Boss SD-1 Super Overdrive

The Clipping Circuit That Defined “Overdrive”

In 1977, BOSS created an entirely new stompbox category with the OD-1, bringing natural overdrive in pedal form to guitarists for the very first time. Producing a signal rich in even-order harmonics, its unique asymmetric clipping circuit replicated the pleasing sound and feel of a driven tube amp—but at controllable volume levels. Four years later, this breakthrough design evolved into the more versatile SD-1, which added an active tone control for shaping the treble response and subtle enhancements for more low-end body.