Right now I am using a MXR classic distortion pedal, and whenever I attempt to get a a good distorted tone, it sounds muddy.
I was thinking about getting a big muff, but I want a very versatile distortion pedal, which can do some very slight dirt, to very high gain dirt without getting muddy.

Any suggestions?
Gibson Les Paul Traditional
Crate V33 212 Combo
DigiTech Whammy IV
Dunlop Crybaby
MXR Classic Distortion
Ibanez DE-7 Delay
Boss GE-7 Equalizer

The big muff wouldn't be to bad.
i think an OD might be what you need, though, something like a TS9
Get an OD pedal, not a distortion pedal.

Digitech Bad Monkey
Ibanez TS808/TS9
Maxon OD808
BBE Boosta Grande
Fulltone OCD
Fulltone Fulldrive 2 MOSFET
many others...

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