Jim Dunlop MXR GCB80 High Gain Volume Ped Pedal Effect

This gold standard of volume controllers is great for pedal steel swells and instant dynamics.
Quiet operation and heavy-duty construction combine with an ultra-sensitive 1 million cycle taper potentiometer for the most delicate control ever.
Power: passive in-line circuit requires no additional power
• Great for pedal steel swells and instant dynamics
• Quiet operation and heavy-duty construction
• Ultra-sensitive 1 million cycle taper potentiometer