Without giving it much thought, I've always assumed that Vas is directly proportional to Sd or surface area of the driver cone. Not!-

Vas = po*c^2*Cas

where

po= air density

c = speed of sound

Cas = acoustic compliance of driver suspension

I don't see Sd in that equation.

Another equation that I ran across is

Vas = (1.4 X 10^5)*Cms*Sd^2

but that is the same thing as

Cms = Cas/ Sd^2

So the equation is saying that Vas is directly proportional to the compliance of the driver's suspension (spider and surround) no matter what diameter size the driver is.

Am I missing something or is this something that isn't generally understood?

Sorry if you are more interested in the practical side, but I think that some of you like to discuss this kind of thing, at least I hope so.

-Pete

Vas = po*c^2*Cas

where

po= air density

c = speed of sound

Cas = acoustic compliance of driver suspension

I don't see Sd in that equation.

Another equation that I ran across is

Vas = (1.4 X 10^5)*Cms*Sd^2

but that is the same thing as

Cms = Cas/ Sd^2

So the equation is saying that Vas is directly proportional to the compliance of the driver's suspension (spider and surround) no matter what diameter size the driver is.

Am I missing something or is this something that isn't generally understood?

Sorry if you are more interested in the practical side, but I think that some of you like to discuss this kind of thing, at least I hope so.

-Pete

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