The Diva was Apogee's most expensive ribbon speaker when it was released in 1988. Nearly as large as the original Full Range it was a 3-way system, slightly over 6 feet tall with a very large trapezoidal bass panel, a 3 element aluminium midrange ribbon and a tweeter made from a single strip of aluminium foil.
The design has an external crossover box with controls for bass (normal-lo), overall midrange level (normal-high), upper midrange (high-normal-lo), and tweeter level (high-normal-lo).
At over 6 feet tall the Diva does tend to dominate a room, although from my experience the bass is better controlled than the Duetta Signature which makes it more room friendly, at least in terms of room interaction in the low frequencies. It does want to be at least 3 feet, and no more than 5 feet from the rear wall, and although the recommended clearance from side walls is at least 10", I have found 2 feet or more helps the imaging considerably.