for a sub. an ED nine.1.http://www.edesignaudio.com/product_info.php?cPath=1_22&products_id=44 if i didnt get the 5ch i would have got this for sure.
the nine.1 is a beast. its rated 1200rms@12.5v and if you have a good electrical system then you'll be seeing 13.5-14.5v~. which means closer to 1600-1800rms~