Through our devices sound is transmitted in one direction, while the overall silence is maintained in the rest of the room. The device uses modulated ultrasound technology. Two speakers emit sound waves in the range of 40 to 80 kHz, and a nonlinear medium acts as a demodulator. As the waves propagate in the air, pulses of audible frequencies appear in the ultrasound. The applications for Directional Sound are varied! The system is suitable for dividing sound zones in a car, or as a sound system for exhibitions, showrooms and billboards.