Check out table one in this article
http://www.audioholics.com/audio-video-cables/speaker-cable-gauge
Depending on the speaker Impedance, you might want 12 AWG. I used Blue Jean Cable for my surrounds
http://www.audioholics.com/audio-video-cables/speaker-cable-gauge
Depending on the speaker Impedance, you might want 12 AWG. I used Blue Jean Cable for my surrounds