Port Displacement

[HotCarl 10+ year member]

im doin a box for a 15'' L7. using 4 inch aeroports, tuned @ 32 hz.

i need to know the formula to figure out how many cubic feet the port displaces.

can somebody post it for me?

thanks

Jordan.

Click to read more...

 

[PowerNaudio 10+ year member]

The formula for figuring displacement of a vent is as follows:

Vent Displacement = (1/2 the outside diameter X 2) X 3.14 X length of

the vent

For example, a 4" port, 5" long would figure like this: (a typical 4" port

has an outside diameter of 4.5"): 2.25 X 2.25 X 3.14 X 5.0 = 78.46

cubic inches of displacement!

here is a link to an exelent tutorial. LINK