Abstract: According to one embodiment, a pressure sensor includes a base, and a first sensor unit. The first sensor unit includes a first transducer thin film, a first strain sensing device and a second strain sensing device. The first strain sensing device includes a first magnetic layer, a second magnetic layer, and a first intermediate layer provided between the first and the second magnetic layers. The second strain sensing device is provided apart from the first strain sensing device on the first membrane surface and provided at a location different from a location of the barycenter, the second strain sensing device including a third magnetic layer, a fourth magnetic layer, and a second intermediate layer provided between the third and the fourth magnetic layers, the first and the second intermediate layers being nonmagnetic. The first and the second strain sensing devices, and the barycenter are in a straight line.

Abstract: According to one embodiment, a rotating blade noise reduction device for reducing noise from a flight vehicle including rotating blades, the device includes loudspeakers, one or more reference microphones, an estimator, and a processor. The loudspeakers are arranged coaxially in a circumferential form for each of the rotating blades. The reference microphones acquire noise generated from the rotating blades and control sounds generated from the loudspeakers. The estimator estimates angular frequencies of the rotating blades. The processor generates control signals so as to reduce sound pressures at the reference microphones, delays the control signals by time delays corresponding to the loudspeakers dependent on installation angles between the loudspeakers arranged coaxially in a circumferential form from a circle center, the angular frequencies estimated, and a number of the loudspeakers, and inputs the control signals to the loudspeakers.

Abstract: According to one embodiment, a loudspeaker is provided in a case of an earphone. The case closes an external auditory canal extended from a tympanum of a listener. The earphone has an opening toward the external auditory canal. In an apparatus for generating a sound reproduction to the loudspeaker, a storage unit stores a correction filter in which a maximum of a gain at a frequency band lower than or equal to 10 kHz is larger than a maximum of a gain at a frequency band higher than 10 kHz. An acquisition unit acquires a first sound reproduction signal. A correction unit generates a second sound reproduction signal by convoluting the correction filter with the first sound reproduction signal. An output unit outputs the second sound reproduction signal to the loudspeaker.

Abstract: According to one embodiment, a vibration power generator includes a housing, an elastic member, a mover, and a coil. The elastic member is fixed to the housing. The mover is supported by the elastic member and able to vibrate in a first direction. The coil is positioned inside the mover. The mover includes a first magnet, a second magnet, a third magnet, and a first magnetic yoke. The second magnet is placed to be aligned with the first magnet in the first direction so as to repel each other. The third magnet is placed annularly with respect to the first magnet and the second magnet. The first magnetic yoke surrounds the first magnet, the second magnet and the third magnet. The coil is positioned between the third magnet, and both the first magnet and the second magnet.

Abstract: According to one embodiment, a pressure sensor includes a base, and a first sensor unit. The first sensor unit includes a first transducer thin film, a first strain sensing device and a second strain sensing device. The first strain sensing device includes a first magnetic layer, a second magnetic layer, and a first intermediate layer provided between the first and the second magnetic layers. The second strain sensing device is provided apart from the first strain sensing device on the first membrane surface and provided at a location different from a location of the barycenter, the second strain sensing device including a third magnetic layer, a fourth magnetic layer, and a second intermediate layer provided between the third and the fourth magnetic layers, the first and the second intermediate layers being nonmagnetic. The first and the second strain sensing devices, and the barycenter are in a straight line.

Abstract: The present disclosure relates to an acoustic control apparatus applied to a loudspeaker system including first to Mth loudspeakers. In one implementation, the apparatus includes first to Mth control filters. The first to Mth control filters convolve a first input sound signal with first to Mth control filter coefficients to generate first to Mth sound signals. The first to Mth loudspeakers produce sounds based on the first to Mth sound signals. The second to Mth control filter coefficients are calculated based on the first control filter coefficient and at least one first acoustic transfer function set from the first to Mth loudspeakers to at least one first one-ear position, such that a spatial average of at least one sound pressure of the sounds at the at least one first one-ear position comes close to 0.

Abstract: According to one embodiment, a speaker system includes a plurality of filters and a plurality of speakers. The filters filter a first signal to generate a plurality of second signals. The speakers convert the second signals into respective sound waves. Each speaker has a diaphragm and a vibration source installed in the diaphragm. Diagrams of the speakers have at least two different shapes. Respective transfer characteristics of the diaphragms are different from each other. Each filter corresponding to the respective transfer characteristics is set such that a transfer characteristic of a synthetic sound wave of the respective sound waves approaches a target transfer characteristic.

Abstract: According to an embodiment, a navigation device installed in a vehicle includes an obtainer, a controller, and a reproducer. The obtainer obtains at least one of vehicle information related to the vehicle and driver information related to a driver of the vehicle. The controller controls, based on at least one of the vehicle information and the driver information, localization direction of a playback sound which is to be reproduced for the driver. The reproducer reproduces the playback sound using a three dimensional sound based on control of the localization direction.

Abstract: According to one embodiment, a pressure sensor includes a base, and a first sensor unit. The first sensor unit includes a first transducer thin film, a first strain sensing device and a second strain sensing device. The first strain sensing device includes a first magnetic layer, a second magnetic layer, and a first intermediate layer provided between the first and the second magnetic layers. The second strain sensing device is provided apart from the first strain sensing device on the first membrane surface and provided at a location different from a location of the barycenter, the second strain sensing device including a third magnetic layer, a fourth magnetic layer, and a second intermediate layer provided between the third and the fourth magnetic layers, the first and the second intermediate layers being nonmagnetic. The first and the second strain sensing devices, and the barycenter are in a straight line.

Abstract: According to an embodiment, a control filter coefficient is calculated in such a manner that a second spatial average of one or more complex sound pressure ratios at one or more target binaural positions when a first loudspeaker and a second loudspeaker emit a second acoustic signal and a first acoustic signal is approximated to a first spatial average of one or more complex sound pressure ratios at the one or more target binaural positions when a target virtual acoustic source emits the first acoustic signal.

Abstract: According to one embodiment, a noise reduction system for reducing noise including impact noise repetitively generated at a time interval includes the following elements. The error signal generator generates an error signal based on the noise being detected. The delay signal generator has a time delay characteristic and delays a signal, which is generated based on the error signal, to generate a delay signal, the time delay characteristic being determined based on an imaging sequence or pre-scanning by the MRI device and corresponding to the time interval. The control filter generates the first control signal from the delay signal. The loudspeaker unit includes at least one pair of a first filter and a control loudspeaker and a transmission unit.

Abstract: The present disclosure relates to an acoustic control apparatus applied to a loudspeaker system including first to Mth loudspeakers. In one implementation, the apparatus includes first to Mth control filters. The first to Mth control filters convolve a first input sound signal with first to Mth control filter coefficients to generate first to Mth sound signals. The first to Mth loudspeakers produce sounds based on the first to Mth sound signals. The second to Mth control filter coefficients are calculated based on the first control filter coefficient and at least one first acoustic transfer function set from the first to Mth loudspeakers to at least one first one-ear position, such that a spatial average of at least one sound pressure of the sounds at the at least one first one-ear position comes close to 0.

Abstract: According to one embodiment, an acoustic control apparatus includes an acquisition unit, a detection unit, a correction unit, and an output unit. The acquisition unit acquires a first acoustic signal. The detection unit detects an information sound. When the detection unit detects the information sound, the correction unit corrects the first acoustic signal to a second acoustic signal by convoluting the first acoustic signal with a first function. The first function represents an acoustic transfer characteristic from a virtual position to a listening position. The virtual position is located along a first direction from the listening position. The output unit outputs the second acoustic signal.

Abstract: According to an embodiment, a speaker system includes filters, speakers, and a sound collection unit. Each of the filters filters a first signal to generate a second signal. The speakers are arranged so that transfer characteristics from the speakers to an evaluation point are different from each other. Each of the speakers converts the second signal generated by a corresponding one of the filters into a sound wave. The sound collection unit combines sound waves output from the speakers to generate a combined sound wave. The filters are formed so that a transfer characteristic from the first signal to an output signal matches a target transfer characteristic, the output signal indicating a sound pressure of the combined sound wave at the evaluation point.

Abstract: According to one embodiment, an active noise-reduction apparatus includes following units. The reference signal generation unit generates different reference signals based on target sound generated from a sound source. The filter processing unit generates first control signals by filtering the reference signals using first digital filters. The averaging unit generates a second control signal by averaging the first control signals. The control speaker outputs the second control signal as control sound. The error microphone detects a synthetic sound pressure of the target sound and the control sound to generate an error signal. The filter update unit updates the first digital filters so that the error signal is minimized.

Abstract: According to one embodiment, a sound field control apparatus is provided with a control filter and a calculation unit. The filter executes an FIR computation for an acoustic signal using coefficients to output a main signal and control signals. The unit calculates the main coefficient and the coefficients based on Spatial transmission characteristics and a sound increase factor n, to set a composite sound pressure from a main speaker and control speakers to a first area to be n times of a coming sound pressure from only the main speaker, and to set a composite sound pressure from the main speaker and control speakers to a second area to be equal to the coming sound pressure from only the main speaker.

Abstract: According to one embodiment, a noise reduction system for reducing noise including impact noise repetitively generated at a time interval includes the following elements. The error signal generator generates an error signal based on the noise being detected. The delay signal generator has a time delay characteristic and delays a signal, which is generated based on the error signal, to generate a delay signal, the time delay characteristic being determined based on an imaging sequence or pre-scanning by the MRI device and corresponding to the time interval. The control filter generates the first control signal from the delay signal. The loudspeaker unit includes at least one pair of a first filter and a control loudspeaker and a transmission unit.

Abstract: According to an embodiment, a navigation device installed in a vehicle includes an obtainer, a controller, and a reproducer. The obtainer obtains at least one of vehicle information related to the vehicle and driver information related to a driver of the vehicle. The controller controls, based on at least one of the vehicle information and the driver information, localization direction of a playback sound which is to be reproduced for the driver. The reproducer reproduces the playback sound using a three dimensional sound based on control of the localization direction.

Abstract: According to an embodiment, an acoustic control apparatus applied to a loudspeaker system including first to Mth loudspeakers includes first to Mth control filters. The first to Mth control filters convolve a first input sound signal with first to Mth control filter coefficients to generate first to Mth sound signals. The first to Mth loudspeakers produce sounds based on the first to Mth sound signals. The second to Mth control filter coefficients are calculated based on the first control filter coefficient, and at least one first acoustic transfer function set from the first to Mth loudspeakers to at least one first one-ear position, so that a spatial average of at least one sound pressure of the sounds at the at least one first one-ear position comes close to 0.

Abstract: According to an embodiment, a control filter coefficient is calculated in such a manner that a second spatial average of one or more complex sound pressure ratios at one or more target binaural positions when a first loudspeaker and a second loudspeaker emit a second acoustic signal and a first acoustic signal is approximated to a first spatial average of one or more complex sound pressure ratios at the one or more target binaural positions when a target virtual acoustic source emits the first acoustic signal.