Ok how about this then...
W = 37
H = 15
D = 20
Port opening = 3.5
Square point length = 15.75
Square point length 2 = 4.5
This would be 4.405 cu ft
30.08hz
With bracing and speaker displacement would I be at 4 cu ft?
Also, at 30hz instead of 33hz would that just mean that lower bass would be louder?
Or if I change...
Port opening = 4
Square port length 2 = 5
That would be 4.279 cu ft
and 32.06 hz