I have a jbl bp600.1 amplifier, running a infinity 12w30 sub in 1.35 cfu sealed box. the sub is recomended for 1.25 free air space and the magnet takes out .1 of it..the kat at the store said as long as I was close with my dimensions I wouldn't be able to hear the diff..between a 1.35 and a 1.25 box..I went for the precise however.. the question is..jbl bp600.1 being a class D..as opposed to running an AB amp..how much difference in sound quality would there be if I were to purchase a clean AB amp to power the sub? sound quality is what I am after, not shaking down the lightpoles, what would be a good sub for to replace the infinty 12w30 with that would fit the above described enclosure ?(too lazy to make another) thanks for your help and time
He is right about the boxes, typically with sealed enclosures you won't hear a difference when it is only off by about .1 or .2 cu ft. There are plenty of subs out there that will work in that airspace, it depends on your price range. As far as the amp, you'll notice a difference, but the A/B amp will draw more current too, keep that in mind.