Defined coverage loudspeaker horn

DETAILED DESCRIPTION A loudspeaker horn for directing sound from a driver having a principal axis of propagation to a target area having a plurality of portions located different distances from the driver comprises: means for radiating a sound beam generated by the driver; and a pair of symmetric opposed side walls extending outwardly from the radiating means, the side walls being constructed and arranged to direct a first portion of the beam toward a first portion of the target over a first preslected included angle, and to direct at least one other portion of the beam toward another portion of the target over a different preselected included angle, the first and second angles being chosen to produce a substantially uniform sound intensity over the target area.
In a preferred embodiment, the target portions are located different distances from the radiating means, and the included angles are chosen such that each portion of the beam, i.
e.
, "beamlet", is substantially coextensive with the respective target portion at a location of incidence thereon.
The side walls substantially define the included angles over regions extending downstream of the radiating means a distance at least comparable to the maximum wavelength at which the loudspeaker is to operate.
In one embodiment, the side walls comprise first and second pairs of opposed walls extending outwardly from the radiating means, which may be a radiating gap, for controlling sound dispersion in the direction of minor and major dimensions, respectively, of the gap.
The second pair of side walls has regions adjacent to the gap which define a uniform preselected included angle emanating from a vertex upstream of the gap, and the first pair of side walls has a portion adjacent to the radiating gap which defines different preselected included angles at different lateral cross sections containing a line which passes through the vertex of the second pair of side walls and is parallel to the direction of the minor dimension.
In the horn of the present invention, the angle of the path provided by the first walls is determined by the line of sight path between the radiating source and the boundary of the target