I am looking at having a cabinet maker make a pair of enclosures for the 604E. They will be about the size of the Stonehedge (9 ft3) but in an art deco style similar to the 605 or 607. I have quite a bit of Altec literature and have the graph that reflects resonance frequency, enclosure size and port size but I am not sure if it is still relevant. Given the enclosure is 9 ft3 and the resonance frequency is 27.10 what size port should be used?

Second anyone try the Iconic DN604E-16U crossover?