Applications
The precedence effect is important for the hearing in enclosed rooms. With the help of this effect it remains possible to determine the direction of a sound source (e.g. the direction of a speaker) even in the presence of wall reflections.
Sound reinforcement systems in big rooms use the Haas effect, in order to enhance the sound level for distant locations. For this purpose the loudspeakers at distant locations emit the same sound signal as the direct sound at the listener's location, but the loudspeaker signals are enhanced by up to 10 dB and are emitted 20 ms after the direct sound arrives at the listener. In this configuration the listener will localize all sound from the direction of the direct sound, but he will benefit from the higher sound level, which has been enhanced by the loudspeakers.
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