No cabinet is the best cabinet. But that's only one reason why I prefer planars---ESL's, magnetic-planars, ribbons. All but one pair of speaker "cabinets" I do have are actually open baffle frames; the fact that they aren't sealed and are heavily braced reduces the ability of the walls to resonate.
The one pair of sealed cabinets I do have contain subwoofer drivers. I made the enclosure as a box-within-a-box, with a 1/2 space between the two, the cavity filled with no.60 Silica sand. The interior box is cross-braced every 5", and that plus the damping sand results in very "quiet" enclosures.
