Box for an 18" BL. 44.5" wide, 21.5" tall, and 20" deep. Port is 4.5" wide and 20" tall. Port length is 30" for about 30 hz tune and ~6.7ft^3 after displacements.

I've never built a ported box and never had a sub that heavy. I've seen people do "window" bracing like I drew here...think this 2" wide bracing be adequate? The sub will fire up and port back in my Explorer (read that is a general rule to go by), but I can turn the box for rear firing the sub and firing the port up if that works better. Thanks for any thoughts!

Edited October 4, 201212 yr by ImBob

I didnt check your measurements but the design will work just fine.

my only thought would be to double baffle the top at least. i personally over build stuff just to be sure that it is sturdy and safe. design looks pretty good though

to me those window type braces in theory seem like it would obstruck the free flow of air

how about a " + " shape brace instead

I wasn't sure if it needed a double baffle with the bracing, but I guess it makes sense to go ahead and do it just in case. I thought the window brace may be an airflow obstruction too, just didn't know if that would matter in a sub box. The + does seem like it'd be less obstructive though. Thanks for the opinions guys!

Why not dowel rod? It's cheap and effective. Plus its super easy to install.

Don't know what dowel rod is (I'm a noob), but I'll look into that. Thanks!

Edit : We talking wooden dowel rod?

Edited October 5, 201212 yr by ImBob

Don't know what dowel rod is (I'm a noob), but I'll look into that. Thanks!

Edit : We talking wooden dowel rod?

Yes.

Ok cool. Looks like Lowes has that so I'll get some when I get my mdf and stuff.

I had an enclosure pretty similar sub and port were just opposite, worked great. Used one layer of 1" mdf on that one and had no issues. Same window brace also. I'd use birch if I had to do it all over again though and probably do flush mount double baffle. Maybe add some 45s in the corners.

Edited October 5, 201212 yr by reelfish92

I've heard of people using birch instead of mdf, just don't know the benefits. I'll try and search that (but the search on this site seems jacked up).