Re: Box design
Why did you opt to build 4 chambers?
Did you model this box for the Hifonics subs or some future planned upon replacements?
Assuming you're using 3/4" material, you can't have 14" OD and 14" ID. If the box is 14" tall, internal will be 12.5, assuming only one layer of baffle, which isn't recommended. Also with ID/OD... 36.5" width and depth would be 35" internal. Accounting for internal braces, you end up with 2.12ftⁿ per chamber before port and driver displacements, which is fine. Also, port area is fine for the Hifonics drivers you listed but wouldn't be enough for a driver with some real xmax. The Hifonics subs only have 6.5mm.
Also, I don't think the port up sub up combination is going to sound good in a trunk car.
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