Boss HM-2 Heavy Metal pedal

Boss HM-2 Heavy Metal pedal

• 4 Control Knobs: Level, Color mix (Low, High) and Dist.
• Connectors: Input, Output, AC Adaptor
• Input Impedance: 1MΩ (FET input)
• Recommended Load Impedance: more than 10 kOhm
• Recommended AC Adaptor: ACA Series
• Current Draw: 10mA (DC 9V)
• Weight: 400g
• Dimensions(mm): 70(W) x 55(H) x 125(D)
• Dimensions(inches): 2-3/4(W) x 2-3/16(H) x 4-15/16(D)

ICs, transistors and diodes used in the HM-2:

• IC1-IC3: M5218L or NJM4558S (dual operational amplifiers)
• Q1,Q4,Q5,Q10: 2SK30A-Y (Silicon N-channel JFET transistors)
• Q2,Q3: 2SC732TM-GR (NPN silicon transistors)
• Q8,Q9: 2SC945-P (NPN silicon transistors)
• Q6: 2SC2240-GR (NPN silicon transistor)
• Q7: 2SA970-GR (PNP silicon transistor)
• D1,D3,D5,D8-D12: 1S2473 (switching diodes)
• D2: S5500G (400V/1A rectifier diode)
• D6,D7: 1S188FM (Germanium diodes)
• D13: RD5.1EB-3 (5.1V Zener diode)
• D14: SLP135B (red LED)

The Boss HM-2 Heavy Metal pedal generates a unique distortion effect specially designed for Heavy Metal music. It has an interesting design with both asymmetric soft-clipping diodes, hard clipping diodes and a Ge diode pair in series with the signal for crossover distortion and simple noise gate. A wide variety of tone color creation is made possible with the 2 color mix controls.