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.