ports

I did a search but didnt come up with the answer to my question.

Some subs give you dimensions for a round port.  Can I do a slot port or square port instead?If so how would I go about the math to make sure I get the measurements right so it doesnt mess up the sound?Im not giving certain brands or sizes because its kind of just a general question about math.ORIs there a place where once I decide what sub I am using and look up a slot port size per that sub and enclosure size?Im just asking because some compaines give you a square inch area X a length and some just give you a diameter X length.Ive built about a dozen or so sealed boxes but havent done any ported because I didnt want to get it wrong, well I am ready to learn about ports and the correct way to incorperate them into the enclosures so any help would be greatAny links would also be greatThanksBernie

Bernie

MECP Certified

64 Impala Wagon

2007 Camry LE