Building a box for subs

[SkiIIz]

Anyone know what kind of wood needs to be used and how much it costs? Also need some carpet. Crutchfield wants $20 for a 9x3' sheet. Anyone know of any places cheaper? I have a single 15" audiobahn flame sub. The only spec I can find on it is volume inside the box and the size of the hole. Anyone else have a single 15" sub box they could give me measurements off of? Thanks

SkiIIz

Silver 97 bird: CAI, B&M Shift+, !Cat, Fan mod

[naptown]

You could just buy a box from Steve at Subthump he builds boxes just for our fbodies!

[TrixTeR]

I, like you SkiIIz, also just bought subs recently and i was planning on building the box after the weather warms up a bit.

First off, it is ALOT cheaper to build your own then to spend 300 dollars for someone else to do it.

to answer your question, they are generally made of 3/4th inch particle board (cheap) or MDF (not as cheap). You can use other types of wood if'd you like but it won't sound as good.

all you need is the recommended volume for the driver, from there you can build your box however you want, just as long as the volume is close to the recommended one.

Also, i bought my carpet/terminal from crutchfield.. i don't know if it was the best buy or not but i just got it when i was buying the rest of my stuff.

[naptown]

Single 15'' wbs15 2.0 cu.ft vinyl & carpet $250 quoted from subthump.com

[RSFireDog]

Use MDF, not particle board. Particle board has too much vibration. As far as carpet goes, you can prety much go anywhere to get it. I got mine from GM and it wasnt too expensive.

You should be able to pull optimum enclosure size off the specs for the sub..

[Red96CamaroRS]

i build sub boxes for all the little rice boys at my college. Basic things you need are MDF board, caulk, 1/2'' screws, carpet, and a nice saw to cut the circle out. its not that hard-

talk to steve at subthump.com first, hes the man when it comes to f-body boxes.

[DrMilhouse]

Of course I'd say buy one from Steve too, but if you're not going to do that, then what you'll need is what was mentioned above.

3/4 MDF (don't use particle board - yes there is a definite difference), you'll need some caulk to seal the box, some screws and glue to keep it together and of course some tools to cut everything out. The price you were quoted for carpet is really not too bad. You can probably get ahold of it locally from an uphulstory/furniture repair shop. Probably cost you about the same, but you'll be able to see what you're getting before you buy it. You'll also need some really good spray on glue of some sort to glue that carpet on to the box.

HTh

[zlexiss]

MDF, Epoxy resin, and Cab-o-sil for the most solid construction :)

[TrixTeR]

while we are on the subject, anyone know why most subbox companies use a divider to split a box in half/thirds (using 2/3 subs).

I thought without the divider you get like a +3db sensitivity.

is there another reason they put a divider in besides to maintain box strength?

[SkiIIz]

Alright I got 4'X8' sheet of MDF for $13. I'm going to just get capret wherever I can find something cheap that I like. I also got some glue, calk, and screws. Alright the only measurements I have are a 13 3/4" hole for the sub, the sub is 8" long, and the volume is 2 c ft. I have noclue at how to design the box to give me the volume.Does anyone have a single 15" sub box with around 2 c ft volume? Anyone know a website or progman for computing it? Thanks for all the help.

[96firebird311]

A great box building program can be downloaded from here. Download WinISD Pro. (make sure you get the pro version) It's pretty user friendly compared to many other programs. If you need help with it, just ask. [img]smile.gif[/img]

You've already bought everything you need to make a quality box, no need to look any further. I can talk you through each step if you like. To calculate the volume of a box, you use Length x Width x Height. Use inches. Then take your total and divide by 1728. This will give you your volume in cubic feet.
Example:
Your box is 20" X 15" X 10"
So......
20x15x10=3,000
then....
3000/1728= 1.7361111111
Your box has a volume of 1.7361111 cubic feet.

So figure out how much air your woofer is going to need. (You said 2cuft. right?) So, on paper, draw out a box with some measurements that will fit it your hatch. Figure up the numbers and see where you stand. Don't forget to account for woofer displacement inside the box AND take into account the thickness of the wood. If you are trying to figure the volume for a box that isin't a rectangle, try to "break" it into several smaller pieces and figure it out. Remember, a triangle is half a square! [img]tongue.gif[/img] ;) If the box is so irregular that this is not possible, fill it with something like sand or packing peanuts. And then empty them into a 1cuft. cardboard box. That should give you a good idea of what you are working with. For more accurate results, line the box with trash bags and fill it with water. Gallon by gallon. Then go here and convert gallons into cubic feet! :D Works great!!!!! :D :D :D

[SkiIIz]

OK this is what i think Im gonna do. Im gonna cut a piece 15" x 30" for the bottom. The where the sub is there will be one 17" x 30". The one on the backside will be about 14" x 30" and then one about 5" x 30" for the top. Then I plan to lay it down on the 14"x 30" and the sub will face like right up at the glass up on that upper trunk part right behind the seat. Id really like to keep the t glass holders there. Is this a bad idea to face it right at the glass? Any better suggestions? And if my calculations are right that'll be about 1.6 cu. ft. Is that right?

[DrMilhouse]

You got a sheet of MDF for $13? Where? What thickness is it?

[96firebird311]

That sounds about right. For 1/2" atleast.

[pvtschultz]

I always used at least 3/4" or 1", but I was never worried about weight or cost. If you are using more than one sub, divide the box into equal portions for each sub, and seal the divider. It will add rigidity to the box for better sound and keeps the subs from trying to push the other giving you better sound. I used to get my carpeting at Menards, same stuff as Crutchfield, lot cheaper. I have used both sealed and ported boxes. For our cars, I would stick with sealed. When your subs are pounding, you will be "sitting in the box", meaning there is nothing separating the subs from you but air. In cars with non-folding back seats where you can't get into the trunk, I have found larger ported boxes help to carry the sound and hide the sloppiness of a ported box. Also, IMO, I would mount the subs pointing towards the floor of the truck with like a 2 or 3 inch gap between the face of the subs and the floor. Then I would leave open place in the box that would connect the floor of the where the subs are facing and the rest of the car. By doing so, you would have a combination of both ported and not. I would have the subs in 2 sealed boxes facing down with like 3 or 4 inches in the middle between the subs. Then seal off the rest around the truck well so the sound and the air moves through the "port". Mounting subs facing the rear of a car produces more bass inside the car.