Nady ADI-2 Two Active Direct Inject Box Features: Simultaneous dual inputs and outputs for stereo or multi-source use Eliminates impedance mismatch problems and converts any sound source at almost any level (from guitar to speaker) into a clean, powerful hum-free, noisefree and interference-free balanced signal perfect for even extremely long cable runs Full-featured controls and connections include On/Off, Ground Lift, and Guitar/Speaker Source Select input attenuation switches; unbalanced 1/4" TS Input and Parallel Link Output jacks; and servo-balanced XLR Output jack. Parallel link output allows ultimate hookup flexibility by enabling applications such as connection to the input of the backline or monitor amplifier. No compromise circuit design and stringent component selection provide absolutely flat, full frequency response across the entire audio spectrum, and negligible distortion for the most natural, powerful audio available. Portable aircraft aluminum extruded case for ultimate roadworthiness, long life and reliability Powered either by console's +48V phantom power or internal 9V battery