DigiTech DGR Grunge Analog-Distortion Guitar Effects Pedal Level (Loud) controls the distortion output level of your guitar signal. Low adjusts boost and cut of bass frequencies. High adjusts boost and cut of high frequencies. Gain (Grunge) controls distortion gain from moderate to extreme. Dual Outputs. The Amp output is for connecting directly to a guitar amplifier. The Mixer output features Cabinet Emulation circuitry for connecting directly to a mixing board or recording device.