Deep Model 16; interesing use of a compression driver.

[tade]

This is a really cool loudspeaker design that I just ran across. Take a look!
http://www.deepaudio.net/

The nicest drivers I own are a pair of Altec model 288c large format HF compression drivers, and I have been questing for a way to use them. Naturally this loudspeaker piqued my interest especially considering that I wont have to make a horn!

But I have questions about their design. First of all, does the efficiency drop down to that of a normal dynamic driver without a horn attached? Does the driver behave like a plane wave tube with a length of the depth of the driver? Does the driver suffer from the 6 db per octave roll off of the high frequencies, and can this be compensated for?

I wonder if their design goals of having an extremely powerful motor controlling a lightweight diaphragm radiating from a small source to avoid beaming are sound design ideas.

I wonder if putting a radius at the front of the driver large enough to avoid diffraction down to the frequency that the driver becomes monopolar, And then compensating for high frequency roll off would yield a really nice low distortion and extended range hf driver.

any thoughts welcome!

[CeramicMan]

I'm guessing that the compression driver could be very inefficient without a horn, due to it's high BL and low Q parameters. And the small back chamber could give it a high cut-off frequency... Though I could be wrong.