With the Electro-Harmonix Operation Overlord Allied Overdrive, whether you play guitar, bass, keyboards, or pretty much any electronic instrument - dialing in great drive sounds is fast and foolproof. Active 3-band EQ controls, footswitchable BOOST mode, and a dry blend provide versatility for different tones and instruments. The OVERLORD also features two independent distortion channels for use with stereo setups. Whatever your rig, the Overlord is your indispensable ally. Controls The GAIN knob controls the amount of overdrive and distortion. As you turn GAIN clockwise, the amount of input gain increases. The BOOST knob controls the amount of extra gain fed into the main circuit when the BOOST and NORMAL modes are engaged (both LEDs lit). As BOOST is turned clockwise, the amount of distortion increases. The DRY knob mixes a clean unaltered signal with the distortion produced by the OVERLORD. At the minimum position of the DRY knob, the output is 100 percent overdrive effect, and at the maximum position, the output is 100 percent clean. This function is useful for preserving the harmonic integrity of your playing, which is especially useful for keyboards or bass. For guitarists, this feature can be useful if you are stacking the OVERLORD with other drive pedals, or are playing it through an overdriven amplifier. The INPUT LVL switch controls the overall input level of your instrument into the OVERLORD. Use it to set an appropriate gain level for a variety of instruments. Set the switch to HI for low-level instruments, like a single-coil guitar or vintage electric piano. Set the switch to NORM for humbucker guitars and most modern keyboard workstations. Use the LO setting for high-output instruments, like some synthesizers or boosted guitars. BASS Knob provides active control of the level of the bass frequency range. MID Knob provides active control of the level of the middle-frequency range. TREBLE Knob gives active control of the level of the treble frequency range. VOL Knob controls the overall volume output of the OVERLORD. As this knob is turned clockwise, the output level increases. BYPASS Footswitch and red LED selects whether the OVERLORD is engaged or in buffered bypass mode. When the effect is engaged, the red LED will be lit. BOOST Footswitch and blue LED toggles Boost mode on and off. When in Boost mode, the blue LED will be lit.