Up for sale is a completely original, vintage Boss CS-1 Compression Sustainer in good cosmetic and perfect working condition.

According to the internal 6-digit serial number (073800), this unit was manufactured in June 1981 at the famous vintage Roland/Boss factory in Japan.

Unlike the later VCA-based CS-2 and CS-3 models, the CS-1 utilizes a highly coveted, unique analogue optocoupler circuit. This design gives it a distinctly warm, musical, and smooth compression character. It also features the iconic "Treble/Normal" toggle switch, allowing you to instantly cut through the mix or add chime to dull pickups.

Key Details & Condition:

• Production Date: June 1981 (Serial #073800)

• Hardware: Features the period-correct, authentic black plastic factory thumbscrew from the mid-1981 transition era.

• Cosmetic Condition: Good vintage condition. It shows some honest, minor play wear and small paint chips along the edges—exactly what you want to see on an authentic 45-year-old pedal. The faceplate and labeling remain clean and highly legible.

• Electronics: 100% original circuit and fully functional. Both knobs operate smoothly without any scratchiness, the toggle switch clicks firmly, and the battery terminal/footswitch work perfectly.

Note: This is a vintage Boss pedal designed for the original ACA 12V power supply. It runs perfectly on a standard 9V battery, or via a modern 9V daisy-chain setup.

Shipping securely tracked and packed. Feel free to shoot over any questions!