generated by the amplifier itself. What producesds that distortion is the overdrive created by either setting the preamp gain of the amp high enough, or by feeding the preamp input a signal which is hot enough to "overdrive" it. In the case of a Bassman RI, there is no master volume control so feeding the input with a hotter signal is needed to push it harder and generate the distortion from the preamp/power tubes and output transformer.

3) The extent to which boosting the signal will produce "overdrive" tone is a function of the headroom of the device in question. If I feed a tube or solid-state preamp with a 100mv signal but that stage is built/designed to run clean until the input signal hits about 2v, then I have lots of headroom to boost the signal even further without adding any clipping and additional harmonics because of that. If the booster can provide this gain in a clean manner, then yes it will not end up "colouring" the tone. On the other hand, if I have transistor or op-amp based booster that runs off a 9v battery and I feed it an average 100mv signal, there are some fixed limits as to how much gain/boost I can ask it to provide before it starts to misbehave (and asking it to multiply the input signal by a factor of 50 starts to seriously push the envelope in most instances). That output, in turn, may well be way too hot for the preamp stage it goes to. Similarly, the booster in question may be crystal clear when fed with a lower level signal andprovide 25db or more gain. Feed it with a hot humbucker, though, and any cleanliness that the booster strives for may well disappear.

All of this is to say that what seems like it may be a recipe for sweet overdrive tone in one context, may be a recipe for nothing more than a volume boost in another or splat-tone in yet another.

Very often, what people like to do is to push a tube amp a little harder with a booster that already introduces some tonal shaping. A good example of this is the Ibanez Tube Screamer. This puts out a slightly hotter output in boost mode (though not as hot as many would like), in tandem with some additional lower order harmonics due to the gentle distortion and tone shaping. As well, because the nature of the clipping introduces some compression, the amp gets hit with a signal that tends to linger a little longer in the zone where you get nice amp overdrive tone. In a sense, the *true* distortion is coming from the amp, and the overdrive pedal simply gets the signal ready to make the amp deliver its best.

4/24/2003 10:33 PM
amz-fx	Overdrive? Fuzz? Distortion? http://www.muzique.com/editor.htm#fuzz regards, Jack

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