Just wanted to verify my final box design before I build. Going for 3.5 cubes @ 33 hertz. My box will be 35 wide x 16 high x 18 deep, sub up, port to the passenger side running along the bottom (3 high x 16.5 wide x 28.25 deep = 49.5 sq inches) . Just making sure my calculations are fairly close before I lay down some mdf whoop ***.

 

This site may help you figure out proper port size. By your measurements, your box will be tuned to about 30 Hz not 33 Hz. your port is too long, port should be about 21" not 28.25". Correct me if I'm wrong...

Port Calculator

 

Don't know how you got that, when I typed it in there it gave me 27.7

 

I swear by that calculator. I got results similar to Danny D's:

 

I see the difference, I went 16.5 inches HIGH by 3 inches wide. That is a huge difference, which one is correct?

 

That's quite odd... you'd think it would give the same depth since its the same area.

 

I think for simplicity sakes I am going to go sub and port up, pushed as far back as I can. That way I can mount my amps to the back of the box and have access by folding down my seats.