Re: (Probably Stupid) Thiele-Small Specification Question
You might want to consider learning a bit more before designing/building your own enclosure if this has you tripped up. But the net volume is after sub/bracing/port displacements are subtracted. The gross volume is prior to displacements being subtracted. Every manufacturer's recommendation that I've ever seen is a net volume. And, generally, the manufacturer is recommending the smallest possible size. Most subs like much more than the recommended. And, fyi, this is not a t/s question.... I was directed to the pro designers on this site after attempting this myself when I knew nothing about the subject. They were right to do it, so I'll do the same. Hit up a pro, man.
CDT carbon fiber 6.5" mids & DD T2 tweeters on a Polk Audio PA D4000.4
SP4 15 w/ Tantric SHD softies on a DC 5.0k
2 runs Monster Cable 1/0, SounDrive rca's, Singer 310a 6 phase, Exide G78 under hood XSD3100 rear, plenty of deadener