Sealed or Ported? Fi Q

"Ported box we recommend using 6-10 cubic feet @ 28hz tuning, you can tune a little higher if you wish but we recommend keeping it under 32hz. Again the same 12-16 square inches of volume applies per cubic foot of volume."

I don't think 2.3 cubes with a 4 inch round port is going to cut it.

 

For the Q15...



As you can see, I have .07342 ft3 leftover that I'd like to fill up with bracing. I'd prefer to use MDF or wood over threaded rods, but how do you guys think I should brace this box? A strip of MDF on each side of the sub?

Also, could one of you check my port length for me? I used an online calculator and it said 29.5" long for a 2.75"x20.5" port, so I went with a 30" length. I'm going for 32Hz.

 

What the ****. WinISD beta is telling me 27.85" and the online calculator is telling me 29.52"

 

Yeah I mean I can probably get 5 cubes sealed with the 18. It's just I don't know if it's worth it. The Q15 ported might be louder.

 

Yeah but one 6" port? That's 28.27 sq. inches of port... they recommend 12-16 per cubic foot... and a minimum of 6 cubes. We're not meeting any of the criteria with the 18 ported.

 

Those are my max dimensions if I'm going to keep the spare tire... 39" wide, 14" deep, and 22" tall... which is 5.56 cubes before sub, port, and brace displacement.

 

I know, and what I'm saying is, 5something cubes ported with only 28 square inches of port isn't enough. I need at least 6 cubes and at least 72 sq. inches of port. I can't fit an 18 ported.