Conference halls use a very powerful Ultrasonic beam to play language translations to different people fairly far away (30m). The power is from an array of many ultrasonic transducers and a receiver is used. The new method below is also used for translations and the speech seems to come from inside your body.
There is a new method of using a powerful ultrasonic beam of specially modulated speech to bounce off an object in a museum or gallery. When the beam hits the object then it becomes de-modulated and heard to be coming from the object.
I cannot find a link that shows the many ultrasonic transducers in the array.