I am going to build (or have built) a 1.88 cuft enclosure tuned to 32hz for a 12" Fi BL. i want to put a round port in the box. Can anyone tell me the dimensions of the port? I know there are tons of calculators out there but i don't know how to take in acount port noise and all that fun stuff. I don't know whether to put one port or multiple or anything. Thanks in advance!