Does anyone know the brand of audio speakers that can focus the spatially audible area to a few square feet?

Question

It was briefly featured on TechNow

Answer 1

I'm not sure of a brand of speakers but there is a technique that focuses audio to only a very small area - it uses out of phase projection or something similar. Heard about it quite a while back. It would be used for ads in shopping areas so that the audio would only be heard by those nearby... here's the closest thing I could find about it ---



http://illumin.usc.edu/article.php?articleID=80



the phase cancellation relationship method used to focus the soundwaves could also be used by multiple speakers to narrow the audible area to a few feet...

Answer 2

Sorry, but this sounds like a gimmick to me. How would any speaker "stop" sound waves traveling through the air? I'd have to hear it to believe it.