very directional speaker technology

[amdx]

Anybody heard these speakers?

Looking for a discussion of this technology.
It would be a neat homebrew project!

http://www.holosonics.com/technology.html

http://www.holosonics.com/brochure/Audio_Spotlight_Specifications.pdf

http://www.holosonics.com/products.html


What frequency is the ultrasound?
Do some systems mix two ultrasound sources?
There is correction for nonlinearity of air is that correction
performed at ultrasound frequency or audio frequency?

Here's a couple of youtube videos about the subject.
I'd like to hear your input.
Note the bnc connector to the speaker!
Mike