I'm looking to learn about Air Motion Transformer technology

Thanx Mike I would love to. You wouldn't happen to have any dealers in New England?
Right now I use a TACT 2.2x for my front end which is more like The Trinnov Amethyst which is an ST2 with a few more inputs and a volume control. The room correction is identical. If my TACT were to fail that is what I would get at this moment in time.
I had a close relationship with Radomir Bozevic the DSP wizard behind  TACT. Do yourself a favor and do not sell anyone the microphone. Have your dealers set up the system, show the customer the basic stuff and remove the Mic. Boz got buried in phone calls. People were getting entirely lost in his program and coming up with inferior results which gave him a bad name aside from driving him crazy. His mistake was that he was direct purchase only and did not have any dealers to rescue the customer.
Anyway, stacking the woofers would be expensive. They would have to go all the way from the floor to the ceiling to create a line source that would go down to 20 Hz and match the output of the towers. You could take 4 subs and spread them across the front wall into the corners and achieve the same results. You have a horizontal line source! I do this with my ESLs with great results. No mater where you are the sound balance remains the same. Now my ESLs will not go as loud as your towers. Right now I use 4 12" subs. I would think 8 10" drivers would do the trick up to reasonable levels. To do  vertical line sources you would have to stack 6 or seven subs on each side? If you were to put them right into corners you might have output to match the towers which is academic really as nobody in their right mind would play it that loud.
Mike

And I would think Arion would know as he makes both types of speakers.
Having owned Apogee Divas I can relate to ribbons. His Analysis Audio speakers are strangely reminiscent of Apogee speakers. Mike, is there any connection to Apogee? I know, Apogee used a quasi ribbon woofer and it appears your speakers are using a design more like Magnepan. Ribbons are not just aluminum foil but aluminum foil traces laminated to a plastic. I think Apogee used very thin Kapton but I am not totally sure. The traces are connected in series which raises the impedance to somewhat reasonable levels. The impedance curve is extremely flat so in realty ribbons are a very easy load for an amp that can tolerate lower impedance's. Magnets run down both sides of the ribbon. A ribbon 6 feet long is very floppy so even though it is firmly connected at it's ends there are usually foam blocks placed at intervals to support the ribbon. You can not tension the ribbon too high or you will damage it. 
The Apogee bass ribbon was very easy to damage so I think the use of a planar magnetic design is smart. It is a much tougher driver. 

Arion, I just came from your web site and I really like a lot of what you are doing. Using the Trinnov for bass management duties is brilliant. I would never use an analog crossover in this position. Crossing at 120 Hz is also great. I cross at 125 Hz from ESL line source speakers to subs. IMHO people tend to cross too low were there are a lot of room problems which makes integration difficult. What I would like to see is Apollo 14's supplied with 4 sub woofers. The Apollo 12 is not quite tall enough to act as a line source down to 100 Hz where it still probably has significant output. So, as you move away from the speaker the mid bass will fall off. Two subs can only act as a point source so the low bass will also drop off as you move away from the speakers. You would need at least 4 sub woofers to create a linear array and balance the output.
With that efficiency rating you should be able to replicate a jet aircraft with 100 watts! I would love to hear them.

Mike

Mike, I did not catch who you work for. Dayton??

Mike

An air motion transformer is like an accordion. It has a pleated diaphragm that squeezes air out of the pleats when it vibrates so very little vibration will produce a lot of air motion. Just another way of matching impedance with air. They are easy to make as tweeters and will go down lower than most dome tweeters. Some of them run as low as 500 Hz. They will also go very loud. It is much harder to make a woofer with this technology but I think people are working on it. If you go to Parts Express you can see that there are many of them for sale and most are cheap. They have also been around since the 70's. My experience with them is very limited. The high end speaker industry has mostly avoided them for some reason preferring dome tweeters.