heres some advicei know u like your box now cuz a box that big even tuned to 35hz will have decent authority in the low end....assuming u have it tuned no higher than that and sealed the box as well as u can
but my suggestion...your next box make it 24wide x 14high x 14deep...thats around 2.7cubes...after port and sub displacement.,u should alittle over 2cubes
and u will be able to fit it behind your seats instead of a box that takes up half your seat....and on you new box make sure the sub is up and the port is facing the hatch
i gave u 3 tips
1-make your box smaller(24wide x 14high x 14deep)
2-sub up port facing the back
3-tune it anywhere from 35hz and lower
otherwise for your first build...it looks good...alittle more projects and u should be fine
u should build your next box to get more practice
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