The dbx dB12 is an active direct box that utilizes custom dbx mu-metal-shielded audio transformers, high-quality Neutrik connectors, and low-noise circuitry. The dB12 direct box includes a pad switch that accommodates instrument, line, and even speaker level signals. Take even more control of your sound by utilizing the dB12 direct box's polarity invert switch to set the phase relationship between the direct and mic'd sound.As a professional, you don't have time for interference, so dbx includes a ground lift switch in the dB12 active direct box to solve potential hum and buzz problems due to ground loops. And between the combined shielding of the cast metal chassis and the custom-wound transformer, you can be doubly assured of a clean signal free from interference. All of this sits atop a solid, stable footprint, that will keep the dB12 direct box from being dragged around the stage. Unique contoured underside allows secure stacking of multiple dbx dB12 Active Direct Box units.