Well I've been reading through the forms was inspired to start on a sono tube project. So I got the sonosub calculator and started playing some numbers and decided to get a 24 inch diameter tube 12 feet long and cut it in half for 6 foot per sub I guess. I thought The effective volume ment the total volume until I got the tube home cut it in half set it in place and just kept shaking my head saying to myself How in the world could this tube only be 7 1/2 cubic feet. So then I'd punched the numbers in a volume calculator and got over 18 ft.³:raped: so now I'm realizing there's two different figures, volume and effective volume . Could somebody shed some light on this confusing situation.

Does this sound like way too much volume for a 15? Here are some speaker parameters
3.95 ohm
Qts: 0.578
Qes: 0.673
Qms: 4.095
Fs: 24.5hz
mms: 130g
cms: .300mm/N
BL: 11
Vas: 284L
xmas 27 mm