horn calculations

[jellyfish420 10+ year member]

i've been searching all over for a couple formulas maybe someone could help me. i'm looking for the formula for throat area and compresion chamber area. i've searched all over and everytime i find them...there is just a big d@mn X where the formula should be.

here is a link to where i found the fomulas, or where the formulas should be...

http://www.melhuish.org/audio/horndesign.html

Click to read more...

 

[pwnt by pat 10+ year member]

Throat area:

At=(2(pi)*Fs*Qts*Vas)/c

At is the area of the throat (m2)

FS is the nominal air resonance of the driver

QTS is the total Q of the driver (note, some formulas use QES, the electrical Q here - Bruce Edgar for one)

VAS is the equivalent volume suspension (m3)

c is the speed of sound (344 m/s)

Compression chamber:

Vb=Vas/Fc/(Fs*Qts)

VB is the back volume (volume of compression chamber next to horn throat, the front chamber in the diagram on the previous page)

Vas, Fs, and Qts are standard driver parameters

Fc is the lower cutoff frequency of the horn flare (I think)

 

[jellyfish420 10+ year member]

on the compression chamber volume...what unit of measure is that in? meters^3, feet^3, liters, what?

 

[JimJ 5,000+ posts]

Meters squared, because he's using Vas in that value.

 

[pwnt by pat 10+ year member]

That's actually directly from that site. The only thing that isn't showing up for you is the equations, which I listed because they showed up for me. Don't ask me how to apply them, I have no idea... heh.

 

[jellyfish420 10+ year member]

ya i can get every thing but the equations. thanks!

thanks jack...i'm doing a little bit of experaminting //content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif

 

[pwnt by pat 10+ year member]

From what it looks like, I think the result is in liters...