Brand new, unopened MACKIE Big Knob Passive Monitor Controller Speaker Maximum Output: 1000 Watts Frequency Response: 20 KHz Connectivity Technology: USB Audio Output Mode: Stereo Input Voltage: 120 Volts A very simple 2 x 2 monitor controller that requires no power. You can switch between two pairs of speakers and two sound sources to enjoy your music. Select from two stereo sound sources and two stereo monitor speakers. Inherits the volume control of the original Big Knob. Professional-grade mono, mute, and DIM switches. Sound faithful to the original source.