Abstract: A loudspeaker is disclosed. The loudspeaker includes a rigid frame, a diaphragm is firmly attached to the frame. A plurality of transducers attached to the diaphragm. In use, the loudspeaker radiates acoustic energy by pistonic motion of the diaphragm in response to actuation by the plurality of transducers. The motion of the diaphragm is in a substantially fundamental mode.

Abstract: A loudspeaker system has a diaphragm for producing sound, a loudspeaker driver mechanism operable for moving the diaphragm in response to an applied electrical signal from an audio signal source, a blower positioned for directing air under pressure over the loudspeaker driver mechanism so that heat generated by the loudspeaker driver mechanism can be convectively removed, and a control circuit electrically connected to the blower and adapted for connection to the audio signal source such that an increase in the applied electrical signal causes a corresponding increase in speed of the blower. The control circuit includes a power limiting device and a switching device that is connected in parallel with the power limiting device. The switching device is actuable from a normally closed state to an open state when the applied electrical signal is above a predetermined level to regulate the speed of the blower.

Abstract: A thermal protection circuit for a loudspeaker system includes a load device that is connected in series with a loudspeaker driver mechanism, and a thermally sensitive resettable switch that is connected in parallel with the load device and thermally connected to the loudspeaker driver mechanism, such that heat generated by the loudspeaker driver mechanism is at least conductively transferable to the switch. The switch is changeable between a closed state wherein the load device is at least substantially bypassed, and an open state wherein the electrical signal from an amplifier or crossover circuit is at least substantially directed through the load device when a temperature of the switch is above a predetermined temperature and the electrical signal is above a predetermined signal level. As the temperature of the loudspeaker driver mechanism increases, the temperature of the switch also increases, which in turn decreases the signal level required to trip the switch.

Abstract: A thermal protection circuit for a loudspeaker system includes a load device that is connected in series with a loudspeaker driver mechanism, and a thermally sensitive resettable switch that is connected in parallel with the load device and thermally connected to the loudspeaker driver mechanism, such that heat generated by the loudspeaker driver mechanism is at least conductively transferable to the switch. The switch is changeable between a closed state wherein the load device is at least substantially bypassed, and an open state wherein the electrical signal from an amplifier or crossover circuit is at least substantially directed through the load device when a temperature of the switch is above a predetermined temperature and the electrical signal is above a predetermined signal level. As the temperature of the loudspeaker driver mechanism increases, the temperature of the switch also increases, which in turn decreases the signal level required to trip the switch.

Abstract: A loudspeaker system has a diaphragm for producing sound, a loudspeaker driver mechanism operable for moving the diaphragm in response to an applied electrical signal from an audio signal source, a blower positioned for directing air under pressure over the loudspeaker driver mechanism so that heat generated by the loudspeaker driver mechanism can be convectively removed, and a control circuit electrically connected to the blower and adapted for connection to the audio signal source such that an increase in the applied electrical signal causes a corresponding increase in speed of the blower. The control circuit includes a power limiting device and a switching device that is connected in parallel with the power limiting device. The switching device is actuable from a normally closed state to an open state when the applied electrical signal is above a predetermined level to regulate the speed of the blower.

Abstract: An apparatus and method for centering a voice coil in a loudspeaker having a vented pole piece. The voice coil centering is accomplished by means of a concentrically located voice coil suspension and an attached cylindrical mounting ring that can be set into a recess, or otherwise positively located on the pole piece. The pole piece is formed in such a way so as to precisely receive a suspension mounting ring and center the voice coil in the magnetic field gap with no further adjustments. This invention permits the use of a pole piece mounted voice coil suspension on a ventilated pole piece.

Abstract: A loudspeaker horn which provides constant coverage angles in both the horizontal and vertical planes and affords proper driver loading and a smooth impedance curve down to the lowest frequencies of operation. The throat entrance of the horn is round, to match the driver exit hole, and the throat section expands exponentially, with substantially straight and divergent top and bottom walls and curved side walls. The throat section joins to a transition section in which the side walls expand outward at a more rapid rate and a central vane is introduced top to bottom that both maintains an exponential flare rate and divides the transition section into two vertical slits. The length and width of the transition section are determined by the upper limits of the frequency range and the horizontal coverage angle. The transition section joins to the wave guide section which has a substantially planar side walls forming a conical expansion wave guide with side angle equal to the coverage angles of the horn.

Abstract: A loudspeaker having uniform horizontal sound dispersion characteristics in a design angle and minimal sound dispersion vertically comprises multiple sound energy sources forming an elongated line source of sound energy, and a waveguide having an elongated input portion coextensive with the elongated line source and substantially planar side walls defining an expanding cross-section from the input portion to an exit aperture, whereby sound dispersion in a direction parallel to the line source is minimized. The waveguide expands substantially only in a direction perpendicular to the line source, the rectangular input portion having substantially the same dimension as the exit aperture measured in the direction parallel to the line source.