I bought this as an overdrive, now it's always on. It makes any amp sound... "more" — It gets the speaker moving, it simply drives the sound of your setup in a lush way. This Klon can add colour, and it will. Roll off the drive and you just get a lovely clean boost, and the tone control dials in that mid hump to how you like it, Quasimodo to Old Lady Hump. Overall, I'd recommend it but I'd like a slightly different EQ option.