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sniper007
02-03-2007, 02:28 PM
Can someone tell me how much cubes im working with with these measurements? Also if possible the cut of wood im going to do. Ok here goes nothing. Im going to illustrate it cuz i dont know how to write it out. This box is for 2 12"s btw.

http://img.photobucket.com/albums/v481/sniperior/newboxdesign.jpg

http://img.photobucket.com/albums/v481/sniperior/sjkghjksds22222.jpg

http://img.photobucket.com/albums/v481/sniperior/BOTTOMVIEW.jpg

http://img.photobucket.com/albums/v481/sniperior/TOPVIEW.jpg

Does this make sense or do i have some mistakes?

Oh **** i forgot that the height is 14" sorry bout that.

sniper007
02-03-2007, 02:38 PM
bump

sniper007
02-03-2007, 02:42 PM
bump

sniper007
02-03-2007, 02:53 PM
sum1?

sniper007
02-03-2007, 03:09 PM
http://img.photobucket.com/albums/v481/sniperior/sjkghjksds22222.jpg

http://img.photobucket.com/albums/v481/sniperior/BOTTOMVIEW.jpg

http://img.photobucket.com/albums/v481/sniperior/TOPVIEW.jpg

Hope this makes things a little more clearer.

sniper007
02-03-2007, 03:14 PM
bump

mlstrass
02-03-2007, 03:16 PM
Use the calculators here. Calculate one side x2 + the middle hump part.

http://www.the12volt.com/caraudio/boxcalcs.asp#wed2

sniper007
02-03-2007, 03:20 PM
im not good with those calcs have no idea what im doing with them!

sniper007
02-03-2007, 03:23 PM
bump

sniper007
02-03-2007, 03:27 PM
bump!!!!

dinty01
02-03-2007, 03:29 PM
hey, if I got it right, youll be around 4.39 square feet without port and sub displacement. I broke the box up into 3 parts, the 2 outside sections are the same dimensions, and then did the center as a 3rd box. for the 2 outside boxes it would 23x10x14 = 1.86 cubic feet per side, so 3.73 cuft for both sides, and then for the inside it is 6.75x12x14 = 0.66 cuft, total is 4.39 cuft. And if youre wondering where the 10 came from, the way I was taught it is easier to make the front of the box a square, so you take the top and bottom depths, add then together then divide by 2, in this case 8" and 12" added together get 20, divided by get 10", I then did this for the center box as well, with a dimension of 6.75" straight up and down, some will say this method is incorrect but its worked for me several times without problems. If you try using those dimensions I posted above, you should be able to use a box calculator to double check my math, I think its right if I understand your drawings. If you have any questions feel free to post them, Hope this helps----Dinty

sniper007
02-03-2007, 03:32 PM
i think its 2.36 cubes but not sure, are u suppose to add 8 + 12 to make the depth? cuz the depth is 8 by 12.

sniper007
02-03-2007, 03:36 PM
hey, if I got it right, youll be around 4.39 square feet without port and sub displacement. I broke the box up into 3 parts, the 2 outside sections are the same dimensions, and then did the center as a 3rd box. for the 2 outside boxes it would 23x10x14 = 1.86 cubic feet per side, so 3.73 cuft for both sides, and then for the inside it is 6.75x12x14 = 0.66 cuft, total is 4.39 cuft. And if youre wondering where the 10 came from, the way I was taught it is easier to make the front of the box a square, so you take the top and bottom depths, add then together then divide by 2, in this case 8" and 12" added together get 20, divided by get 10", I then did this for the center box as well, with a dimension of 6.75" straight up and down, some will say this method is incorrect but its worked for me several times without problems. If you try using those dimensions I posted above, you should be able to use a box calculator to double check my math, I think its right if I understand your drawings.

im not using any ports cuz its sealed. how does sub displacement work? 2 12's are going into this enclosure.

dinty01
02-03-2007, 03:51 PM
i think its 2.36 cubes but not sure, are u suppose to add 8 + 12 to make the depth? cuz the depth is 8 by 12.

well, you add those 2 numbers then divide by 2 to get the depth, you do this so that(in theory) the front of the box would be straight, not a slant so it is easier to calculate the internal cuft of the box. For the center section I added the 8"(bottom) and 5.5 "(top) to get 13.50", then divided that by 2 to get 6.75" deep, then multiplis 6.75x12x14 and got 1134, then divide that number by 1728(use this number when calculating internal volume in cubic feet) and got 0.66 cuft, then added that to the 3.73 cu ft to get 4.39 cubic feet internal volume(this is the gross internal volume in cubic feet).


The sub displacement is how much volume the woofer takes up inside the box when it inside the box. With your woofer there should be a spec sheet(if not you can probably find the specs online) and there will be a displacement figure for each woofer(and it is usually in cubic feet already so no need to recalculate it), you then subtract that number from the gross internal volume to get your actual volume inside the box in cubic feet. If you have 2 woofers then add the displacement twice then subtract that number from the gross volume figure. I dont know what woofers you are using but if you have a spec sheet and find the displacement post it here and Ill show you how to do it if you want----Dinty


BTW if I am wrong with these figures please feel free to correct me, Im no master fabricator, just going by my personal experience.