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## Main Question or Discussion Point

Hello all, first post here to physics forums and I have a lot to learn. I will be attending a northern Ontario university for Mechanical Engineering in fall so hopefully this relationship proves fruitful.

Here is my problem, I bought a new stereo for my jeep.. and I am having trouble designing a closed baffle enclosure for my 10.1'' subwoofer.

Here is where I am and how I got there, and why I am having trouble...

Given:

Fs = resonant frequency = 33.5 Hz

Cms = mechanical compliance = 0.0002m/N (metres / Newton)

Sd = effective area of cone = 0.0415m^2 (metres squared)

Unknown:

Cas = Acoustic Driver Compliance Cas=Cms*Sd^2

Cab = Acoustic Box Compliance Cab=Cas *R\

R= driver to box compliance ratio

R = 2

So: Cas = 0.0002m*(0.0415m^2)^2

=0.0002m/N*(0.00172225m^4)

Cas = 3.4 * 10 ^-7 m^5/N

Therefore Cab = 3.4 * 10 ^-7 m^5/N divided by two

= 1.72 x 10^-7m5/N

Now Volume of the Box Vb = Cab *Gamma Constant (Lets assume it is 5.77)

Vb = 1.72 x 10^-7 m^5 /N * 5,77

Vb = approx .99 x 10^-7m5/N

^^^^NOW HERE IS MY ISSUE^^^^

How the hell am I coming up with such a wrong answer, surly area is not expressed in terms of M^5/Newton and why is my volume so high? The Manufacturer recommends an enclosure from 0.08 m^2

please HELP, I will greatly appreciate it and contribute as much as I can to this forum :)

Also I am fresh out of high school took a year off, and its been 2 years since high level Math or Physics courses so please excuse me if the mistake I am making is pity.

Here is my problem, I bought a new stereo for my jeep.. and I am having trouble designing a closed baffle enclosure for my 10.1'' subwoofer.

Here is where I am and how I got there, and why I am having trouble...

Given:

Fs = resonant frequency = 33.5 Hz

Cms = mechanical compliance = 0.0002m/N (metres / Newton)

Sd = effective area of cone = 0.0415m^2 (metres squared)

Unknown:

Cas = Acoustic Driver Compliance Cas=Cms*Sd^2

Cab = Acoustic Box Compliance Cab=Cas *R\

R= driver to box compliance ratio

R = 2

So: Cas = 0.0002m*(0.0415m^2)^2

=0.0002m/N*(0.00172225m^4)

Cas = 3.4 * 10 ^-7 m^5/N

Therefore Cab = 3.4 * 10 ^-7 m^5/N divided by two

= 1.72 x 10^-7m5/N

Now Volume of the Box Vb = Cab *Gamma Constant (Lets assume it is 5.77)

Vb = 1.72 x 10^-7 m^5 /N * 5,77

Vb = approx .99 x 10^-7m5/N

^^^^NOW HERE IS MY ISSUE^^^^

How the hell am I coming up with such a wrong answer, surly area is not expressed in terms of M^5/Newton and why is my volume so high? The Manufacturer recommends an enclosure from 0.08 m^2

please HELP, I will greatly appreciate it and contribute as much as I can to this forum :)

Also I am fresh out of high school took a year off, and its been 2 years since high level Math or Physics courses so please excuse me if the mistake I am making is pity.