I have some prior experience with this type of speaker configuration, where the enclosures containing the mids and highs were in one pair of cabinets, and the woofers were in another pair of cabinets. All were tall line driver configurations, and essentially produced sound from just above the floor to some moderate distance from the ceiling (from memory, ceiling height was at least 9'). This system was located in a fairly large, but certainly not cavernous, room. This room featured a shallow bay window in the wall behind the speakers, and single entry / exit doors on both side walls, but at the very rear of the room. The listening sofa was approximately 3.5' - 4 ' from the rear wall.
In that room the speaker system in question certainly loomed large, but nonetheless gave excellent results. There were definitely constraints on placement for any of the speaker cabinets.
The woofer towers wound up roughly 2' behind the mid-highs enclosures, and shifted roughly 2' closer to the side walls.
This is the type of placement I'd try first, if your room allows it. There are good arguments for placing the woofer towers asymmetrically, but my slightly OCD side likes the symmetry. I'd first prioritize the distance between the mid-highs enclosures for best response in the room, and also for soundstaging, then work on final position of the bass towers.
The size / volume of the room, distance of the prime listening seat to the mid-high towers, and how much space is then available to the sides and rear walls, will be a factor in positioning of the woofers. It's possible that no two rooms, or differing listener preferences, will arrive at the same placements.
This is a round-about way of saying what James said above more succinctly. Can you tell I've been giving this some thought since the Bass Towers were announced?
