i am building a box for 1 18" btl, going to be about 8 cu.ft. (actual is 8.02409) and tunned to 32 hz. i have done the calculations and does a 10"H X 3.75"W x 7.24"L port sound right?

If it is a slot port (shares a wall with the side of the box), it can be shorter.

Use this:

http://www.carstereo.com/help2/Articles.cfm?id=31

That is not much port area for a BTL 18. You would be better off with 7 ft^3 and more port area. At least 80 in^2, and 100 in^2 would be better.

thanks, yea i should have done some more math before i posted this cuz i realized that the port is wrong, i think i did use that website to help me and my friend told me to use the one on realm of excursion, the pencil and paper 101

ygpm.

I would do the 39"w x 27"h x 16"d box, and double baffle. I'm just assuming the port and sub will be up, if so a port 14.5"h x 6.5"w x will give you ~94" of port area. If you make it 19-20" long with a slot port you wont have to put a bend on the end (I'd lean toward 19), and it should be right between 32 and 33hz- close enough it won't make much of a difference. I did those measurements by that online calculator^.

You should end up with close to 6.7ft net after all displacement (rough #)

Edited November 13, 200717 yr by tejcurrent