Abstract: A noise generator and method are provided for generating a test signal for measuring the performance of a loudspeaker over an operating broad band of frequencies ranging from low to high frequencies. A broadband random noise source is provided for generating broadband noise over the operating broad band of frequencies of the loudspeaker, and an impulsive noise source is additionally provided for generating random impulses of noise. The broadband noise and the randomly generated noise impulses are equalized to produce a composite noise signal having a desired crest factor as a function of frequency.

Abstract: An improved open-ear hearing aid to compensate for hearing loss includes a microphone for picking up incident sound and converting it to an electrical audio signal. An ear insert positionable within a human ear canal is provided for producing an output sound amplified within one or more frequency bands in response to incident sound picked up by the microphone. The in-band gain of the amplified sound output of the ear insert's loudspeaker is dependent on the user's hearing loss characteristics and the sound pressure levels of the incident sound. The form of the ear insert allows transmission of incident sound directly to the eardrum, where it is summed at the eardrum with the amplified sound output from the ear insert. Sound output is maximum at low incident sound pressure levels and minimum when the incident sound exceeds a set cut-off level.

Abstract: The hearing aid includes a signal processor having a level-dependent filter section and a level-independent filter section. The level-dependent filter section provides level-dependent gain wherein sound is attenuated or amplified depending on the level of the incoming sound. The level-independent filter section provides substantially constant gain wherein sound that passes through the filter section is not changed in level, and provides transparency in that it corrects for insertion loss caused by the earpiece of the hearing aid when worn by the user. The level dependent and level independent filter sections, when fitted to the user, greatly improve the user's perception of sound.

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: An arrayable loudspeaker (11) has at least one high frequency driver (39) mounted to a horn (37) and at least one pair of low frequency drivers (41) configured behind and in a closely spaced relationship to the horn to form low frequency side chambers (71) between the drivers and the horn from which acoustic energy produced by the low frequency drivers can propagate. Low frequency exit channels (77) above and below the horn are coupled to the low frequency side chambers (71). The configuration of the horn and low frequency drivers and the low frequency side chambers and low frequency exit channels is such that acoustical outputs of all drivers radiate coaxially from the loudspeaker with substantially constant wide beamwidth in the non-arraying plane. Signal processing can be added to enhance beamwidth control critical frequency ranges above crossover.

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 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: An acoustic control system for hospitality spaces includes a passive component (17) for producing a baseline reverberation time (RT) value within the space, and an active component (LN, MN, 15) for picking up sounds in the space (11) and reintroducing the sounds into the space such that the reintroduced sounds have an RT value and sound level capable of being adjusted and such that the resulting RT value can be adjusted to a relatively large value as compared to said baseline RT value.

Abstract: An improved open-ear hearing aid to compensate for hearing loss includes a microphone for picking up incident sound and converting it to an electrical audio signal. An ear insert positionable within a human ear canal is provided for producing an output sound amplified within one or more frequency bands in response to incident sound picked up by the microphone. The in-band gain of the amplified sound output of the ear insert's loudspeaker is dependent on the user's hearing loss characteristics and the sound pressure levels of the incident sound. The form of the ear insert allows transmission of incident sound directly to the eardrum, where it is summed at the eardrum with the amplified sound output from the ear insert. Sound output is maximum at low incident sound pressure levels and minimum when the incident sound exceeds a set cut-off level.