View Full Version : Oh crap . . . Port question

04-20-2006, 05:55 PM
Do I subtract the port volume from my boxes net volume?!

My box is 31.5" x 14.5" x 18.5" (internal dimensions) = 4.89 cubes

My port is 14.5" x 3" x 14.75"

So my box is 4.7 cubes after displacement tuned to 35hz right? Just making sure.

04-20-2006, 06:53 PM
Net Volume=Vb
Vb + port Displacement + driver displacment + any other objects that displace air=gross volume.

So you take your 4.89 cubes as your gross, subtract port displacement (.35ft^3) and your driver displacment to get your Net volume.

04-20-2006, 07:17 PM
i get just under 34htz.

you have to take the effective port length into account. 14.75 + 1.5(half the width of the port) =16.25 as your effective port length.

04-20-2006, 07:39 PM
and you have to account for that port wall so the width to find displacment is 3.75" and the depth is shortened by .75" because of the front baffle...i forgot that earlier..