this is parallel-tuned, aperiodic-coupled bass reflex. It can play from quite low and to quite high. Good for pop, disco music. It really punches from the back...lol

i have a kicker cvr 8 inch sub, with a nice box, plays like 12 inch amp that feeds the sub is about 250 @ 4om, the sub is only 150 rms. my car roof is shaking badly