i'm planning on running 2 orion hcca 12's and the box i'm planning on housing them in aimed at 30hz. it's dimensions are 39" wide, 14.5" in height, and 32" in depth. my port measures 13" wide, 8" in height, and 27 3/4" in depth. will these measurements yeild my 30hz goal. i'm not that good with measuring volume and everything so a little assistance will be greatly appreciated.

Try using thing http://reaudio.com/speaker_box/LPort_Box_Calc.html

Plug in your dims and then monkey around with the port till you get around 30hz

my winISD says that you need a port 56" long. That will yield you a 4.8 cubic foot net box after the 3.56 cubes that the port displaces and .25 cubes for the two subs. Your box is 8.6 cubes gross.

hmm, the RE calculator is quite a bit off from my calculations. I'll have to check.

The differences lie in that the RE calculator doesn't take two things into account, one being sub displacement, and the other being the thickness of the wood used as the port wall. It assumes zero for sub displacement and that the port wall is also zero. However, sub displacement, as I figured, was .25 cubes, and the port wall also displaces about .25 cube using 3/4" wood.

thx alot fellas. KU40, these are the calculations i've gotton my poking around on the calculator on the12volt website. i thought that they were pretty much in range but i guess not. i calculated my box volume on this site http://www.the12volt.com/caraudio/boxcalcs.asp and my port volume on this site http://www.hometheatershack.com/forums/enc...ume-calculator/. guess they're not all that accurate as is winISD. well what dimensions would i need for the optimum enclosure for a ported 30 hz box for those 2 subs?

unless you're talking about a side port that also stretches across the back of the box as well.