The Russound P125 is a 2-channel dual source power amplifier with auto-source switching. It features Primary and Secondary audio line inputs with a loop out to another zone, receiver, or device from the secondary source. A speaker-level input can be connected and assigned as either the primary or secondary source. This amplifier can be used for power upgrades in zones for large speaker selector or volume control systems. The P125 is rated at 125 watts per channel into 4 ohms, and 80 watts into 8 ohms. With the Stereo/Bridge Mono switch in the Bridge Mono position, both amplifier channels are combined for a higher powered mono output. In Bridge mode the X125 is rated at 250 watts of power into a single 8 ohm load. The 12V Trigger In/Out allows the amplifier to be activated by other devices or to activate other electronics via a 3.5 mm mini phone plug cable, with 100mA current capability.