The sound pressure coverage of line array acoustics is close to the so-called line sound source theory, and the level will not drop 6dB when the listening distance is doubled. In theory, it will only drop by 3dB, but in practice, the result is not so ideal. Why these differences exist is not discussed in detail in this paper. But even so, compared with the point source speakers, linear array speakers have unique advantages in vertical coverage Angle. With linear sound radiation characteristics of a speaker can achieve the following results: you can in the lobby or outdoor space of the rear area feel relatively large sound pressure level, and in order to do this, you don't need, like operating common point source speakers, increase their power to get in front of the PA system closer to hear the sound of the too big. Its advantage lies in the complex and variable control of the vertical diffusion Angle of sound.
How to realize linear sound source radiation
The phase offset
Phase cancellation is usually one of the things that engineers try to avoid in sound systems, but it plays a central role in providing a narrow vertical coverage Angle when linear array speakers work together. Even with the use of a high-level speaker box design to shape the vertical coverage, there is still a lot of actual overlap between the speakers in the in-line array. In other words, the vertical coverage Angle of linear array speakers is not formed by a single speaker, but by the effective interference of multiple speakers at the outlet. In reality, however, the distance between each wire array speaker and the viewer is slightly different, causing a small amount of phase cancellation. Of course, you can also manually and subtly adjust the vertical coverage Angle of the wire-array speakers by introducing electronic delay (EAW Anya and Anna systems apply this technique).