I am the guy that installed that stack. We are using the upper Everest's as the woofer section of the WTMW array. So, we are "only" using 6 of the 28BSSt2. The crossover is active, and DSP is used to do the time delays and various eq's to get the speakers to act sound as one unit. I do the fine tuning using a number of acoustic recordings and just tune for flavor and texture to the clients taste.
Elizabeth, you are right, there is a massive sub panel around the corner with an industrial/lab grade toroid in it. The cable feeding everything is 4ga wire, with the 12 ga tapped off for the receptacles. System is kept balanced throughout.
There is a wonderful effect with this stack of speakers; the use of the upper woofers with the bottom ones provides active cancellation of the room mode at 18 to 26 hz. So, one can go up and down in volume and the room doesn't load up. The upper woofer is shut off at 300 hz; its just for the bass and sound staging. The upper woofer also provides varying levels of cancellation of other room modes, which simplifies the eq solution (the simpler, the better).
With these amps, the Speaker stack does extremely fast attack and great decay on bass. The mid-range is very focused, with tons of layering and, of course, micro and macro dynamics. It's quite fun to play big band and other dynamic music. Blues recordings are just...shocking.
Steve, the JBL spec on the bass is in open air; in a room you usually have to turn the 20 hz DOWN as with room gain you actually end up having too much.
There is a rug, with a heavy felt underneath, that is rolled up for this picture, that occupies the space in front of the listener.
