Extron XPA U 1004 SB is an ENERGY STAR qualified four channel audio power amplifiers with flexible channel pairs that can drive 8-ohm, 4 ohm, 70 volt, or 100 volt loads. The individually bridgeable pairs can deliver two 100-watt channels into low impedance systems or one 200-watt channel into low or high impedance systems. A rotary switch on the rear panel makes it quick and easy to select output mode. The convection cooled, plenum rated enclosure of the XPA U 1004 SB does not require empty rack spaces for ventilation and includes rack mount hardware. It features a highly efficient advanced Class D amplifier design with defeatable auto standby, fast wake up from standby, and our patented CDRS Class D Ripple Suppression. XPA Ultra SB models also offer remote volume and mute control with Extron VCM, VC or select MediaLink controllers.