hey guys, im currently building a custom box to put a single 12 under one of the back seats, i have the box "mold" built (cardboard and duct tape) which i will be fiberglassing soon, i had a couple of question dont know if anyone could help.

1. Any ideas on how to measure volume of the box? it is one of the most random shapes i have ever seen.

2. In terms of making a ported box, how big of a port should i have, where should it be on the box, and how long should it extend into the box..?

i have posted pics of what i have made so far. sorry for the quality i took them with a phone which blows..


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yo its looking good. im not real sure about the building of them...im pretty sure pirata made his I THINK. one thing though..some subs dont need ports..some NEED to be inclosed..does yours need a port?

 

length X width X height equals volume

This should get you close enough! Does the company that you got the speaker from give you the option for a sealed box?? If not I would just get some 1 1/2 abs pipe from Home Depot (they sell it in 24" sections) and cut me a piece long enough to get you about 2" off the bottom of the box!

 

The best measurement you will probably get is a guess. Dust off your old geometry books and break the shape down into smaller shapes like cubes and pyramid shapes. You won't be exact, but you can get close enough for calculations.

 

the sub i have is a 12 inch sony xplod, not sure of the model #.

box specs are 0.83 cubic feet for ported
1.15 feet for sealed.

you say break out the geometry tooks lol you should see the shapes this box is, i'll try to take some better pics tomorrow, but if you were to look under the seats of your ram this box is bascially the EXACT shape of the hole. at the front where the fold down leveler thing was it extends up 2 inches he the seat, and lowers to 1 inch as it goes back, like i said this is the most messed up shape i have ever seen! lol...

 

You should be fine with a sealed box!!

Trust me, I know what the shape of a custom made box is like!



Mine is sealed

 

do you have any other pics of your box being made? what is it made of fiberglass mdf? or what? any other details would be helpful the way i have laid mine out was just my way of thinking, but im also open to any other ideas!

 

For the bottom of the box, you can lay something acrossed the carpet that can take the heat of hot/warm fiberglass. then you can take some hot/warm fiberglass and start molding your box! I had a heat gun with me that helped the fiberglass get hot and then it would cool off fast and take shape of the funky whole! Then you can mold the fiberglass over the template you have and then you can remove the template once it has hardened! Just remember if it is not the prettiest, you can cover it with carpet and it looks like it was done by a pro! Once it has cooled they you can pull the box out and take the ??? that you has seperating the fiberglass from the carpet! You can run you wires under the carpet and drill a small hole in the box (and silicone around the wires) and run the wires to the speaker.

 

Since you're fiberglassing it, after you got it all done couldn't you fill it with water and find out how much water it'll hold then find the area of the box using that information. Just be sure to let it dry before use, right. Just a thought.

 

that is a good idea, i have thought of doing that but the issue is i want the box to be to the sub specs. If i complete the box first and then measure volume it means modifying thebox yet again to meet the subwoofer's specifications.