Patent ID: 6466680
Filing Date: 2002-10-15
Classification: H04R

Abstract:
An improved high-frequency loudspeaker module of the compression-driven type for deployment behind a perforated cinema screen of a theater to provide uniform sound coverage across a designated high-frequency audio range in a target auditorium area of the theater, comprising:a compression driver; and an acoustic waveguide having a sound entry end coupled acoustically and mechanically to said compression driver, said acoustic waveguide being configured internally to have a horn shape, disposed about a central axis, with a cross-sectional area that increases smoothly and progressively from the sound entry end and extending through a mid region to an enlarged flared sound exit end constituting an acoustic output port, the internal horn shape being made and arranged to provide, as measured in the absence of the perforated screen, a directivity pattern of the loudspeaker module alone that is made to decrease in beamwidth as a function of frequency within the high-frequency audio range in a manner that approximates an inverse function of beam-spreading effects of the perforated screen, so that when the loudspeaker module is deployed behind the perforated screen facing the theater auditorium target area, compensation is provided for high-frequency beam-spreading effects of the perforated cinema screen to accomplish overall an unusually high degree of uniformity in audio coverage throughout the target area.