Mackie Big Knob Passive Monitor Controller Features:
 
Passive studio monitor controller
Passive electronics for ultra-low noise and maximum signal integrity
Connect two sets of inputs and easily switch between them
Supports two pairs of studio monitor speakers
Large volume knob for easy level adjustments
Handy buttons for Mono, Mute, and Dim
 
Tech Specs
 
Input Channels:2 x stereo sources
Output Channels:2 x stereo monitors
Analog Inputs:4 x 1/4" TRS, 1 x 1/8" (line in)
Analog Outputs:4 x 1/4" TRS
Form Factor:Desktop
Power Supply:Passive