? It's a Muff, with additional controls over mids (cut and boost) and bass (cut), and the Pre knob allows you to affect the texture but it is a Muff with a huge range, not a generic "distortion." -EMusket is a good one if you want more of a distortion sound, the Hoof is great too.
Basic Audio Tri/Ram is the best Muff I've played through so far though. Mids knob helps it cut through the mix no problem.