U r not giving enough info.
How much is that Rockford putting out?
I have two of those with an old MTX BLUE THUNDER PRO 3002, on a sealed enclosure and they sound pritty good (600-750 watts)//content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif
I will say anything between 300-400W per sub will be good.
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