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anyone have any links to programs that i can use to calculate box sizes? i also need one that can figure port size realated to freq. tuning. im getting ready to replace my sub, and also have to build a custom enclosure for my boy's civic, and i need a program that can accurately calculate the internal air space, then how much it has with the port, and what size and relation to the box the port needs to be to get the freq's we are wanting. thanks.

 
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http://www.linearteam.dk/
there's Winisd, it's not really what you are looking for though. You input the T/S parameters for your specific sub, and it'll give you a port size/internal volume for a certain tunign frequency.

You seem to want somethign to calculate the volume in a box. just multiply the internal length, width and height. Then, subtract the driver displacement and subtract Portlength*pi*r^2. It's pretty straight forward. remember to conver to cubic feet if your measurements are in cubic inches.

 
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thats where my problem is, there aren't 4 euqal sizes, its gonna be an odd shaped box, thats why i was wondering if there was a program somewhere. if it were a standars square box, then i could do that, but with the odd shape, it'll be kind of tough.

 
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thats where you break out piece of paper and figure it out on your own. htis is where high school geometry comes into play

or

you could use an autocad type of device

 
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where could i dl an autocad program (which one really), i slept a LOT in geometry. the teacher passed me cause she liked me as a person i think...

 
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oh, if you know nothing about cad now, itll take you a few months to design only that box.

it cant get any simpler than doing it by hand. i do ll my boxes with paper and a calculator anyways...

wht kind dimensions are you lookin at?

 
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not sure yet, still deciding on which woofer to get, it'll either be a JL 13.5w7 or 12W7, so once that is decided i can figure a little easier. as for the other box, the guy, for some reason is wanting a pyramid shaped box with the top flat instead of pointed. and he wants it to be glassed to the floor, the actual enclosure will be mdf (where the airspace is), but he does want it glassed in once it is built. he has 2 fosgate HX2 12's, and the punch 1200 amp. why he is spending so much money on a box with those woofers and amp is beyond me, but hey, i just build what they want right? im still trying to figure the airspace on that one, and where to port it at. i haven't looked at the info on the woofer yet, im still designing it, as far as shape, and whether to let them share airspace or split it. he didn't specify if he wanted it ported or not, so i may go sealed yet. thats why im having a difficult time, cause its an odd shape.

 
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i have worked with a cad program before, but its been about 4-5 years (since my sophmore year in highschool)

 
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a square pyramid or a triangle one?

Either way, i think the forumla is V = (1/3)*(area of base)*(Height)

If he wants the top flat, just think of it as a smaller pyramid inside a larger one, and subtract.

 
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For your own design with the W7's, you don't need to calculate woofer displacement, JL already accounts for that in their recomended box sizes.

 
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ok, i think i have the basic design done for the pyramid shaped enclosure. now onto my box, im pretty positive im getting a single 13.5w7, now i gotta figure out how im gonna enclose it, and where. i am thinking about a couple of options. 1. build enclosure that faces into cabin, fiberglassed into area where rear seats fold down. amps remain in spare well, glassed in. 2. glass amp rack into behind rear seat area, build sub enclosure that uses spare well, and comes up out of it, facing rear of car (spare well part being where the port would snake under the box). 3. same as # 2 but facing into cabin. 4. some other design using different layout. i can't decide which way to go with this. and was wondering your opinions, as far as aesthetics, acoustic qualities, sq qualities, and spl qualities. what would you all reccommend?

 
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