Fuzz Pedal

[vvangelovski]

What's specific about the fuzz face (especially the germanium version) is it's ability to clean up with the guitar volume knob and playing dynamics especially on single coil pickups. Yes a full on fuzz sustaining for days can be achieved with an opamp, and there are lots of them on the market. Believe me I've tried to blind test different circuits with 2-3 experienced guitar players, they know the difference, at least they know what they like more. So besides the harmonics content when it comes to fuzz people are either after soaring endless sustain or sensitivity to playing dynamics, or somewhere in between. That's why you have a bazillion fuzz circuits and really they do sound different, at least when you're playing through them.

[old gregg]

The same "fuzz" sound can be easily achieved by simply overdriving a 741, it's simply a matter of driving the thing into saturation giving what is essentially a square wave output

There's still differencies in sounds. I've never liked op-amp distortion whereas I really appreciate fuzz face and fuzz (certainly to do with the internal Op-Amp construction, push pull and crossover distortion and so on). Tube vs transistors is the same thing, it's the way they distort and messed up the sound.

 
about loads, it's just the way it way made in that time. The famous Clapton treble booster works the same. Rise the input impedance (or put a buffer in front of it) and the sound's horribly ear-piercing. Don't know why they didn't use higher input impedance, it seems absurd today, maybe it was a cost thing or it was intentional 

What's more, some guitaristes (Warren Haynes from Gov't mule for instance) accumulate meters and meters of cable to tame high-end on his huge rig. Ok, this is a bit silly, a RC filter will suffice but what your ears like isn't a math equation.

In the same field, a funny thing to do : go to a guitarist forum, start a thread "what's the best buffer I could get" and watch the show