No, Crutchfield aquired those specs from Alpine directly because they don't specify a vented box for those subs. As such the information reads that within the range of box sizes(0.6-1.25 cuft), Alpine recommends 1.0 cuft with a 3"x12"(sorry I think i said 10" earlier) port. I read that as gross box volume including driver displacement, and port volume. Therefore, I would build a 2 cube gross internal box with 170 cu inches of port volume. This will yield the same tuning and performance as their recommended box. Note: because the round ports' cylinder wall takes up very little volume, and your slot port wall will take up more(depending on wood thickness), you should add the port wall volume and any other internal bracing that you add for strength to the gross internal volume. Hope that clears it up for you.

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2004 300M SPECIAL
Alpine CDA 9833
Alpine Pxa-h701
Alpine Rux-c701
Rockford fosgate p400-4
Rockford fosgate p4004
Hifonics BX 1205D
JBL c608 GTi
JBL p963
Infinity 2.5" center channel
Alpine type R 12"(2)
200 amp alternator
yellow top battery
0 awg power and ground (welding cable) 300 amp anl fuse
all active SQL set up with 2000 watts rms