2245H (Double) Enclosure suggestions needed

[loach71]

I have read Greg Timber's article on this forum about a JBL 2245H in a 12 cu ft. tuned port enclosure. This looks VERY interesting. I have four 2245H drivers, and I want to make two enclosures that support two each of these drivers. I am thinking of simply making enclosures that are like two of the Timbers' enclosures stacked one on top of each other.

I will be using these enclosures as subs, crossed over at 80Hz, with an equal component Sallen & Key filter topology with a 4th order rolloff. I have two BGW 750D power amps (oldies but goldies) to power the subs.

Any suggestions would be greatly appreciated.