Since its release in 1981, the SD-1 Super Overdrive has influenced generations of musicians. A true workhorse, the SD-1 is the gain center on countless pedalboards across a wide range of musical genres. Based on the revolutionary, asymmetrical clipping circuit of the OD-1 Overdrive - one of the first three BOSS compact pedals from 1977 - the SD-1 delivers dense, smooth and extremely musical overdrive sounds that have lost none of their inspirational power to this day.