overdrive vs. fuzz

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John Platko
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Post by John Platko »

What is it that makes the "Folk Fuzz" circuit be a fuzz pedal and a "Tube Screamer" circuit
be an overdrive pedal? Or to say the same thing in a bit different way, why isn't the
"Folk Fuzz" an overdrive pedal?

If my question isn't clear I'll try to come up with another way of asking it.

I'm a technical person so feel free to be as technical as you want in an answer.
I've checked through the other topics in this section of the forum and followed
some of the links they mentioned which were helpful but didn't really answer
my question.

Thanks,

John

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FiveseveN
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Post by FiveseveN »

Unfortunately the answer is not at all "technical", not from an electronics standpoint.
The question has been asked and answered many times so I'll give you the gist of it: the difference is subjective but we can identify some general patterns relating to the amount of saturation and sustain, harmonic content and filtering.
There is also a historical definition based on intention (application), not result (sound): an overdrive effect would be used to induce or increase clipping in an amplifier while providing little or no distortion itself. A fuzz would provide a highly saturated signal that is quite distinct from tube amp distortion.
It should be noted that a suficiently flexible architecture could provide a wide enough tonal spectrum to fit within both categories, through manipulation of the gain and other controls and/or input signal level.
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John Platko
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Post by John Platko »

FiveseveN wrote:Unfortunately the answer is not at all "technical", not from an electronics standpoint.
The question has been asked and answered many times so I'll give you the gist of it: the difference is subjective but we can identify some general patterns relating to the amount of saturation and sustain, harmonic content and filtering.
There is also a historical definition based on intention (application), not result (sound): an overdrive effect would be used to induce or increase clipping in an amplifier while providing little or no distortion itself. A fuzz would provide a highly saturated signal that is quite distinct from tube amp distortion.
It should be noted that a suficiently flexible architecture could provide a wide enough tonal spectrum to fit within both categories, through manipulation of the gain and other controls and/or input signal level.
Thanks, that helps explain why I can't seem to get a clear picture of the differences in my head.

Can you give me an example of a vintage overdrive effect that was designed to induce clipping in an amplifier while providing little or no distortion
itself? A tube screamer wouldn't seem to fall into this catagory, or would it?

John

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Post by Nocentelli »

Something like the Electroharmonix LPB-1 (Linear Power Boost) is a single transistor gain stage. It came out originally in the late 60's when pretty much everyone was using tube amps. It generates no clipping within the circuit itself, but can drive a valve amp further into clipping. Plugged into a solidstate amp, it will only make the signal louder, until the headroom of the amp is reached and you might get some rather ugly clipping depending on the type of solidstate circuit. The MXR microamp is another "clean boost" type effect. The Rangemaster (treble boost) is another device like this, but I believe it might actually soft-clip a tiny bit itself at high level settings (anyone confirm this).

There were very few pedals called "overdrive" until the late 70's/early 80's when Boss came out with the OD-1 overdrive, which does produce clipping itself. I believe the whole issue is clouded somewhat by the fact that guitarists tend to play clipping overdrive pedals into clipping valve amps and so it is not clear exactly what is generating that overdriven sound. Oiften, the clipping produced by the pedal itself is not particularly special, but when the pedal-generated clipping (and associated extra harmonics, perceived sustain, comprssion etc) is combined with the extra amp clipping produced by the extra volume from the pedal, it can sound great. Untangling what makes it sound great is difficult. Case in point, SRV famously used tubescreamers (all models, apparently), but he played them into a LOUD tube amp. I believe a large part of his sound was from the amps, the TS just added a little "extra" (level boost, soft clipping, bass roll-off, more harmonically rich) texture to an already great amp sound.
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Post by Nocentelli »

Incidentally, this whole issue of "what is overdrive/distortion?" Is a minor pet peeve/obsession of mine. So much rubbish is spouted online, it's unbelievable. To my mind, they are all non-technical terms that mean the same basic thing: the sound you get out is not what you put in, it is distorted/clipped. Most people have an idea about the sonic differences, I.e. fuzz is fuzzy/woolly/squarewave-ish and not very amp-like, distortion tends to imply smoother than fuzz, more like a high-gain tube amp on full, perhaps. "Overdrive" seems to send people peculiar: I had a lengthy argument online with someone (who said he built pedals, and said he knew what he was talking about): He claimed that you could only ever call it overdrive if it was generated by a tube amp driven into clipping: by this logic, he insisted that boost pedals like the LPB-1 were actually "overdrive" pedals (because they overdrive an amp) but pedals called "Overdrive" were actually a scam perpetrated by manufacturers, and should really be called "overdrive emulators"
It is another frequently repeated nonsense that "overdrive pedals" labelled as such are specifically designed for driving tube amps, and do not create distortion themselves.
Last edited by Nocentelli on 14 Apr 2012, 19:46, edited 1 time in total.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by John Platko »

Nocentelli wrote:Something like the Electroharmonix LPB-1 (Linear Power Boost) is a single transistor gain stage. It came out originally in the late 60's when pretty much everyone was using tube amps. It generates no clipping within the circuit itself, but can drive a valve amp further into clipping. Plugged into a solidstate amp, it will only make the signal louder, until the headroom of the amp is reached and you might get some rather ugly clipping depending on the type of solidstate circuit. The MXR microamp is another "clean boost" type effect. The Rangemaster (treble boost) is another device like this, but I believe it might actually soft-clip a tiny bit itself at high level settings (anyone confirm this).

There were very few pedals called "overdrive" until the late 70's/early 80's when Boss came out with the OD-1 overdrive, which does produce clipping itself. I believe the whole issue is clouded somewhat by the fact that guitarists tend to play clipping overdrive pedals into clipping valve amps and so it is not clear exactly what is generating that overdriven sound. Oiften, the clipping produced by the pedal itself is not particularly special, but when the pedal-generated clipping (and associated extra harmonics, perceived sustain, comprssion etc) is combined with the extra amp clipping produced by the extra volume from the pedal, it can sound great. Untangling what makes it sound great is difficult. Case in point, SRV famously used tubescreamers (all models, apparently), but he played them into a LOUD tube amp. I believe a large part of his sound was from the amps, the TS just added a little "extra" (level boost, soft clipping, bass roll-off, more harmonically rich) texture to an already great amp sound.

Thanks, I think I'm starting to understand.

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Post by mictester »

The differing effects are possibly best described like this:

Overdrive provides soft(er) clipping and often retains much of the original guitar tone. This is usually achieved by putting a couple of diodes in the negative feedback path of an op-amp. Differing types of diodes will give subtle changes in the sound, but the filtering afforded by the selection of component values in the clipping stage and subsequent tone control stages will have much more effect - don't believe the hype!.

Fuzz completely destroys the original guitar sound and turns it into something entirely artificial, usually by brutally clipping the signal into square waves either by "rail bashing" a transistor stage, or clipping across a couple of diodes to ground. Differing types of diodes do make a slight difference, but at stage levels you'll be unlikely to hear that degree of subtlety. Fuzz also can use deliberately misbiased transistors - one of the most interesting fuzz effects is to put a transistor stage just into Class C, and have the incoming signal effectively bias the transistor into conduction - you get pulse-width-modulated square waves (and a lot of other intermodulation effects!) as each note decays.

Various manufacturers try to muddy the waters by mixing up their use of the various terms (they still can't get tremolo and vibrato right).

They're ALL distortion effects, just with differing outcomes!
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