What gauge of wire to use on a home speaker?

Long runs of power wires have issues. The issues are reduced, but not eliminated by using thicker gauge wire for longer runs. On a highly sensitive music system you can detect a tiny difference over 15 feet using 12, 14 and 16 ga wire. Home Theater sound is not music and chances are you dont use $1800 electrostatic speakers all around so in reality you can get away with thinner wire for movies. But my system is wired with inexpensive but decent oxygen-free 12 ga. I just bought a spool of it from a speaker building site like www.partsexpress.com. I had a spool of generic Radio Shack wire in a box and one day I was going through the box's and found the spool still in plastic. The wire had all turned dull brown visible through the see-through insulation. This stuff was not oxygen-free so the wires had started to oxidize right after being manufactured. Oxygen free simply has a neutral gas sprayed over the copper during manufacture so oxygen does not get a chance to attack the surface while the copper is molten. This increases the life of the wire dramatically, but only increases the price of the wire by a few pennies per foot. Hope this helps.

It depends on how far away your reciever is from the speakers, and what type of impedance your speakers present to the amp... the longer the run the thicker the wire needs to be...check the link below for guidance on what guage to use for what length of a run you have....