The 1981-1988 Boss SD-1 Super Overdrive is a highly coveted, vintage guitar effects pedal manufactured during the iconic "Made in Japan" (MIJ) era. Celebrated for its unique analog circuit, this specific year of production is a holy grail for collectors and tone purists looking to shape their midrange with classic, tube-like saturation.

Overall cosmetic condition is Good while the interior, battery compartment and play-wise it is in Excellent condition and fully functional

Technical Specifications

• Clipping Type: Asymmetrical clipping (utilizes a 3-diode layout).
• Operational Amplifier Chip: Features the legendary JRC4558DD IC.
• Power Requirements: Original 12V DC ACA power supply or a standard 9V battery.
• Enclosure Details: Distinctive "Black Label" on the bottom plate with a stamped 6-digit serial number inside the battery compartment.

Sonic Characteristics

Unlike its main competitor from the era—the Ibanez TS9 Tube Screamer, which uses symmetrical clipping—the 1983 SD-1 delivers a slightly raspier, more aggressive edge. It pulls back the low-end frequencies while boosting the upper-midrange. This distinctive "mid-hump" cuts cleanly through a live band mix, making it ideal for pushing a dirty tube amplifier into high-gain territory.