ADCOM GFS-3 Speaker Selector Switch, 3-Zone w/ Protection, Original Box Manual

The GFS-3 gives you the flexibility to run up to 3 pairs of speakers off a single amplifier output (up to 200 watts per channel). Its built-in Minimum Impedance Protection circuit is designed to protect both speakers and amplifier without sacrificing sound quality — preventing the low-impedance loading problems that can cause distortion or amplifier shutdown when running multiple speaker pairs simultaneously.

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