My sub is connected via rca cable albeit a very thin one. I do plan on replacing it with a thicker guage, but was wondering should I buy the best rca cable I can find or what? I know any cable is better than one I have, just wondering how good I need to have for best signal to the sub. Also, my speakers are connected with 16 guage acoustic research cable. Is 16 guage ok, or would you go thicker? Furthest speaker would be close to 40 ft of cable away.Thx for help.