What is the "design" of the "ULTIMATE" loudspeaker

Very tough question... I cannot answer.

Monster speakers...

Rockport Xenia's 4 Cabinets at 500 lbs average each.

"Clearly, the horn loaded planar transducer system absolutely stands alone with regard to its ability to resolve low level detail, micro-dynamic shadings, maintain a cohesive harmonic envelope, and render complex musical textures. Of course, its most important attribute is a uncanny ability to convey musical emotion and the artist's very intent. Couple this with its ability to be driven by even a 10 watt triode with dynamic headroom to burn and you begin to get a feel for this loudspeaker's uniqueness."

HORN SPECIFICATIONS: Dimensions: 25 1/2" wide x 82 1/2" high x 36 3/4" deep Weight: approximately 550 lbs. each horn recommended minimum amplifier power – 10 watts nominal impedance - 4.9 ohms, purely resistive

WOOFER SPECIFICATIONS: Woofer Tower Dimensions: 21 1/2" wide x 82 1/2" high x 36 3/4" deep Weight: approximately 450 lbs. each tower recommended minimum amplifier power - 50 watts nominal impedance - 8 ohms

$128,500

Kharma Grand Enigma: "This 12 ton system is fully active with 30kW of amplification, equipped with 24 ultrahigh efficiency planar-magnetic HF-units, 24 15-inch LF drivers and 48 6-inch MF drivers. Placed in a specially prepared subterranean listening room of 45,000 cubic feet, it presents sound with incredible dynamics and limitless power, easily reproducing live concert levels at a distance of 10 meters."

$1,000,000 ?

Wilson Audio WAMM's: $225,000

of the speaker systems listed by jtinn, i've listened only to the wamm's. i've also listened to the avalon sentinels several times. at $85k (usa msrp), they may be a bargain. they're certainly the most beautiful "big" system i've ever seen; the veneering is incredible, book matched on 22 facets/surfaces. and they weigh only 1/2 ton with supplied sub amps. oh, BTW, they sound really good, too! -cfb

Maybe the better question would be, "are the huge ultimate speaker systems mentioned really that much more convincing than the best $20k-$30k systems?"

I think the ultimate system would only have two drivers. A woofer and a tweeter. I beleive multiple drivers create to much phase distortion with is timeing errors because of the varying distances of the individual drivers from your ears.

For the same reason the ultimate speaker would have the tweeter in the center of the woofer. Of course with current technology this creates its own problems.

In my opinion,

The less complicated, the better. My favorite are the Magnepan 3 ways (3.3R, 3.5R, 3.6R). When you go to a 4 way or more driver scheme, the crossover is more difficult & expensive to implement. Speakers are just like power amps,
more drivers (& more output transistors) no matter how closely matched to a tolerance, are going to still deviate from each other more than less drivers & less output transistors.
A classic example of this philosophy are the Sound Lab speakers & the Martin Logan CLS - just one big diaphragm & no multi way crossover. Another example are the audiophiles who swear by two-way monitors, they can image fantastically when set up well.
I myself prefer the Magnepan because of that 6' tall ribbon. It is very detailed, yet forgiving.
I've personally heard the WAMMs & MAXes, for high SPL rock they are impressive-they can drive you from the room. I just find them too fatiguing to listen to for very long.