So I have two 21" dp's and I am wondering, what is a good rule of thumb for port area on a spl box? As far as square inches per cubic ft? I have never done a spl setup. And I am planing on doing two slot ports for spl and plugging one for daily use. And would 10 square inches per cube too small for daily beating? Also may try something like four areos to keep down on internal space.

A guy on here broke a few records with a ridiculous amount of port area just with two tens. I think if you have about 20-24 sqinch per cube tuned reasonably high maybe 37-39 Hz it'll do well.. but this is only my option.. I don't have very much experience with SPL. So we'll see what everyone else has to say about my info

I've often read 12 to 16 sq ft of port area per cubic feet.

Edited May 10, 201015 yr by Notorious from Martinique

I've often read 12 to 16 sq ft of port area per cubic feet.

Thats a typical rule of thumb.

there is no rule of thumb for spl.

IT's all about about how much LENGTH you have available to get the right tuning with what port area u can fit.

Do NOT use port calculators when tuning for spl as they will not help.

If u can fit 600sqin with the right length then go for it.

If the port needs to be longer than physically capable, then u gotta start plugging parts of the port up to decrease port area.