So a slot port is slanted on a baffle, say the port is 6.5" longer at the bottom than the top. Is the tune calculated from the bottom, middle, top, or all three? Technically, shouldn't it perform as 3 tunings, say to within 2 Hz of eachother (bottom/middle/top)? Would that mess with the response?
What determines tuning? We can have vents of any shape without changing the function... Tubular, rectangular, triangular, pentagonal vents all have length and _ _ _ _?
_____ | I | O | ----|----- | /\ | / \ | ---------------------
_ _ _ _ = area? But in this case Port Length is not a constant, more a function of height in the sense that the port is longer at the bottom than at the top.
Honestly I would use something between the middle and the top as the actual length, but this is what intuition tells me, I don't speak from experience.
Oh... I'd use the middle personally. Let us know what frequency the cone uses the least throw at when you're done eh. That will be the resulting resonant frequency of the air mass.