Abstract: A filter for correcting phase distortion produced at low frequencies in a loudspeaker system is created by inverting the phase response of the determined complex-valued frequency response of a loudspeaker system. The inverted phase response is obtained by taking the complex conjugate of the phase response. The impulse response for the inverted phase response is obtained by means of an inverse Fourier transform of the inverted phase response. The impulse response provides a linear phase FIR filter having a long filter length. The linear phase FIR filter is applied to the audio signal input to the loudspeaker system. Prior to inverting the phase response, the determined complex-valued frequency response of a loudspeaker system can be subjected to high frequency blanking and polynomial smoothing. Also, the linear phase FIR filter can be subjected to a window function prior to applying the filter to the audio signal.

Abstract: A filter for correcting phase distortion produced at low frequencies in a loudspeaker system is created by inverting the phase response of the determined complex-valued frequency response of a loudspeaker system. The inverted phase response is obtained by taking the complex conjugate of the phase response. The impulse response for the inverted phase response is obtained by means of an inverse Fourier transform of the inverted phase response. The impulse response provides a linear phase FIR filter having a long filter length. The linear phase FIR filter is applied to the audio signal input to the loudspeaker system. Prior to inverting the phase response, the determined complex-valued frequency response of a loudspeaker system can be subjected to high frequency blanking and polynomial smoothing. Also, the linear phase FIR filter can be subjected to a window function prior to applying the filter to the audio signal.

Abstract: A method for correcting magnitude and phase distortion in open ear hearing devices includes determining the insertion effect of the hearing device (12) substantially at the ear drum (11) when in the ear. Both the magnitude and phase response of the complex insertion transfer function (ITF) are corrected when the transfer function to the ear drum substantially matches the transfer function without the hearing device in place.

Abstract: A filter for equalizing the frequency response of loudspeaker systems includes at least one band filter section (11) comprised an n-order high boost or cut shelving fitter (13) having a break point frequency, ?1, and an n-order low boost or cut shelving filter (15) having a break point frequency, ?2, wherein ?1<?2. The order, n, of at least one, and preferably both of the shelving filters of the band filter sections can be selected for adjusting the slope of the shelving filter at one or both of its break point frequencies. The high and low n-order shelving filters forming the band filter sections have substantially the same gain and produce a resultant band gain for the band filter section. Gain correction is provided for the selectable n-order high shelving filter and n-order low shelving filter for correcting the resultant band gain to a base gain level.

Abstract: A method for correcting magnitude and phase distortion in open ear hearing devices includes determining the insertion effect of the hearing device (12) substantially at the ear drum (11) when in the ear. Both the magnitude and phase response of the complex insertion transfer function (ITF) are corrected when the transfer function to the ear drum substantially matches the transfer function without the hearing device in place.

Abstract: A method for correcting magnitude and phase distortion in open ear hearing devices includes determining the insertion effect of the hearing device substantially at the ear drum when in the ear. Both the magnitude and phase response of the complex insertion transfer function (ITF) are corrected when the transfer function to the ear drum substantially matches the transfer function without the hearing device in place.

Abstract: A filter for equalizing the frequency response of loudspeaker systems includes at least one band filter section (11) comprised an n-order high boost or cut shelving fitter (13) having a break point frequency, ?1, and an n-order low boost or cut shelving filter (15) having a break point frequency, ?2, wherein ?1<?2. The order, n, of at least one, and preferably both of the shelving filters of the band filter sections can he selected for adjusting the slope of the shelving filter at one or both of its break point frequencies. The high and low n-order shelving filters forming the band filter sections have substantially the same gain and produce a resultant band gain for the band filter section. Gain correction is provided for the selectable n-order high shelving filter and n-order low shelving filter for correcting the resultant band gain to a base gain level.

Abstract: An improved filtering system for loudspeaker equalization is comprised of two filtering sections, a single pole filtering section having single pole filters for shaping the frequency response of the audio signal over the operative bandwidth of the equalized loudspeaker system, and a parametric filtering section that provides for localized parametric equalization for compensating for room or other environmental resonances. The filtering system of the invention can be used to create a wide variety of useful filter shapes, while minimizing phase distortion that can harm the transient response of phase-aligned loudspeakers of a loudspeaker system.

Abstract: A loudspeaker system has a plurality of relatively small transducer elements configured in a closely spaced transducer array such that their acoustic outputs combine to produce a focused beam of sound in front of the array that is substantially uniform about the beams radiation axis. The transducer array lies in a plane and has a perimeter that approximates a circle, and will have fill-factor with respect to a circle circumscribing the array of at least approximately 70%. In one variation of the loudspeaker system, the transducer array is constructed in smaller transducer array modules that are operatively fitted together to produce a larger array.

Abstract: A loudspeaker system has a plurality of relatively small transducer elements configured in a closely spaced transducer array such that their acoustic outputs combine to produce a focused beam of sound in front of the array that is substantially uniform about the beams radiation axis. The transducer array lies in a plane and has a perimeter that approximates a circle, and will have fill-factor with respect to a circle circumscribing the array of at least approximately 70%. In one variation of the loudspeaker system, the transducer array is constructed in smaller transducer array modules that are operatively fitted together to produce a larger array.

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 loudspeaker system has of a plurality of relatively small, closely spaced transducer elements, the acoustic outputs of which combine to create a sound field. The transducer elements are individually controlled by a distributed input control circuit, which includes digital signal processing, to synthesize a sound field in front of the transducer elements with a characteristic beam width and direction.

Abstract: A web hosted system and user interface in 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 web hosted system and user interface in 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 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 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.