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SilverSquared
02-17-2008, 02:04 AM
I have 4 CVX 12s. For the box area, I have 57 wide, 14 tall, and 17 deep, MAXIMUM. Thats 1.95 cu.ft. per chamber. I was reading the manual, and it says...

"Vented Compact, minimum enclosure volume"
1.75 cu.ft. + port displacement
2.25" x 12.5" port, 20" long


who can do it? Challenge from hell for me, because INSIDE the cab, I have 49" I can cut. Inside the bed, i have 57", So its gotta bevel inwards somehow.:crying::crazy:

revrider1
02-17-2008, 02:05 AM
I wanna follow this one, im very curious?

Mr Cabinetry
02-17-2008, 01:30 PM
I wanna follow this one, im very curious?

OK, so what's the max working width 49" or 57"???? And what is this " bevel " you are referring to that the enclosure needs to fit.

Also, what type of vehicle are we talking about here, pic's would be helpful to get a look at the install area.

Next, what model year CVR 12's, if your willing to provide the physical dimensions of the subwoofers will go a long way in how the subwoofer will be fitted within the design.

I'm always up for a challenge when it comes to what will vs what can be done.


Phil
Woodlawn Cabinetry

SilverSquared
02-17-2008, 08:25 PM
the opening of the back wall of the cab can only be 49" wide. Inside the bed is 57" wide. SO...the box can be 57" wide, but the 4-12s can only be 49" total. Its going in the bed of a single cab mazda truck. The subs are not CVRs, they are CVXs.

Nominal Impedance: Dual 4-Ohm
Resonance Frequency: Hz 26.4
Power Handling Peak: 1500 Watts
Power Handling RMS: 750 Watts
Total Q-Factor: 0.36
Equivalent Volume: 2.3 ft3
Outer Frame Diameter:12-9/16"
Hole Cut-Out Diameter: 11 1/8"
Mounting Depth: 6-5/8"

IDSkoT
02-18-2008, 02:48 AM
What about an I shaped design?

Or you can make a T design, with the bottom going into your cab. The thing is, the bed and the cab move seperate from each other, so, you have to make something to attach it to the cab instead of the bed. Unless your truck is unibody, which I'm not sure of. What you could do is make a T shaped box, and then attach it to the back of your cab and make the hole you cut out of your bed slightly larger so you give it enough moving room.

Mr Cabinetry
02-18-2008, 05:54 PM
OK, I got it now. The intent of the design for the enclosure is fit in the bed of the truck with a cut thru into the cab which the cut thru is 49" width.

First problem off the bat is the kicker spec's since they are stating 1.75 cu.ft net per subwoofer, so that already puts you at 7.0 cu.ft before you add to that subwoofer, port, port wall displacements.

So, that will mean more room for the design of the enclosure and as someone stated a " T-Shape enclosure " is the only way to make up for the volume thats needed, but, instead of bring the " T " into the cab, put the " T " between the fender wells in the bed of the truck.

By putting the " t" between the fend wells will free up design area for the front baffle and porting considerations.

What is the width between the fender well in the bed of the truck???

SilverSquared
02-18-2008, 09:26 PM
I want to avoid going in between the wheel tubs, as much as possible. I can go back, but not far. My frame rail and axle will eventually raise up into the center of the bed. I think in between is 46" and I can go back6 to 8 inches, BUT...If I massage the wheel tubs when I get to that point, I may be able to get a little wider than 46 and deeper than 8 inches.

Mr Cabinetry
02-19-2008, 11:22 AM
I want to avoid going in between the wheel tubs, as much as possible. I can go back, but not far. My frame rail and axle will eventually raise up into the center of the bed. I think in between is 46" and I can go back6 to 8 inches, BUT...If I massage the wheel tubs when I get to that point, I may be able to get a little wider than 46 and deeper than 8 inches.

OK, if I took what you gave up so far for the enclosure given what I've already done for the design the enclosure right now is at 7.56 cu.ft. - Not including the sub and other displacements.

And since your going to be " tubbing out " the bed of the truck and you don't know at this point what you will or will not have to work with dimensions wise

The best course to take is finish all the metal work in the bed of the truck and then design the enclosure to fit around that because given what the design of what the enclosure requires when all said and done, your looking at close to 8.0 cu.ft. total for the enclosure.

But the real pain in the azz of the whole design is trying to fit 4 12" subs with ports with a 49" width x 14" height and trying to do it without wasting a sh!tload of area to do it to make it all fit.

I'm just going to show what talking about purely from a concept perspective:
http://i29.photobucket.com/albums/c251/MrCabinetry/Various%20Pics/4cvx12sporteddraft.jpg

Looking at the front baffle area given for the width working with, the subs would have to angled as such to fit them all and for the minimal angle to be used not to eat up volume and still fit the subs.

Porting wise, best that can be done here is use 6 - 4" dia ports which is 75 sq.in. of port area. For the tuning Kicker spec's given the volume of the enclosure cal's out to 44 hz port tuning.

Those 6 - 4" dia ports would be 10" long.

The only thing unknown is the power, but, if each sub got 750 watts with those ports, there is no port noise.

SilverSquared
02-19-2008, 05:51 PM
THAT would be Perfect. I love the way that looks. That's ideally what I was considering, but with the 2 center subs straight, but that would cause the face to be further back, and the 2 angled subs to be more steep, so then the depth would be GREATLY reduced.

Mr Cabinetry
02-19-2008, 08:42 PM
THAT would be Perfect. I love the way that looks. That's ideally what I was considering, but with the 2 center subs straight, but that would cause the face to be further back, and the 2 angled subs to be more steep, so then the depth would be GREATLY reduced.

Yes, correct. The outside subs would have to be at a much greater angle to allow for the two inner subs on the flat panel to be much wider to fit the subs and the ports and deeper back into the enclosure. That would also reduce the volume even more, thus would require the volume difference to be had by increasing the enclosure size some where else in the design.

With the above design, all that needs to be done is gain another .50 cu.ft. and it's a done deal.

Phil
Woodlawn Cabinetry

SilverSquared
02-22-2008, 02:53 AM
what if we went back another 2"? Think that would compensate?

Mr Cabinetry
02-22-2008, 09:19 AM
what if we went back another 2"? Think that would compensate?

If the center portion was increased from 8" to 10", that would solve the volume issue. Actually, it would give the design 8.48 cu.ft., more than enough when factored in any bracing displacement added to the enclosure.