I have been looking at the RE Audio SX18D2 (18" sub @ 2ohm) and have been trying to see if a box for it would fit in my cars trunk. It requires a 5.5ft.^3 box to 8.0ft.^3. In the screenshot below is a box made off of their website in the box calculator software. Would this box work well being 14" tall, after all the mount depth of the sub is 9.5" or 9.75" I can't remember. The height in the trunk is 17" so I figured a 14" would be fine. How would I find out how many hertz the box is, or better yet would someone be able to calculate that for me. I have been looking at many different subs and am still getting ideas, I just want to see if this is possibility that would work.