Box design advice

[qwilkins]

Im building a new box,but this is my first time actually trying to build a ported box i need some feedback on the design.

The design via google sketchup: https://www.dropbox.com/s/n6vqtito0gxoi0j/36Hz.skp

If i did it right the box should be tuned to 36 Hz and have 7.844 ft^3.

thanks in advance.

forgot to mention im using 2 l7 15's

[hdorre]

Why not use 1 port?

[qwilkins]

Why not use 1 port?

I wanted to have the individually ported to see the difference between common chambered and separated ported boxes

[Joe X]

Your calculations look wrong. If I got your dimensions right 16 3/4 x 45 1/2 x 20 3/4" you have about 3 cubes of net airspace for each sub which is too low for them, it's at least more like 4 cubes net each what will work nice with those.

[qwilkins]

Your calculations look wrong. If I got your dimensions right 16 3/4 x 45 1/2 x 20 3/4" you have about 3 cubes of net airspace for each sub which is too low for them, it's at least more like 4 cubes net each what will work nice with those.

Ok so, if i add 5 more inches to the width making it 50.5 should have about 5, but then with the space the wood is taking up i should have a little of 4 left over right?

[Joe X]

Going 50 1/2W, would up it to about 3.4 cubes net per sub from nearly 3 cubes, still a long way to go.

[qwilkins]

Going 50 1/2W, would up it to about 3.4 cubes net per sub from nearly 3 cubes, still a long way to go.

Can only go up to 55 in length 20 dept 17 height. That's the max i can fit in my trunk. so 16.75 X 54 X 19.25 wouldn't work either? sorry i forgot that you have to use a different formula to calculate air space for ported boxes .

[Joe X]

17x54x20.75 would figure to 8 cubes net @ 36Hz, to keep tuning to 36Hz port area would need to be kind of low, it will work ok but may not be very efficient if you go all out on power.