Abstract: A loudspeaker array comprising line sources, each of which comprises a curved one dimensional array of loudspeakers. The loudspeakers have horizontal dispersion angles of less than 60°. Adjacent pairs of loudspeakers of each line source are time-aligned in a direction bisecting their propagation axes, which are in a common vertical plane.

Abstract: A loudspeaker array comprising line sources, each of which comprises a curved one dimensional array of loudspeakers. The loudspeakers have horizontal dispersion angles of less than 60°. Adjacent pairs of loudspeakers of each line source are time-aligned in a direction bisecting their propagation axes, which are in a common vertical plane.

Abstract: An upper base/low mid loudspeaker comprises a conical driver and a channel defined by a housing and a central member. The central member has a portion extending into the cone to form a first generally ring-shaped region whose cross-sectional area increases in the direction of sound propagation. A second generally ring-shaped region is defined between a portion of the housing and a portion of the central member. The cross-sectional area of the second region decreases in the direction of sound propagation. The channel continues with a throat and a horn.

Abstract: An improved adaptor for coupling a plurality of compression drivers to the throat of a common horn is disclosed. The improved adaptor of the present invention includes a passage coupled to each of the plurality of compression drivers, the passages extending forwardly toward the horn. A longitudinally extending central member is mounted within the horn flare, extending along its central axis and tapering forwardly. The surfaces of the horn flare and the central member define an annular region between the side walls of the horn flare and the central member. The passages for each of the compression drivers are connected with this annular region. The adaptor therefore comprises a manifold whose passages operate into three symmetrical sectors of the annular passage formed by the insertion of the central member into the horn flare.

Abstract: An improved sound reinforcement enclosure is disclosed which incorporates a cone-type loudspeaker operating into a generally cylindrical channel extending from the perimeter of the cone to free air. A central member is coaxially mounted within this channel, the central member having rear surfaces substantially parallel to the surface of the cone and external surfaces which, with the internal surfaces of the channel form an annular region, the central member also having at least one coaxial internal passage forming a concentric horn flare. Methods of coaxially mounting a high-frequency compression driver behind the magnet assembly of the loudpseaker and of mounting a second loudspeaker internally in an enclosure are also disclosed.

Abstract: A condenser including a condenser chamber having an extension portion extending through the base of a refrigerant storage vessel. The length of the conduction path along this portion is variable. This may be performed by partial retraction of the extension from the vessel, or by inclusion of one or more insulating shields. Both extension and shield may be threaded. The vessel may be of thin stainless steel or compliant solid insulating material, allowing fine adjustment of the conductive path length by tightening of the shield against the base of the vessel. The internal surface of the chamber may be undulated, in particular by threading, to promote turbulent flow and mixing within the chamber. The extension may be recessed and joined to a filling tube, to facilitate initial cool down. The complete condenser is encased by expanded polyurethane foam inside a box.

Abstract: A bass sound projection system comprises a cabinet containing at least one bass loudspeaker operating into a sound channel. The sound channel converges forwardly, relative to the direction of propagation of sound waves, of the loudspeaker to a throat and then diverges forwardly, relative to the direction of propagation of sound waves, of the throat to an acoustically open front end of the cabinet. The system may include a further bass loudspeaker and sound channel arranged as a mirror image of the first bass loudspeaker and sound channel, and the or each sound channel may be folded.