Home Theater & Entertainment Audio 53 53 people found this article helpful How to Use a Speaker Selector Switch for Easy Multi-Room Audio Two hours and a simple switch is all it takes By Gary Altunian Writer Gary Altunian was a freelance contributor to Lifewire and industry veteran in consumer electronics. He passion was home audio and theater systems. our editorial process Gary Altunian Updated February 27, 2020 Ivan Stevanovic/Getty Images Audio Speakers Stereos & Receivers Tweet Share Email An external speaker selector switch routes signal from your receiver or entertainment center to any specific arrangement of speakers — regardless of the room they're in — that the switch can support. Internal Selector Toggles Your stereo receiver offers a built-in switch to toggle A and B speaker sets. This option supports a second pair of speakers, typically from a different room. The speakers set to the A switch might be meant for the main TV or movie entertainment, while the speakers set to the B switch can be set for music. Typically, the receiver can safely handle both sets operating at the same time. Some receivers also have multi-room capability to power speakers in as many as four rooms or zones in your home, although not all zones may be able to play simultaneously. Using a Speaker Selector Switch But what if you want to connect more, separate sets of speakers and wire additional rooms? The easiest and safest solution — which is often cost-effective for the budget-minded — may be to use a speaker selector switch. It acts much like a hub or a splitter, allowing users to connect and power as many as four, six, or eight pairs of speakers to a single receiver or amplifier. Some models also offer independent volume control over each pair of speakers. Not only does this kind of switch handle more speakers, but it's actually necessary to help protect the amplifier or receiver from damage. Low-impedance problems arise from playing multiple speakers at the same time. Amplifiers and receivers are usually rated for speakers that have 8 ohms of impedance (some are rated between 4 and 8 ohms, but 8 tends to be the norm). The impedance specification is important because it determines how much electrical current flows to the speakers, and connecting more sets of speakers increases the total amount of current. For example, if two pairs of 8-ohm speakers are connected and playing, the resulting impedance is 4 ohms. Three pairs results in 2 ohms of impedance, and so on. If the current flow increases too much, it can exceed the ability of the receiver. The result can lead to the receiver activating its protection circuit and temporarily shutting off, which can cause permanent damage to the amplifier/receiver over time. A better solution includes a speaker selector switch that also features impedance matching. This way, you can safely play as many as four, six, or eight pairs of speakers simultaneously while maintaining a total impedance of 8 ohms, thus protecting the amplifier and receiver. To use a speaker selector switch, connect the left and right channel outputs of the amplifier/receiver to the inputs of the switch. Then connect the various speaker sets to the speaker outputs. Depending on the types of speakers owned and where you plan to place them, it can take a few hours to run the speaker wires to all the other rooms in your home. Check the wire gauge specifications on the speaker selector switch first to make sure it's compatible (typically 14 to 18 gauge) with the speaker wires you plan to use. Match your speaker connection (e.g., banana plugs, spade connectors, pin connectors) to the speaker selector switch. Consider installing a volume control module between each speaker set and the switch. It requires a bit more time to do affect the wiring, but the upside is that rooms will have adjustable volume controls within easy reach. And if the speaker selector switch doesn't have its own labeling system for zones (many do), create your own labels and stick them above and below each switch. Choosing a Speaker Selector Switch A wide selection of speaker selector switches are available. A quick Amazon search shows a number of them that you can then compare for the features and price point you're after.