Havent got my amp in yet, but my buddy with a kicker kx1200.1 came over, so i took the chance and talked him into putting the FI q in there to hear it for the first time. My box, b4 speaker displacement, is 2.5cu/ft tuned to 32.2hz. I do have the BP power option also I was thoroughly impressed with both the sound quality and the output of the Q. I kept reading everybody state that if you want "loud" to go with the BL, but i dont see this really being a factor with the Q. I understand teh BL is more directed for spl than SQ like the Q, but i was very impressed at the output of the Q, and did not expect it to be that loud. My buddy who owns the car said the Q was louder than his 3 infinity perfect 12's in a sealed enclosure, without changing any settings on the system I would recommend this sub to anybody who has thought about buying it. Just makes me wonder how much louder the BL and BTL actually are in comparison, because how many people downplay the Q in regards to output. will def purchase more FI products