The problem with Alpine is their slot port volume specs are different than their tube port volume specs by quite a bit, at least for the new type R's. Normally, you just have to take the radius of the tube port, in this case 1.5", square it and multiply by Pi( 3.1415). This yields, 7.068 square inches of port face x the length= 70.68 cubic inches of port volume. You then divide that by your slot port dimensions. eg. 70.68/11(port height)=6.42/1(port width)=6.42 which equals your port length. This will give you the same mass of air to move in your port and should give you the same tuning as the round tube port. Unfortunatly, Alpine has not specified a slot port for these subs, but they do for the new models, and the slot and round volumes are very different.

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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