DI INJECTION BOX 'Ideal for active instruments such as guitars and basses with active pickups and preamps, the MDB-1A Active DI offers increased clearance and distortion-free performance. Featuring a 1/4 '' high-impedance input and a -20db pad plus a Merge switch that turns the Thru jack into a second input, perfect for adding a stereo source to a mono output. The balanced XLR output features switches for Polarity, Low Cut and Ground Lift. For maximum convenience, the MDB-1A operates on 48v phantom power. '