Need help on wedge box air space please.

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I Am An Idiot said:
Assuming you are using 3/4 inch material and according to Perry's calculator the box has an internal volume of 1.846 Cubic feet


I was trying to teach him to excersize that grey lump in his scull.

Far to many easy questions being asked.
5 minutes of research would have given him all the info he needed.

Oh well.
 
Re: Hey Mad

skooter said:
thanks for the support. not really a computor person or much on sterios either, just trying something new instead of building Harleys and drag cars for a change. but hey, Thanks

Yes, speeeeling haz know boundrys.

Computer
Stereo's

Sadly basic maths seems to be a comodity used by geeks (me), and rocket scientists that nobody can understand.

I like to (when I can be bothered) give helpfull prods in the right direction.
Sometimes there is nobody around to help, that's when the basic's can help.

No, I'm not perfect, not by a long shot.
But hopefully I manage to do more help than harm.

Skooter, if you need the exact internal volume, don't forget to subtract the volume of the drivers, ports, and anything else in the box.

Just out of morbid curiosity, roughly how old are you ?
Sadly, I've hit 'the top of the hill'.
At least for me it's all down hill now :D
 
I know this thread is for air space for a wedge box but does anyone know what the dimensions of a rectangular Dual 12" sealed enclosure would be for 1.25 cu ft. of air space? I might think about building my own or adding in some wood to my current box to make the air space better. I tried using:

http://www.bcae1.com/spboxnew2.htm

To try and calculate dimensions but the closest I could get it to was 1.28 cu ft. I'm looking for L X W X H dimensions if using 3/4 MDF board. Thanks :cool:
 
To try and calculate dimensions but the closest I could get it to was 1.28 cu ft. I'm looking for L X W X H dimensions if using 3/4 MDF board.

That's only .03 ft (51 cubic inches), which is about 1% off. Keep in mind published spec's aren't that accurate for production woofers. It's not unusual for woofers to be off 10% or more.

To calculate the volume, just average the top and bottom length (depth). Then use that in the L x W x H to find the total volume.

Tim
 
Yeah, that's not telling me much :cannotbe:

I just need to know the dimensions of a box with maybe a little bit more that 1.25 cu ft cause of the displacement of the sub...like 1.28 cub ft would put me right on the nose of 1.25 with my 0.035 sub displacement. So, maybe measurements for a rectangular box for 1.28 or 1.30 cub ft..What would they be?

Like for example a box that is 14" H 16" W and 33" L..What cubic ft is that? I need to know the measurements of a box that will have the cu ft I need...
 
Flyin11 asked:

Like for example a box that is 14" H 16" W and 33" L..What cubic ft is that? QUOTE]

One step at a time:

1)Assume 14 x 16 x 33 is what you plan to build.

2) If you use 3/4" wood, then subtract 3/4" twice from each measurement to get inside dimensions of that box. That leaves:
12.5 x 14.5 x 31.5

3) For a rectangular box, multiply L x W x H:

12.5 x 14.5 x 31.5 = 5709 cubic inches

4) To change that to cubic feet, divide it by 1728:

5709 / 1728 = 3.3 cubic feet,

which is 1.65 cubic feet per woofer


To work it from the other direction and design a box of a certain volume:

I just need to know the dimensions of a box with maybe a little bit more that 1.25 cu ft cause of the displacement of the sub...like 1.28 cub ft would put me right on the nose of 1.25 with my 0.035 sub displacement. So, maybe measurements for a rectangular box for 1.28 or 1.30 cub ft..What would they be?

Let's say 1.28 cubic feet is the target. There are 1728 cubic inches in a cubic foot, so you're looking for:

1.28 x 1728 = 2212 cubic inches, that's inside volume.

Volume of a rectangular box = Length x width x height,

so start by dividing your 2212 by one of these dimensions, then by another, and the result will be the third.

Let's say you want the face of the box to be 13 inches to accomodate a 12" woofer and a little room to spare. So:

2212 / 13 = 170

If you have two woofers, then you'll need at least 25" of width, so lets use that:

170 / 25 = 6.8 (round it to 6.75" or 7" to make cutting easier)

So that will be 13 x 25 x 7 inches inside measurements.

If you're using 3/4" wood, add 3/4" twice to each measurement.

Therefore, outside dimensions will be 14.5 x 26.5 x 8.5


Tim
 
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