Boss SD-1-4A 40th Anniversary Super Overdrive Pedal

Celebrate 40 Years of BOSS’s SD-1 Super Overdrive

Back in 1981, BOSS unveiled their workhorse SD-1 Super Overdrive, a core gain pedal that has been subsequently wielded by generations of players across genres. The BOSS 40th Anniversary SD-1 Super Overdrive celebrates four decades of this classic stompbox, vaunting the same asymmetrical clipping circuit, along with a head-turning reverse color scheme that will stand out on even the most crowded pedalboard.

SKU SD-1-4A Category Tags ,


The SD-1 has long been renowned for its mid-focused tone and natural tubelike overdrive characteristics. It’s ideal for warming up or adding grit to a clean or edge-of-breakup tube amplifier, and it’s a great way to add tightness and definition to a high-gain setup. It also makes a stellar lead boost and stacks well with other dirt pedals. If you’re searching for a drive stomp with a rich, harmonic-infused tone, join the legions of satisfied guitarists who build their sound around the SD-1. Grab the BOSS 40th Anniversary SD-1 Super Overdrive today!

Asymmetrical clipping: the secret to the SD-1’s one-of-a-kind sound

Unlike the symmetrical clipping employed by its green Japanese-made competitor, the BOSS SD-1 makes use of asymmetrical clipping. The difference is subtle yet significant. Symmetrical clipping generates odd harmonics for a round, compressed, smooth-sounding tone. Asymmetrical clipping produces both even and odd harmonics, yielding a deeper, clearer, more textured sound. Asymmetrical clipping tends to sound louder as well. What’s more, many guitarists prefer the tubelike feel of asymmetrical-clipping overdrive pedals like the BOSS SD-1.