VocoPro DA-3700-BT 200W Digital Key Control Mixing Amplifier with Bluetooth Professional rack mountable digital karaoke mixing amp with 200 watts of total power Great choice for use in bars, churches, schools, and clubs as well as in-home systems 9-step Digital Key Control; effect loop for integration of outboard effect units 2 unbalanced 1/4-inch microphone inputs 2 switchable RCA A/V inputs for source players