In practise it's not possible CyranoAH.
Instead there are new techniques utilizing ultra high frequency transmitters which can beam the sound directly in a wanted direction.
Due to the physical properties of sound the lower the frequency, the less directivity sound has i.e. low sounds spread around the room while high sounds tend to travel in a more straight pattern.
Not surprisingly it is one of the biggest challenges in speaker building to get this behaviour in control.
Knowing this, scientists have developed a way to produce sound through ultrasonic frequencies which you can't normally hear at all, but which produce sound through interference when a subject is bombarded with them. Since very high frequencies are used the sound behaves more like a beam of light, travelling in a narrow beam.
So far they've managed to reproduce a vocal range starting from 1khz up which makes its use for music (or even less movies) hopeless. It does have use for commercial applications - they can make wall posters which scream at you while you pass them - and nobody else will be able to hear that.
http://www.atcsd.com/
