A column loudspeaker with a line of low-frequency drivers has a center coaxial driver with a low frequency driver and a high frequency drive. The low frequency drivers are delayed and gain adjusted such that they exhibit constant directivity in the axis of the line. The high frequency driver has the same directivity as the line of low frequency drivers. A crossover separates the audio signal into high and low frequency signals with low frequency signals sent to the low frequency drivers, and high frequency signals sent to the high frequency element in the coaxial driver. The crossover frequency is in the frequency range where the directivity of the high and low frequency drivers match. The loudspeaker cabinet is curved to provide an acoustic delay to the drivers further away from the center coaxial driver.

Method for approximating the synthesis of a target sound field based on contributions of a predefined number of synthesis monopoles placed at respective synthesis positions, the method comprising modelling the target sound field as at least one target monopole placed at a defined target position.

A waveguide for conducting sound that is generated by a loudspeaker that is acoustically coupled to the waveguide. There is a duct with an external wall, an interior opening circumscribed by the wall, and an outlet, and an air-adsorbent structure coupled to an inside of the external wall of the duct such that the air adsorbent structure lines at least a portion of the wall. The apparent volume ratio of the air adsorbent structure is at least about 1.5.

A waveguide for conducting sound that is generated by a loudspeaker that is acoustically coupled to the waveguide. There is a duct with an external wall, an interior opening circumscribed by the wall, and an outlet, and an air-adsorbent structure coupled to an inside of the external wall of the duct such that the air adsorbent structure lines at least a portion of the wall. The apparent volume ratio of the air adsorbent structure is at least about 1.5.

A phase plug for a loudspeaker having a driven diaphragm, wherein at least a portion of the surface of the phase plug disposed in use adjacent the diaphragm is generally annular in two orthogonal directions and has an axis in a third orthogonal direction, and wherein at least a portion of the said annular surface is shaped such that as successive radial cross-sections through the annular surface are generated by rotating a plane about the axis, the cross-sectional shape of the surface of the phase plug varies periodically as the angle of rotation increases.

A phase plug for a loudspeaker having a driven diaphragm, wherein at least a portion of the surface of the phase plug disposed in use adjacent the diaphragm is generally annular in two orthogonal directions and has an axis in a third orthogonal direction, and wherein at least a portion of the said annular surface is shaped such that as successive radial cross-sections through the annular surface are generated by rotating a plane about the axis, the cross-sectional shape of the surface of the phase plug varies periodically as the angle of rotation increases.

In one embodiment, a MEMS microphone can be coupled to an acoustic horn to provide various benefits and improvements including, but not limited to, at-a-distance acoustic signal reception with improvements in signal-to-noise ratio and directional preference.

In one embodiment, a MEMS microphone can be coupled to an acoustic horn to provide various benefits and improvements including, but not limited to, at-a-distance acoustic signal reception with improvements in signal-to-noise ratio and directional preference.

A loudspeaker array has a cabinet in which is formed a continuously open circumferential horn for controlling sound produced by a number of transducers which are positioned in the cabinet, at a throat of the horn. The continuously open circumferential horn may 1) improve the power efficiency of the transducers without unwanted aliasing effects in audible frequency ranges and 2) provide vertical control for sound emitted by the transducers by flaring.

A loudspeaker array has a cabinet in which is formed a continuously open circumferential horn for controlling sound produced by a number of transducers which are positioned in the cabinet, at a throat of the horn. The continuously open circumferential horn may 1) improve the power efficiency of the transducers without unwanted aliasing effects in audible frequency ranges and 2) provide vertical control for sound emitted by the transducers by flaring.