The Mackie MDB-2P is a stereo passive direct box designed to connect two mono instruments or a single stereo instrument to microphone preamps for musicians and audio engineers in recording sessions, houses of worship, and live stage applications. It converts high-impedance, instrument-level signal via its 1/4" TS unbalanced inputs to low-impedance, mic-level outputs via balanced XLR 3-pin jacks. Two 1/4" TS thru jacks allow simultaneous connection to amplifiers or pedalboards.

Each channel offers a -15 dB pad for reducing the input level to prevent distortion when using a high-gain source. The ground-lift switch inhibits hum caused by ground loops. Due to passive design principles, the MDB-2P requires no batteries or power supply. Its sturdy steel chassis enables confident use in the studio or on the road.