Rolls DB228 Passive Wall Direct Interface for Standard Electrical BoxThe Rolls DB228 Wall Direct Interface is a passive transformer isolated direct box, which mixes an XLR microphone input with an unbalanced 1 8" stereo input to a screw terminal pluggable strip. The interface is ideal for impedance matching any consumer level audio signal such as CD, DVD, and MP3 players to a professional audio system. The Rolls DB228 offers a level control and will pass phantom power. The Rolls DB228 can be mounted into an optional