it there a formual for figuring it out?

 

http://www.the12volt.com/caraudio/boxcalcs.asp

Head right to the bottom... among other caculators.

Mark

 

alright so the volume of the port is the same as what it displaces in the box?

 

no it will displace more than it's volume, because of the wall thickness. Not much, but more


Mark

 

ok, im only using white sewer pipe its only has a very thin wall

 

oh ok, then it's relatively insignifican't then...


Mark

 

making a abc box for 2 15's trying to keep it as tight as possible on the volumes, its a gona be a big box, 9 cubes,

 

the only reason why I mentioned it, is because if you, or anyone was using 0.25" PVC or something similarly thick, then on a 3" x 16" pipe, the difference in using the interior volume, opposed to the actualy displacement would be about 0.1-0.2 of a cubic foot... Which could add up if you had multiple ports, or wanted the exact Net volume of the box...

regards, Mark