Hey y'all i need help with makeing a box for an xterra. It would be for 2 10" susb(alumipro). the box he has is way to small for the subs and look horrible. I am going to use particle board but about what dimensions should it be and what should the angle of the front board be. I was thinking about 15 degrees from center(reference point) or 75 degrees from the ground (reference point).i am going to place the box inbetween the wheel wells directly behind the back seat.

 

Well, first, you need to know what the internal dimensions have to be as required by Alumipro. Then you need to find out how wide the space is between the wheel wells to determine the width, and figure out how tall they can be according to the hight of the back seat, or how tall you want the box to be. Then we can give you a bit more help...........

 

The first step you should take is some measurements. You also will need a calculator. Find the recommended box size from the manufacturer, and then multiply cubic feet by 1728. This is going to give you the volume of the box in cubic inches. Then divide your total by the width between the wheel wells in the truck. Then divide by the height, and you will be left with the depth. A quick example would be.....
2 cubic foot box (for both subs)
3456 cubic inches needed (internal dimensions)
If the measurement across was 37 1/2, you could only use 36 for your measurement if you use 3/4 inch thick wood. 3456/36 = 96, then you measure the height that you need, say 13 1/2 which will equal 12 internal. 96/12 = 8 so you internal depth will be 8 making the box 9 1/2 deep externally.
37 1/2 X 13 1/2 X 9 1/2 external dimensions. you can then cange the angle by making them all right angle triangles to find the change of volume. If you want to keep it simple, just make the bottom panel 2 inches longer, and the top 2 inches shorter. That will give you an angle, and not change the volume of the box. You should use some bracing, and lots of liquid nails. If this is your first box, keep it simple. For all the pros that want to tell you every little detail to follow, don't worry about it this time. Just build a good sealed box. I hope this helps.

 

There is alot of freeware out on the net you can use to make the calculations MUCh easier. Boxplot, WinISP are two.

 

i suggest you use MDF instead of particle board. yes it's more expensive but it'll last longer in the long run.

 

1. Particle board sucks.
2. You need exact specifications from the manufacturer to tell you how much airspace is required.
3. Why do you need angles?

 

do all home depot stores have MDF? i tried looking for it today and they only seemed to have particle board

 

Yes, all Home Depots should carry MDF. It's about $18 for a gigantic sheet.

 

enough to build 2-3 boxes out of?

 

One, maybe two depending on size. Most likely one though.

 

i found the specs for the speakers. Here they are
Description

Description

Impedance = 4 , RMS/Peak = 300/600
Fs = 23 Hz , Qms = 2.60, Qes = 0.27, Qts = 0.25,
Re = 4.0 Ohms, Vas = 2.8 Ft3, Xmax = 12 mm,

They are 2 10" subs. the specs i came up with for the box are as follows. They appear to be for both speakers but that cant be right.

13.031496=height ( how tall it is in the trunk
19.80= length ( from wheel well to wheel well)
8.50=depth
I this for one or two speakers. i think it is for one but whatever. I can just double it

 

I realize this is repetitive, but whatever you do, don't use particle board, tried to do that once, the sound was absolutely horrible!!

 

I still need this last bit of help

 

What is your question?

 

I usually angle the front 15-20 degrees and the back the same, like a trapazoid not a parallelogram. This will help break up any standing waves. You want to avoid building a cube. It is also good to have the width and hieght vary by about 30%.

MDF is the really fine grain particle board as opposed to the stuff with big a$$ wood chips in it. You can never use too much liquid nails!!

 

thank you very much