Well....way back in 1976, when I was doing my final A Level Engineering science I was working on the design of loudspeaker enclosures and the aperiodic design came up from my research into the 1960s designs of Dynaco and their A-25 system. There had also been an article by Edward Jordan, later of Jordan Watts fame, in an ancient Wireless world, belonging to Mr Jepson, our teacher. It was from 1956 or 57, I think. The maths in this was pretty scary as he was using electrical AC theory stuff to electrically simulate various speaker enclosure aspects including something for a Goodmans Axiom something or other, can’t remember the model.
I looked at at the size of a Dynaco, and the plans for a DIY leaky box, using Goodmans drivers and found that the ratio of vent area to cabinet volume appeared to be roughly 8 sq in per cubic foot.
I’ve seen 10 sq in per cubic foot somewhere else, and decided to go down the middle, for no scientific reason, so I ended up with 27 sq in of vent area for my 3 cu ft cabs.
Sorry I can’t be any more helpful. I didn’t develop the aperiodic research any further for the A level as I had to pare down the sprawling project to get it handed in to the examiners. It all seems to be an empirical process even today. There don’t seem to be any hard and fast rules.
However the 9sq in vent area per cubic foot of cabinet seems to work very nicely.
Scott may have the Jordan article but it was very technical and scared the 18 year old crap out of me. For my two penn’orth, there’s no need to get that OCD. The 9 sq in per cubic foot ratio seems perfectly adequate.