Ok, so I measured my trunk today... or well... how much space I'll have to get the box in and out of the car when it's fully built. The dimensions (DepthxHxW)I have to work with are 12x16x40 (3.39 interior cu ft if using 3/4" mdf), 16x16x40 (4.68 cu ft) and 16x17x40 (5 cu ft). There are 3 different measurements for 3 different scenarios of how I want the box built. The first one is if I want the box to fit under the part right behind the fold down seats. The second is if I don't want it to. The third is if I take the the rear speakers out.
Now, here's my main reason for needing help. I am trying to design a box that will be ported and mainly designed for SPL. However, I'd like to be able to hear the sub (DD 9012) without any SQ loss with the seats up (they kind of muffle sound). So I was thinking I could use the speaker holes as area for ports. Someone I talked to about this suggested using round port tubes. I can see why he suggests that as the speaker holes are oval shaped. What I want to know is if I should use 2 ports, one in each speaker hole, or just 1 port? If I only used one, I could put the sub facing upwards underneath the unused speaker hole. Does anyone have any better ideas or suggestions about building this box?
I have the following stats for the sub:
BL PRODUCT 25TM
FREE AIR 31HZ
I think the recommended ported box size is around 2.5 or 2.75 cu ft.
I can take a picture of my trunk if it helps anyone visualize what I want to do. And I'm planning to get a Hifonics Brutus 1500 amp for it once I sell my old system.