i wanted to build a box just like this one for 2 18" fi btl's this box in the pic is for the mtx 12"s i have now im putting it in a dodge caravan so i have pretty much a crap load of space i just wanted to know if any one has any ideas on dimensions that i would need to get it tuned to 31-33hz

http://img397.imageshack.us/my.php?image=g...tachmentpd2.jpg

Edited April 8, 200817 yr by dsgfierce1

Yes I have the perfect setup for two 18" BTLs. Internal dimensions are 18 x 30 x 48 port size 6 x 18 x 22. Comes out to 15 cubes before the port. I hit a 147.1 at 42hz with 1500 watts a sub. If you look at my setup in my signature The test was done with 2 of the 4 3000Ds strapped at four ohms. I'm a Bass Racer and tend to baby my equipment. For pics go to myspace.com/demonaudio and look in the Fi-150 v 2 album. Good luck with your build! Oh yeah my port is to one side just move it to the middle.

thanks man just for kicks what do you think about a 25x25x47 with a 6"w 22"L slot port right in the middle of the 2 subs?

It would proly sound good. I tend to stay away from more sqaure chambers due to their tendency to create a standing wave. The chambers after the port would measure something like 20.5x25x25 also make sure that the port does not go closer to the wall than its width i.e. if the port is 6" wide then it needs to have 6" of clearance from the rear wall of the enclosure. This will alow for easier calibration when tuning the box. Hope it helps. Good luck on the build.

Edited April 11, 200817 yr by Fi-150man