Yes, i'm running mine sealed. The ft3 is approx. .8. Didn't build the box, bought the two as a package. JL recommends. anywhere between .5 and 1 ft3 for the 10" so i'm somewhere in the middle. The sub handles mega power well. Happy with it over all, but if i would have had to pay the high normal retail price here in Canada, i would have went with a Elemental A.

 

I think if i was going to play around with the box a bit i would try a ported enclosure. I've never heard a w6 ported but i'm sure it would sound great. JL has a good design on their site, but w/ 2 12"'s it might be a little big.