How much port area for two DC XL 15's?

[Decaf]

sd*xmax=vd

also taking into consideration power because the sub will be near xmax on more notes if you have more power

why can you get away with less than ideal port area? because out of the entire range of notes the sub plays there might be only 5-10hz notes near xmax and the rest are much lower in displacement, thus you wont need as much port.

[Traks]

sd*xmax=vd

also taking into consideration power because the sub will be near xmax on more notes if you have more power

why can you get away with less than ideal port area? because out of the entire range of notes the sub plays there might be only 5-10hz notes near xmax and the rest are much lower in displacement, thus you wont need as much port.

Best way put ^^^

I ran 2 xls in 6 cubes last year with almost 21" per foot. And still think I could have went bigger. But it was tuned for numbers 1st. Daily second and worked out it was musical.Threw another set of subs in the same box on the same power and that was an epic fail. Lost 4db on the meter but was still very musical. Boxes should be built for the sub....not just built and then a sub tossed in.