What is the formula to calculate the cone area of a subwoofer?

 

anyone??

 

Why do you need this?

 

I know this won't be exact but what I was going to figure out of what multiples of smaller woofers would give you the same cone area of larger woofers. I know you can not calculate the exact db you will hit but I wanted to play around with some figures.

I was thinking about useing 4 jlaudio 6w0 in my FC I wanted to know if they would have the same cone area and potentially move the same amount of air as say 1 12

 

Cone area is just the area of a circle. Typically cone area is measured from the middle of the cone surround.

Area of a circle = pi(r*2)

So measure the diameter of the cone, and divide that by 2. Then multiply the result by two. Then multiply that result by 3.14

8" area=50.24
10" area=78.5 square inches
12" area=113.04 square inches

This is what everyone uses. Technically it is imperfect because the area of a circle is for a flat surface and the cone is concave. To be perfect you would need to compute the volume of a frustum. The formula above if fine for your use though.

 

Fuzzy math.

 

To get beyond fuzzy math you need 2-d calc or 3-d calc. Want to learn?

If you want the short cut then go to JL's website and lookup the specs for each sub. The parameter you are interested in is Sd-cone area. Oh yeah, remember Xmax has a big impact on SPL as well so don't under value it either.

 

2*pi*r = the circumference....

pi*r^2 = area...

so take the diameter.... divide it by two.... square that and multiply by pi (3.1415...) but like they said before it won't be totally accurate

 

Thanks for the info!!