Ported
They are comparable to the bandpass boxes because Bandpass Boxes have Ports. Yes, they get way better SPL then sealed boxes but it is at the cost of Sound Quality. If you can make a good ported however, the SQ won't take such a mean hit. There are many books that tell you how, some companies post Box plans on their website like JL Audio has a couple of different plans on their site, but other then that you have to draw up your own plans.
Hope I've helped.
1994 Probe SE
HU: Alpine 7893
Front Stage: JL XR 6.5" CSI
Rear: Who Cares....
Speaker Amp: JBL 180.2
Sub Amp: Avionixx 500m
Sub: Elemental 12O.44 getting 500+ watts
EQ: Audio Control
80 Sq feet of deadener
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