Abstract: A side frame for a loudspeaker rigging system has a frame structure mountable to the side of a loudspeaker, and links associated with the frame structure for linking together the corners of the frame structures of vertically adjacent side frames. The links associated with each side frame structure include a pivot link and splay adjustment link, each of which has a top extended end and a base end with a seating edge. Guide channels, which are located in the top corner regions of the frame structure to receive the base ends of a pivot link and splay adjustment link associated with a vertically adjacent side frame, have seating surfaces that conform to the seating edges at the base ends of the pivot and splay adjustment link. When base ends of these links seat in the guide channels, pin holes in the base end of the links self-align with pin holes in the corners of the frame structure for easy insertion locking pins.

Abstract: A circuit and method provides for the protection of transducers from over excursion, particularly for the protection of transducers for audio loudspeakers. A frequency dependent excursion limiter circuit has an initial summing stage followed by a shaping filter stage. A clamping function is provided at the summing stage, or at a separate stage between the summing stage and the shaping filter stage, for clamping the driving signal at a predetermined maximum voltage if the driving signal exceeds the predetermined maximum voltage level. The shaping filter stage provides a frequency response shaping function based on a predetermined frequency response shaping criteria which is related to the frequency dependent excursion limits of the transducers being protected from mechanical overload. An inverse shaping filter function is provided at the initial summing stage by providing feedback from the shaping filter stage, thus eliminating the need for a separate inverse shaping filter circuit before clamping.

Abstract: A web hosted system and method involving a client-server architecture permits audio designers to perform acoustic prediction calculations from a thin client computer. A client computer or other Internet connect device having a display screen is used by an audio professional to access via the Internet a host computer which performs acoustic prediction calculations and returns results of the calculations to the client. The results of the calculations are returned in the form of data visualizations, such as an area view showing visualizations of sound pressure levels within a defined space, an impulse view showing the time domain response at a defined location, and/or a frequency domain view showing the frequency response at a defined location. Calculations are performed based on user-defined inputs, such as speaker type and location, sent to the host computer from the client computer and based on retrieval of loudspeaker data from one or more databases accessible by the host computer.

Abstract: A loudspeaker horn (11) having a throat end (13) for receiving acoustic power from aligned acoustic power sources (41, 43, 45), an elongated throat (33), and a flared section (17) is provided with grating lobe mitigation fins (27, 29) that extend substantially parallel to the propagation axis of the horn from the throat end toward the mouth end of the horn's flared section. The length of the grating lobe mitigation fins is established in accordance with the degree of suppression of the grating lobes produced by the aligned acoustic power sources that is desired.

Abstract: A manifold for a horn loudspeaker has an input end having at least one input port for receiving acoustic power from at least one acoustic driver, and an output end for delivering acoustic power to the throat end of the horn. The output end of the manifold has at least two and suitably multiple output ports. An acoustic power waveguide is provided for each output port and connects each of the output ports to the input port of the manifold. Acoustic power received by the input port is divided between the acoustic waveguides such that it is delivered to the aligned output ports to simulate a line array of acoustic power sources.

Abstract: A rigging system for flying a vertical stack of loudspeakers includes left and right rigging side frames (15, 17). Each rigging side frame includes a frame structure having a top end (43), a bottom end (45), and rear and front corners (51, 53, 55, 57) which is mountable to the side of a correspondingly sized loudspeaker (13). Each rigging side frame further includes a rear link (59) for pivotally linking the rear corner of a rigging frame of one loudspeaker to the rear corner of the same side rigging frame of another loudspeaker placed in stacked relation therewith, and a cam plate link (61) pivotally attached to a cam pivot point (85) at one of the top or bottom ends of the frame structure in displaced relation to the cam link. Two or more link openings (143) are provided in the cam plate link at different angles about the cam plate link pivot point and at different radial distances from the cam plate pivot point.

Abstract: A rigging system for flying a vertical stack of loudspeakers includes left and right rigging side frames (15, 17). Each rigging side frame includes a frame structure having a top end (43), a bottom end (45), and rear and front corners (51, 53, 55, 57) which is mountable to the side of a correspondingly sized loudspeaker (13). Each rigging side frame further includes a rear link (59) for pivotally linking the rear corner of a rigging frame of one loudspeaker to the rear corner of the same side rigging frame of another loudspeaker placed in stacked relation therewith, and a cam plate link (61) pivotally attached to a cam pivot point (85) at one of the top or bottom ends of the frame structure in displaced relation to the cam link. Two or more link openings (143) are provided in the cam plate link at different angles about the cam plate link pivot point and at different radial distances from the cam plate pivot point.

Abstract: An arrayable loudspeaker system having a horn-loaded high frequency compression driver and a low frequency cone driver radiates acoustic energy from a focal point in a polar radiation pattern having amplitude and phase and includes a signal conditioning circuit for amplitude equalization and phase correction. The horn of the system's horn-loaded compression driver is designed in cooperation with the signal conditioning circuit such that the focal point of the loudspeaker system is substantially frequency independent over the operating frequency range of the loudspeaker system and such that over this operating frequency range the loudspeaker's focal point remains substantially fixed in space. Any two or more of such loudspeaker systems can be arrayed by aligning them in respect to their frequency independent focal points and by rotating the loudspeakers about an axis passing through the aligned focal points to obtain a desired coverage.

Abstract: A loudspeaker horn for use with an acoustical driver has a rectangular throat opening with a long dimension relative to the wavelength of the sound pressure waves generated within the high frequency range of the horn. A relatively short pre-load chamber corrects the phase of the sound pressure waves over the long dimension of the throat opening. The pre-load chamber provides control over the directivity of the horn and provides a uniform frequency response with minimal distortion.

Abstract: An acoustical transmitting system and method for producing a narrow beam of acoustic energy over a broadband operating frequency range utilizes a parabolic reflector dish, a horn-loaded compression driver for directing acoustic energy toward the dish's reflecting surface, and a low frequency driver mounted behind a central aperture in the dish for producing acoustic energy that combines and interacts with the reflected acoustic energy produced by the horn-loaded compression driver. An input signal processing circuit is provided to condition the audio signal to the horn-loaded compression driver and the low frequency driver to achieve on-axis gain and off-axis cancellations at low frequencies. The addition of the low frequency driver to the reflector dish system effectively extends the ability of the system to produce and transmit acoustic energy in a narrow distribution pattern at frequencies below 1000 Hz using a four foot diameter dish.

Abstract: A method and correction circuit for improving and controlling the listening window and response of a two-way loudspeaker system utilizing a horn-loaded high frequency driver. The correction circuit includes adjustable active all-pass and band-pass filters, in a specific arrangement, coupled with conventional cross-over filters to achieve a maximally flat amplitude and phase response acoustically throughout a preferred listening window. A spectrum analyzer measures the near-field responses of the individual and combined transducers while adjustments are made. A phase shifting circuit is included in the low frequency channel which results in improved near-field to far-field response consistency and significantly improves the subjective characteristics of the high frequency horn.

Abstract: A bass reflex loud speaker system for use in high power applications which includes an enclosure with at least two, and preferably three, cone drivers mounted in front of separate and acoustically isolated bass reflex chambers. Each bass reflex chamber is tuned to a separate octave such that the bass reflex modules formed by each bass reflex chamber and its associate cone driver produces a complex acoustical signal comprised of different frequency components in the low frequency range at high sound pressure levels, but with minimum driver cone excursion and distortion.

Abstract: A circuit for improving the transient behavior of a two-way loudspeaker system includes a crossover circuit with high selectivity, amplitude and phase correction circuitry for separately correcting the amplitude and phase responses of the high and low frequency drivers in their mounting environment, and correction circuitry for correcting the composite amplitude and phase response of the overall loudspeaker system after insertion of the crossover. A further phase offset technique and circuit provides for introducing frequency dependent phase shift in the loudspeaker system's high or low frequency channels for offsetting the phase responses of the high and low frequency drivers within the crossover frequency range. According to the phase offset technique of the invention, phase shift is added, preferably in the high frequency channel, until composite amplitude response curves observed on-axis and at different vertical angles off-axis are forced to be consistent.

Abstract: A circuit for improving the transient behavior of a two-way loudspeaker system includes a crossover circuit with high selectivity, amplitude and phase correction circuitry for separately correcting the amplitude and phase responses of the high and low frequency drivers in their mounting environment, and correction circuitry for correcting the composite amplitude and phase response of the overall loudspeaker system after insertion of the crossover. A further phase offset technique and circuit provides for introducing frequency dependent phase shift in the loudspeaker system's high or low frequency channels for offsetting the phase responses of the high and low frequency drivers within the crossover frequency range. According to the phase offset technique of the invention, phase shift is added, preferably in the high frequency channel, until composite amplitude response curves observed on-axis and at different vertical angles off-axis are forced to be consistent.