The Boss DM-3 Green Label made in Japan in the early 1980s vintage analog delay pedal, known for its warm, organic repeats, similar circuitry to the DM-2 but with added high-speed noise reduction and an extra filter, featuring standard controls (Repeat Rate, Echo, Intensity) plus unique controls for its era, offering both wet/dry stereo output options and running on 9V or ACA power. 

Key Characteristics:

• Analog Tone: Delivers classic warm, musical, and smooth delays.
• Green Label: Signifies its vintage "Made in Japan" production, typically from around 1984-1986, a hallmark of quality Boss circuits.
• DM-2 Successor: Built on the DM-2's foundation but with enhancements like a filter and noise reduction.
• Unique Controls: Features controls not found on other pedals, adding to its distinctive sound.
• Stereo Output: Offers mixed (wet/dry) or dual mono outputs for stereo effects.
• Power: Compatible with 9V batteries or ACA power supplies. 

Why It's Desirable:

This pedal is sought after by guitarists for its classic analog sound, reliability, and vintage status, offering rich depth and ambience to guitar tones. This pedal is in great cosmetic and operating condition and comes with the original box, as shown. Serial# 673200.

Understanding ACA vs. PSA

The main difference between the old ACA adapters and modern PSA adapters (Boss's current standard) is the voltage and regulation type. 

• ACA Adapter: This was an unregulated power supply that would deliver around 12 volts DC under the low current draw of vintage pedals. The pedal itself contained a simple circuit (a resistor and a diode) to drop this to the required 9 volts.
• PSA Adapter: This is a modern, regulated 9-volt DC power supply. 

Important: Using a modern 9V PSA adapter (or any standard 9V supply) with an unmodified ACA pedal will result in underpowering, causing the LED to be dim or off and the effect to sound weak, as the internal circuit drops the 9V further down to about 6V.