Most systems will use 16, 14 or 12-gauge AWS wire. 16-gauge copper wire can run up to 48-feet with 8-ohm speakers. So, if you want a wire size that will suit most circumstances, then a 16-gauge copper wire is probably a good fit. For speakers with a lower impedance, then you might go with 12 or 14 AWG just to be safe.

Copper

For the best quality wire, looking for something made with 100% copper is highly recommended. However, if you’re looking to save a bit, copper-plated or copper-clad aluminum wire is a fine substitute, and there is no noticeable difference in sound quality.

To answer the question posed at the start of this article – yes, you can use a regular electric wire as a speaker cable, as long as it comes with two same-sized conductor wires.

Speaker wiring is of much heavier wire gauge due to the current that they have to carry. USB cables are of much thinner/lighter gauge because they are meant for carrying electrical signals of very low power.

Yes you can mix 12 and 14 gauge wire with a 15 amp breaker on the circuit. But it is not recommended because the next homeowner or electrician may be confused and put a 20 amp breaker on it again.

You can not use 14 AWG anywhere on a circuit that has a 20A breaker. If you are putting 15 amp receptacles on a 20 amp circuit with 12 gauge wire, then you MUST use the screw terminals, not the back stab terminals.

10 receptacles

Wire Size & Amp Ratings

20 Amps

12 outlets

14 AWG wire has an ampacity rating of 15 amps.

15-amp vs. In a way, it all starts with the size of the wire. 14-gauge wire is the smallest allowed for the permanent wiring of a circuit. It is rated as able to carry up to 15 amps of current. 12-gauge wire is the next size larger and is allowed to carry up to 20 amps.

Maximum current – amps – through a 12V circuit – related to size (AWG) and length of wire