Originally Posted by NoTLaDStyle
Look at the attatched graph:
Using the MTX recommended enclosure sizes for sealed(yellow) and vented(green) enclosures, you get an identical response curve BUT the vented box gives you almost a 10hz lower response That is the extended range without loss of quality.
The blue was me messing with the ported specs. Its too boomy

FYI Too Boomy means its not accurate. Hence the "TOO". If you play and like boomy music, you cant get too boomy, so that is great if everything you listen to sounds like sss sss booom sss sss booom.
Remember, you can tune a sealed box as well, bigger box=lower bass. Add a cubic foot and see where the bottom end of the sealed box ends up.