Any inherent problems with this enclosure design?

[joe carrow]

Yeah, that's right, they are additive. That's how active 4th order (24db/oct) crossovers work- they're just a 2nd order cascaded into another 2nd order.

 

[Lothar34]

I wouldn't count on it. A slot port that's 1.25" thick probably wouldn't obstruct the flow too badly if it only has one bend in it. How about a compromise, and do 1.5 or 1.75?

Some forum and google searches for "slot port" should help you find some good rules of thumb for how narrow you can make it, as well as bends and rounding. Good luck!

I did a search and found several references to JL Audio's port tutorial:
http://mobile.jlaudio.com/support_pages.php?page_id=165

According to them, a slot port should have less than a 9:1 height to width ratio, mine is 3.4:1, so I think I'll be OK there.

When I turn off the end correction in Unibox, it changes the port length from 29.9" to 32.2". I'm pretty confident in my ability to measure the effective length of the port path, so I think I'll go by that number.