SD-1 Super Overdrive

Name: SD-1 Super Overdrive
Brand: Boss
Availability: OnlineOnly

Overdrive

The yellow screamer - asymmetrical clipping and mid-hump loved by blues and rock players since 1981.

The yellow SD-1 hit the market in 1981 as an upgrade to the OD-1, adding a Tone control to the original's two-knob layout. It became one of the longest-running pedals in Boss's lineup and a staple of 80s and 90s rock.

The circuit uses asymmetrical clipping with one silicon diode on one side of the feedback loop and two on the other. This creates an unevenly compressed signal that feels more amp-like than symmetrical designs. A natural mid-hump around 800Hz pushes your guitar forward in a mix without sounding nasal, making it an excellent boost for tube amps.

Level, Tone, and Drive. Roll back the Drive for a clean boost with midrange push; crank it for creamy, sustaining overdrive. The Tone knob adds bite at higher settings without getting ice-picky. 5mA current draw means battery life is measured in weeks.

Zakk Wylde ran an SD-1 into a Marshall for his signature howl. Richie Sambora and Warren DeMartini kept them on their boards throughout the 80s. Often compared to the Tube Screamer, but with a slightly grittier, less compressed character.