A loudspeaker (10) has a vertically-elongated cylindrical cabinet which houses both a waveform generator (54) and a pair of sub-woofers (46, 48). The sub-woofers (46, 48) are situated near the top and bottom of the cylindrical cabinet and generate a uniform low frequency response which has in-time coherence with a cylindrical wavefront produced by the generator (54).
An electrostatic transducer includes a thin flexible diaphram portion, two electrode portions and a frame portion. The electrode portions and the diaphram portions are constructed in accordance with U. S. Pat. No. 3,668,335. The frame portion is comprised of two single-piece frame halves each having an "L" shaped cross section with vertical and horizontal legs. The vertical legs include channels cut into their longer dimensions. Each frame-half piece is bent into a rectangular shape to surround one of the electrodes which is retained within the frame-half by a bead of epoxy which extends into the channels on the frame-half to make a relatively rigid frame-half and electrode assembly. Two such assemblies are then affixed to each other with the diaphram tightly stretched in between.
An electrode (13) has a nonconductive substrate (15) and a conductive layer (16) having a first plurality of holes (18) applied to the substrate which is then coated with a dielectric layer (20) wherein the dielectric layer has a relatively low resistivity (e. g. 10. sup. 11 ohm cm). A second and third plurality of holes (700,710), concentric with but of smaller diameter than the first plurality of holes (18), are formed through the dielectric layer (20) and the nonconductive substrate (15), thereby providing a recess spacing (19) between the conductive layer holes (18) and the holes (700,710). In one embodiment of an electrostatic transducer (11), two electrodes (13) are spaced from a diaphragm (12) positioned therebetween. An electrostatic transducer (40) having multiple diaphragms (12,21) is made by incorporating two types of electrodes (13,28). One type of electrode (13) has one side of a nonconductive substrate (15) coated with a conductor (16) and a dielectric layer (20).
Wide Angle Cylindrical Wave Loudspeaker Extending Approximately From Floor To Ceiling Height With A Lens
Loudspeaker and stereophonic system employing hemicylindrical wave form generators, in which the vertical extent of the speaker includes and spans the levels of seated and erect standing listeners, approximating a floor to ceiling height. Two such speakers are placed in a room, directed toward each other and spaced from an end wall, with arc of sound emission of each such that the listener region receives direct sound and two first order reflections, from side and end walls, from each of the two speakers. The path lengths are shown different in length greater than the minimum separate-source discrimination time.