Ahh the vented boxes.....I hate rap too but if you really want to know how good your subs/box is, try playing "fermin 4" or rammstein.
fermin 4 has a lot of low level bass and rammstein has some good metal + double bass combo.
Try it...
(ps: i have a 96L double vented box with fosgate subs)
Cheers
Jake
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