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kfx450r
05-02-2009, 09:20 PM
This box is for 2x 15" Fi SSD's i want it to slam. Going to be pushing atleast 800watts to each sub.

Box is as follows:
9.15 cu ft after sub displacement but before port.
Wedge box 48" wide, 26" tall, 20" bottom depth, 12" top depth.
4x 3" diameter pvc tubing cut to tune to 35 hz. which will be mounted at the top of the box coming to 130 cu inches of port area.
http://i129.photobucket.com/albums/p232/yx230/P1010173.jpg

kfx450r
05-02-2009, 11:09 PM
Heres my first google sketchup attempt. This is how i plan for it to look.
http://i129.photobucket.com/albums/p232/yx230/box.jpg

thegreatestpenn
05-02-2009, 11:11 PM
you need WAY more port area. try 4" ports at least instead of 3"ers

kfx450r
05-02-2009, 11:16 PM
you need WAY more port area. try 4" ports at least instead of 3"ers

scratch

mazdakid
05-02-2009, 11:25 PM
4 3" ports is nowhere near 130" of port area
4 6" ports wouldnt even be that much

kfx450r
05-02-2009, 11:27 PM
4 3" ports is nowhere near 130" of port area

how do i accuratly calculate port area with pvc

dappa5
05-02-2009, 11:53 PM
what is this thing going in?

kfx450r
05-02-2009, 11:57 PM
what is this thing going in?


ext. cab colorado truck. What if I did a slot port 19" wide, 6" deep and 9" into the box for 35hz. would that be enuff port area. I dunno how to calculate t i just did length times height came to like 170. Calculator says for these 2 i need 150 ish port area
http://i129.photobucket.com/albums/p232/yx230/untitled-3.jpg

dappa5
05-03-2009, 12:07 AM
slot port will do you right and usualy it's 12-16 in sq per cu ft so hats you total cubes?

kfx450r
05-03-2009, 12:09 AM
slot port will do you right and usualy it's 12-16 in sq per cu ft so hats you total cubes?

the box is 9.15 cubes counting the subs displacement but not the port displacement. Fi says 3.5-4 for each ported so i shuld be good even after port displacement

Guess i need a little less port if its 12-16 cuz 170 would be 18. 18"x6" port that goes 8.39" into the box would be 151 sq inches i think? at 35 hz.

dappa5
05-03-2009, 12:21 AM
tht is still to big you only need 12-16sq in per cube so 9.15 x 16 =54.9 sq in tht box is massive i 'd try 6x 12(72 in sq) using the rear wall as rear of port (to cut down on displacement) adjust length to appropriate freq

kfx450r
05-03-2009, 12:45 AM
tht is still to big you only need 12-16sq in per cube so 9.15 x 16 =54.9 sq in tht box is massive i 'd try 6x 12(72 in sq) using the rear wall as rear of port (to cut down on displacement) adjust length to appropriate freq

9.15 x 16 is like 146

dappa5
05-03-2009, 01:06 AM
srry
meant try 9x 18

mazdakid
05-03-2009, 11:57 AM
your 19x6 port would be 114" of port area.

93dakota
05-03-2009, 12:33 PM
how are you calculating the port length. If i got the right numbers with the port being tuned to 35hz and having a port of 18x6 your port would need to be closer to 17 inches not 8.

dappa5
05-03-2009, 03:40 PM
your'e right i was just giving him port area not length guessed he could do that on his own:D

kfx450r
05-04-2009, 02:53 PM
Do you put in volume of box after displacement of the driver[s] AND the port tubes or just with the driver. Becuz if i put in say 9 cubes with the driver..the length of porting is diff than if I put in say 8.8 cubes becuz of port displacement.

siucsaluki11
05-04-2009, 03:21 PM
the box is 9.15 cubes counting the subs displacement but not the port displacement. Fi says 3.5-4 for each ported so i shuld be good even after port displacement

Guess i need a little less port if its 12-16 cuz 170 would be 18. 18"x6" port that goes 8.39" into the box would be 151 sq inches i think? at 35 hz.

18*6=108. Area is 2 dimensions, volume is 3. Quit thinking and guessing your numbers and just select the calculator app on your comp and plug numers in. Its not that hard.

mlstrass
05-04-2009, 03:40 PM
use NET volume to determine port length/tuning. So you need to subtract subs, port, and any bracing that will be inside the box to determine the net size...