dont go with rockford. rockford sucksssssssssssssssss. stick with alpine or jl.
http://www.crutchfield.com/p_500MRPM...cid=1586526400
i say go with that amp. and run both subs into the same speaker slots or get a 2 channel amp and bridge it. but this is the same thing. im running a 2 channel alpine amp bridged to my 1 10 inch sub and it hits hard. i also tried a 1 channel amp with 2 subs and hit just as hard and then you dont have to synchronize the subs or anything.