For those of you with a thing for cutting mdf to be different........
http:/wanderkolonie.org/speakers/dbb2.gif
This design doesn't give the hight of the box but going by other horn designs and forums speaker diameter plus 2" appears to be right for the internal hight, giving an external hight of 21.5" using 3/4 mdf. Also going by other forums using speaker diameter plus 2" works for any other size driver. So why not 10s,12s or 15s.
Just in case you are tempted by this box please note............ I have never built, heard or seen this box so have NO idea that.......... 1.this is the best box in the entire world. 2.this is better than ported,sealed...blar,blar,blar,blar. 3.this will work with alpne type r's 4.this will work with JL audio whatevers 5.this will get you more female attention. 6.this will make up for you lacking in other departments. 7.whatever other questions somebody is bound to ask.
What it will give is the abillity to proclaim.... "YEAH, BUT YOU HAVEN'T GOT A HORNLOADED PORTED BANDPASS SUB HAVE YOU?"
Sorry forgot to point out that the port shown isn't round but a slot port going from top to bottom of box. This looks like it's tuned to about 40hz so if you are changing speaker size the port length will need changing too. I'm not sure wether the slot port is important to performance or not. If not then it might be best to switch to a round port so it will be easier to adjust tuning once the box is built. also check out.....