Hmm, on my bandpass both chambers seem to be ported?

 

You would have a port for each woofer... you could have multiple ports for each woofer depending on the design.
Bandpass boxes are very difficult to create to custom tailor the sound..generally pre-fab bandpass boxes wont be made specifically to your woofer's specs.

I recommend the sealed box and a good woofer. What's your price range? or are you sticking with your xplods for now?

Bandpass:
(# of ports are all for design and what freq. to be tuned to... so dont assume you need "x" number of ports for "x" number of woofers)




Ported:
http://www.thezeb.com/images/brands/...ubzoneZbox.jpg

Sealed:
http://www.thezeb.com/images/brands/subzone/HJ121.jpg

Boxes come in all sorts of shapes.. some have plexi windows to show off the magnet/driver...

Prefab boxes like Subzone......Q logic... sealed.. will be your best bet.. find out the woofer's volume requirements and match that up to the box's volume..

 

I'm probably just going to go with the Basslink - it seems very compact, and stuff I listen to doesn't require much boom. I'm just wondering where to mount it inside the cabin, in a way that it doesnt take away from cargo space, and isnt easily visible to thieves.