Summary: Purchased these for my Lincoln LS, I put them in a non-ported box. They hit well with my 1400 watt rockford amp. I thought they would blow with all that power, so I sold them to a friend, and purchased 2 jl audio w6 subs.
Summary: To me Rockford Fosgate is the best sub money can buy. When you put these subs together with the right Fosgate amp you will be more than satisfied with the bass I promise you. I replaced the bose single sub in my car with this fosgate and it sounds better than alot of cars with two subs.