subwoofer box dimensions needed

Hey everyone,

I was wondering if someone could give me measurements for a 3/4" MDF Sealed Box for 2 12" Kicker Comp VRs. I dont have a program to make one

HEre are the specs

Model:

Nominal Impedance [Zn], ohm [per coil]              2 or 4

Resonance Frequency [fs], Hz                            26.1

Power Handling Watts, Peak (RMS)                  800 (400)

Effective Excursion [EXmax™], in (mm)             .498 (12.64)

DC Resistance [Re], ohm [coils in series]            6.99

Mechanical Q-Factor [Qms]                                9.99

Electrical Q-Factor [Qes]                                    .556

Total Q-Factor [Qts]                                           .527

Equivalent Volume [Vas], ft3 (L)                      3.37 (95.37)

Net Displacement, in3 (cc)                            122.1 (2001)

Outer Frame Diameter, in (cm)                        12 1/2 (31.7)

Hole Cut-Out Diameter, in (cm)                         11 1/8 (28.3)

Mounting Depth, in (cm)                                   6 5/16 (16.1)

Minimum enclosure volume is 1 ft^3

Maximum enclosure volume is 4.6 FT^3

Sure.  Measurements are inside:  W 20.5"  D 33.5"  H 12.6"  Total 5 cu ft.  Brace it down the center between the woofers...you can use a solid baffle if you want to.

YEs i believe u are right. Can u make the box a little bit wider and taller than more depth

THANKS!!!!!!!

Alright, here's some more to pick from.  I'm still using 5 cu ft because I've looked at this sub before and thought (if you have that much room for it) it would be good (for two, of course!)  You can always cut dimensions down a little bit if you need to...remember, there is A LOT of play for designing a sealed box for this particular sub.  You can tell that by the manufacturer's description of anything "above 1 cu ft but not more than 4.6 cu ft" per sub.

W 23.4  D 24  H 15.4

W 21.5  D 21  H 19

W 22.8  D 22.4  H 17

W 24.8  D 24.3  H 14.3

W 23.7  D 26  H 14

Did you look at that volume calculator?  You can do this too.  If you want to leave the baffle thickness out of it altogether and just calculate inside volume, put a zero in the thickness box.

Also, keep in mind how  you are going to build in the bracing.  This box will certainly need at least one full-size interior baffle, and it should be front-to-back between the driver cutouts.  You can cut a large hole out of the baffle so that the box is all one interior volume, or you can use a solid baffle so that each sub has its own air space...same either way (I'd opt for the solid bracing baffle).  The face baffle gets the most pounding and is the weakest one of them all because of the cutouts.  And for a box this size, I'd use other bracing inside as well.  Here's an example:

With a sealed box of this size, you don't really need to get too particular about measuring each piece of baffle material you use (takes up air space and is counted as "displacement").  Just skootch up the measurements of each dimension a little to make up for the displacement of bracing, drivers and baffle walls.  Like, a 22" W should become a 24", etc., which takes these material thicknesses into consideration.

Take good advice when you get it, racerx22.  Bracing isn't mentioned just because I like to type a lot of words...

1.  Measure the space in your car to see what maximum size can be.

2.  Add thickness of material X number of panels to the dimensions of that proposed box.  See if this new bigger size fits the space.

3.  Draw a sketch of the box.  It doesn't have to be pretty.  Show all dimensions, inside and outside.

4.  Now break it down to a rectangular sketch of each panel.  Figure out how you are going to construct the box so that you know how the panels (baffles) will connect.  Draw plenty of little diagrams.  You will arrive at how big you need each panel to be.

Now is the time for you to get busy with paper and pencil and figure out your cut plans.  Use the dimensions of a 49" X 97" sheet of MDF and go to work.  Allow extra space for saw kerf, which is the waste caused by cutting.  This is where you are on your own.

EDIT to add:  When I gave you those measurements I seemed to forget that there were two 12" subs for the width.  Try out one of these wider boxes:

W 25.8  D 22  H 15.25

W 26.6  D 21.6  H 15

W 27.3  D 21.4  H 14.8

W 28  D 22  H 14

ok.... Its going into a trail blazer. The dimensions of the trailblaze are

Width 46" inches

Height  20.5" Inches

depth 31" inches  ----dont wanna use that much

The dimensions you gave include the wood thickness?

No.  W 28 X D 22 X H 14 would be just inside space.  With 3/4" MDF and one middle divider baffle, the overall outside dimensions would be W 30.25 X D 23.5 X H 15.5

Read the sticky above about how to build a sub box.  If you had tried out that easy-to-use calculator that I told you about with any of these dimensions, you would have seen that they all come out to 5 cu ft.  And if you know that 5 cu ft is your target for inside volume, you would also know that the dimensions couldn't possibly include the walls.

You should have learned enough about this part of the build to use the calculator yourself and arrive at a suitable box size for your vehicle.

(...ok, I double-checked this post...)

W 30.25 X D 23.5 X H 15.5 is overall box size, correct?

It depends on how you want to construct your box.  The thickness of the MDF is going to have to be taken into account.  If you make a full size top and bottom, those panels would be 30.25 X 23.5  That's the full width and depth of the box.

If that's the case, then the vertical panels will be shortened by the thicknesses of two layers of MDF (the top and bottom panels).  Instead of being H 15.5, the actual panel would be H 14.  Front and back, side and side all would have a 14" height.

If you want the front and back panels to overlap over the edge of the side panels, they would be full box width, meeting the corners of the top/bottom panels.  W 30.25

If that's the case, then the side panels width  would be lessened by the thicknesses of these two overlapping front and back panels.  Take 1.5" off the box depth to get the panel size.  That would be 22".  The inside divider panel will be cut the same as the side panels.

2 pieces:  30.25 X 23.5  (top and bottom)

2 pieces:  30.25 X 14  (front and back)

3 pieces:  22 X 14  (side and side and middle divider)

Draw out a cut plan on a sheet of MDF if you want to be able to talk them into cutting these out for you.  You have somebody to cut the holes too?  ;)

Any braces inside that bad boy?

I would.  I would use a baffle on each side, halfway back from the face.  Large hole cut in the center, like this:

They have to fit snug, so at this stage of the construction getting them into place could be troublesome.

If you don't have the material to cut a full baffle for each side, you could do it another way.  Again, on each side halfway back but using scrap pieces of material, something like this:

You would have a rock solid enclosure that will give you all the SPL these subs will put out.  The box won't be stealing any of it away with flexing.

Nice job so far.  She's looking more attractive all the time.