Box Design Help

[anubis]

i just got news of my fiance getting a me an 88 plymouth wagon and i need to know how much volume i need for 4 ma audio 150xe 15"s and the length of the four 6" aeroports.

i would like to tune around 30Hz and and crx style

[andym85]

i would guess around 3cubes/sub, so about 12cubes net...i tried finding specs but couldnt, and for some reason their site wont load all of the way for me...but each port would have to be around 20"+ to get you down to 30hz or so

[Dale]

I would do more like 4-5 cubes per 15" sub.

[andym85]

well at 4.7 cubes/sub each port would need to be like 13" or so for a tuning of 30hz

[anubis]

well at 4.7 cubes/sub each port would need to be like 13" or so for a tuning of 30hz

do i have to add the displacement of the ports with the 4.7 cubes or is it included?

[andym85]

i was just throwing around some rough numbers and i came up with 18.8cubes net (which accounted for taking out displacement for subs/ports)..so if you shoot for around 18-19cubes net then that should be pretty close...oh yea, four 6" ports 13"long displace about .85 cubes

[doughboi916]

how do you calculate displacement for the sub and ports?

[andym85]

pi*r^2*length, then just multiply that by the number of ports and divide that by 1728 and ya got it...same as any other shape really...area * length = volume

[andym85]

oh...and the sub displacement is usually given to you in the specs..

[anubis]

oh...and the sub displacement is usually given to you in the specs..

thanks for the info and help i appreciate it