A subwoofer is often placed away from the equipment rack, requiring that you plug your receiver into one AC outlet while plugging your subwoofer into a different outlet. You will also need to connect an RCA cable to carry the audio signal from the receiver to the sub. This creates a wired path between the two AC outlets, allowing harmful electrical surges and spikes to travel back and forth.
Panamax' MD2-RCA offers a clever, convenient solution. It has a protected AC outlet to provide safe, clean power for your subwoofer, plus protected RCA inputs and outputs. Also included is a separate module with its own RCA inputs and outputs that is designed to be placed with your components — you connect the two units with an RCA patch cable. So now, the audio signal path between your receiver and subwoofer is protected. The RCA module should be grounded to the ground lug found on Panamax line conditioners.