The SS4VC designed to connect four and six pairs of loudspeakers, respectively, to one receiver or amplifier. Each pair of speakers can be independently turned on/off. The volume control knobs give you independent volume control in all speaker locations. These systems provide impedance protection whenever its protection circuit is manually engaged by the user.When engaged, the SS4VC adjust the impedance load presented to the receiver or amplifier.With most amplifiers,when multiple speakers are engaged, the protection switch should be engaged. With high amplifier volume, your SS4VC switcher may become warm. Do not operate your system below the impedance rating of the receiver, amplifier, or the switcher. Check the owner’s manual of your receiver or amplifier. Do not exceed the 75Watt RMS rating of the SS4VC.