When wiring back up my sub to the amp I ran out of the 12 guage I had before so I just used some left over 8 guage. From the sub to the connecting terminals on the box is 12 guage. I figured bigger was better. No problems as of yet. This isn't better or worse in anyway in the long run is it? My amp is using 4 guage power and 4 guage ground. Speakers use 16 I think.