The 2-channel Xotic AC Plus pedal combines their popular AC Booster circuit with a highly flexible preamp. Channel A's Tone knob attenuates your mids and highs. The Boost button increases your lows and mids by 3dB, injecting your tone with extra grit and volume. Channel B's 3-band EQ creates plenty of sound-shaping options. The Comp button selects between Hard clipping, which yields early breakup and smooth overdrive, and Soft clipping, which offers late breakup and abundant headroom.