The subs are Alpine type-R. I was thinking of actually letting circuit city do it. The seem to really know their stuff and had a bimmer being worked on at the time. I figure its not a custom box or anything so how hard can it be right?
everything being equal a ported box will yield a 3dB increase in sound over a sealed box. A ported box is generally (not always) roughly twice the size of a sealed box. Ported boxes have a narrower roll off the a sealed box, not nearly as smooth, but will provide more (boom) in a specific range (say 45-60Hz) sealed boxes generally need more power than a ported box as well, but the subs will generally last longer. If the port isn't sized correcly you run the risk of hearing port noise as well. from my experience w/ Alpine (I sell it) I would recommend sealed. good sound, longer life, more trunk space for you, and, well, it's pretty damn hard to screw up a small sealed box. a prefab is fine, just make sure you stay within the volume stated in the Alpine lit for your speaker & you'll be set.
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