The top model is an all open baffle line source using the same drivers.
There is a front and rear baffle. In between the two baffles is a wedge shaped panel that faces the front drivers. This panel will also be foam coated with No Rez. This panel will deflect and absorb some of the rear wave of the front panel drivers and keep them from directly reflecting off of the servo subs on the rear panel.
I think the rest is pretty self explanatory from the pics.
Yes, these will not be cheap, but then again, what will top them?
Deals will also be made on the first run. Big deals!
There may also be a version made with all digital crossovers using a true top level DAC.
Give me a call if interested in a pair.