the truth is... the subwoofer has very little to do with the sound you achieve from it... the set-up actually says more about than the sub itself. The sub determines the performance of the set-up... If you want a sound that is smooth and rangy go for a venter sub box... if you want more boom for the buck go for the sealed box set-up... if you don't have a crossover and just wants to have a nice sounding box, go for a isobaric box... just check the thiele-small paremeters for your sub and choose the one that matches you speaker... hope that helps...
