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A lot of friends as me the question What is speaker cable gauge ? It's the size of the wire used to transmit the electrical energy from an amp to a speaker.
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Kindly note output watts doesn’t really matter here, it’s the distance and speaker impedance which need to be matched. Thick wire (12 or 14 gauge) is recommended for long wire runs, high power applications, and low-impedance speakers (4 or 6 ohms). For relatively short runs (less than 50 feet) to 8 ohm speakers, 16 gauge wire will usually do just fine. I personally use 16Awg wire in my stereo setup. Refer below link for more details.
How to choose the right gauge, length, and type
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