What is a Line Array?

Conventional speakers transmit sound waves in all directions equally. They then use horns to try to direct the sound wave in the pattern they want. Omni-directional sound waves spread in all directions and drop in loudness 6dB's the farther you get from the speaker. Putting a horn in front of the speaker does not change the nature of the sound waves. You can create different types of sound waves by changing the shape of the speaker. Almost all speakers are round, and therefore create omni-directional sound waves. A more directional sound wave can be produced if the speaker is much longer then it is wide. Since the actual nature of the sound wave is changed, the loudness drops by only 3dB's the farther you get from the speaker. A speaker array uses many small speakers to simulate a large speaker. A vertical line array design creates a 3dB drop-off with great horizontal projection, but little vertical diffusion.