The sound spreads in a certain direction and a designated area like a beam of light, instead of spreading everywhere, this is a directional sound speaker! Directional speakers are also called directional loudspeakers, directional sound speakers, ultrasonic directional speakers, directive speakers, etc.
The emergence of directional speakers has reduced the trouble of noise pollution to some extent. Everyone knows the dangers of noise pollution, which can make people irritable, sensitive, distracted, and have insomnia. With the directional loudspeakers, sound can be delivered only to the area where it needs to be transmitted, and life will become better and more harmonious. It is undoubtedly a great invention to let the sound propagate in a specified direction and realize the division of sound areas.
How do directional speakers work? The directional speaker modulates the audio signal on the ultrasonic waves and uses the characteristics of ultrasonic directional propagation and the nonlinear effect of the air to form the directional propagation of audible sound, so it is also called the ultrasonic directional speaker.
In general perception, sound (audible sound) is transmitted in all directions. But in fact, when a sound wave propagates, the sound pressure in all directions is different. Through the control and processing of the sound source, it can be transmitted along a certain path directional. So that the sound propagates in a specified direction in the form of a narrow-band sound beam, that is, a beam of "sound column" is sent, like the light beam emitted by a searchlight, then only people located in the direction covered by the sound beam can hear the sound.