Abstract: A display device includes a display panel, an actuator that comes into contact with a back surface of the display panel, and a woofer configured to generate a sound wave from behind the display panel toward the back surface of the display panel.

Abstract: A display apparatus according to an embodiment of the present disclosure includes a thin plate-shaped display cell that displays image and a plurality of exciters disposed on a back surface of the display cell and causing the display cell to vibrate. The plurality of exciters is such configured that the plurality of exciters is regarded as one exciter when the plurality of exciters generates vibration in the display cell.

Abstract: A display apparatus according to an embodiment of the present disclosure includes a thin plate-shaped display cell that displays image and a plurality of exciters disposed on a back surface of the display cell and causing the display cell to vibrate. The plurality of exciters is such configured that the plurality of exciters is regarded as one exciter when the plurality of exciters generates vibration in the display cell.

Abstract: A flat panel speaker according to an embodiment of the disclosure includes a flat panel and a plurality of vibrators that are disposed on a back surface of the flat panel. The plurality of vibrators are disposed to avoid a location that most easily vibrates in an entire range of audio frequencies when vibration is generated in the flat panel by the plurality of vibrators. A large stationary wave with respect to the flat panel therefore does not easily occur.

Abstract: A display apparatus according to an embodiment of the present disclosure includes a thin plate-shaped display cell that displays image and a plurality of exciters disposed on a back surface of the display cell and causing the display cell to vibrate. The plurality of exciters is such configured that the plurality of exciters is regarded as one exciter when the plurality of exciters generates vibration in the display cell.

Abstract: A display apparatus according to an embodiment of the present disclosure includes a thin plate-shaped display cell that displays image and a plurality of exciters disposed on a back surface of the display cell and causing the display cell to vibrate. The plurality of exciters is such configured that the plurality of exciters is regarded as one exciter when the plurality of exciters generates vibration in the display cell.

Abstract: A flat panel speaker according to an embodiment of the disclosure includes a flat panel and a plurality of vibrators that are disposed on a back surface of the flat panel. The plurality of vibrators are disposed to avoid a location that most easily vibrates in an entire range of audio frequencies when vibration is generated in the flat panel by the plurality of vibrators. A large stationary wave with respect to the flat panel therefore does not easily occur.

Abstract: A signal amplification apparatus which supplies an input signal to a signal processing section to perform signal processing on the input signal, amplifies a power supply voltage supplied from a power source section in accordance with the processed signal, and outputs the amplified power supply voltage. The apparatus includes output decrease prediction means for predicting decrease of the output signal on the basis of an amplitude of the input signal; power supply voltage correction signal generation means for generating a power supply voltage correction signal for correcting the power supply voltage of the power source section on the basis of the predicted decrease of the output signal; and feedforward control means for performing feedforward control of the power supply voltage of the power source section by using the power supply voltage correction signal.

Abstract: A digital amplifier apparatus includes a gain-adjusting section operable to adjust a gain of a digital audio signal; a dither-superposing section operable to superpose a predetermined dither on the digital audio signal; a pulse-width-modulated signal generating section operable to generate a pulse-width-modulated signal corresponding to the digital audio signal; an amplifying section operable to cause a switching element to perform a switching operation in accordance with the pulse-width-modulated signal; a pulse-width changing section operable to change a ratio between a “high” state and a “low” state of the pulse-width modulated signal; a synchronizing section operable to synchronize the pulse-width modulated signal with a reset signal that resets the digital audio signal; and a control section operable to perform a resetting operation by setting the gain of the digital audio signal to a zero level upon receiving the reset signal, stopping the superposing of the dither to thereby generate the pulse-width mo

Abstract: A digital amplifier apparatus includes a gain-adjusting section operable to adjust a gain of a digital audio signal; a dither-superposing section operable to superpose a predetermined dither on the digital audio signal; a pulse-width-modulated signal generating section operable to generate a pulse-width-modulated signal corresponding to the digital audio signal; an amplifying section operable to cause a switching element to perform a switching operation in accordance with the pulse-width-modulated signal; a pulse-width changing section operable to change a ratio between a “high” state and a “low” state of the pulse-width modulated signal; and a control section operable to perform a muting process by causing the gain-adjusting section to set the gain of the digital audio signal to a zero level, the dither-superposing section to stop superposing the dither, and the pulse-width changing section to change, step by step, the ratio between the “high” state and the “low” state of the pulse-width modulated signal tow

Abstract: A power amplifier apparatus includes a dither superimposing unit superimposing DC dither on a digital signal; a switching signal generating unit converting the digital signal on which the DC dither is superimposed by the dither superimposing unit to a pair of drive pulses on high and low sides having opposite levels; and a cancel signal generating unit generating a cancel signal to cancel a DC component caused by the DC dither by changing a ratio of pulse widths of the drive pulses on the high and low sides generated by the switching signal generating unit.

Abstract: A digital amplifier apparatus includes a gain-adjusting section operable to adjust a gain of a digital audio signal; a dither-superposing section operable to superpose a predetermined dither on the digital audio signal; a pulse-width-modulated signal generating section operable to generate a pulse-width-modulated signal corresponding to the digital audio signal; an amplifying section operable to cause a switching element to perform a switching operation in accordance with the pulse-width-modulated signal; a pulse-width changing section operable to change a ratio between a “high” state and a “low” state of the pulse-width modulated signal; and a control section operable to perform a muting process by causing the gain-adjusting section to set the gain of the digital audio signal to a zero level, the dither-superposing section to stop superposing the dither, and the pulse-width changing section to change, step by step, the ratio between the “high” state and the “low” state of the pulse-width modulated signal tow

Abstract: A digital amplifier apparatus includes a gain-adjusting section operable to adjust a gain of a digital audio signal; a dither-superposing section operable to superpose a predetermined dither on the digital audio signal; a pulse-width-modulated signal generating section operable to generate a pulse-width-modulated signal corresponding to the digital audio signal; an amplifying section operable to cause a switching element to perform a switching operation in accordance with the pulse-width-modulated signal; a pulse-width changing section operable to change a ratio between a “high” state and a “low” state of the pulse-width modulated signal; a synchronizing section operable to synchronize the pulse-width modulated signal with a reset signal that resets the digital audio signal; and a control section operable to perform a resetting operation by setting the gain of the digital audio signal to a zero level upon receiving the reset signal, stopping the superposing of the dither to thereby generate the pulse-width mo

Abstract: A sound field correction apparatus that corrects a sound field characteristic by supplying a measurement signal used for measurement purposes to drive a plurality of speakers arranged at arbitrary positions to reproduce the measurement signal and receiving a collected sound signal obtained by collecting the sound reproduced from the plurality of speakers with a sound collector disposed at an arbitrary listening point is disclosed. The sound field correction apparatus includes: a measurement signal supplier, a receiver, a delay calculator, a sound pressure level difference calculator, a delay correction value calculator, and a gain correction value calculator.

Abstract: A D/A converter in which distortion caused by PWM is favorably removed even if a sampling frequency is low relative to a signal frequency is provided. The D/A converter includes a pulse-width-modulated-signal outputting circuit for outputting a pulse-width-modulated signal having a pulse width in accordance with a digital value of an input digital signal.

Abstract: In an audio amplifier having a D-class power amplifier, a noise upon muting is suppressed. A sampling rate converter circuit for sampling rate converting a digital audio signal into a digital audio signal, and a ?? modulation circuit for re-quantizing the digital audio signal into a bit-reduced digital audio signal are provided. Further, a PWM modulation circuit for converting the digital audio signal into a PWM signal, and a D-class power amplifier to which the PWM signal are supplied. Still further, a dither signal forming circuit for superimposing a dither signal SDI on the digital audio signal, and a forming circuit for forming a muting signal SDET are provided. Upon muting, an input side of the sampling rate converter circuit is stopped by the muting signal SDET.

Abstract: A signal amplification apparatus which supplies an input signal to a signal processing section to perform signal processing on the input signal, amplifies a power supply voltage supplied from a power source section in accordance with the processed signal, and outputs the amplified power supply voltage. The apparatus includes output decrease prediction means for predicting decrease of the output signal on the basis of an amplitude of the input signal; power supply voltage correction signal generation means for generating a power supply voltage correction signal for correcting the power supply voltage of the power source section on the basis of the predicted decrease of the output signal; and feedforward control means for performing feedforward control of the power supply voltage of the power source section by using the power supply voltage correction signal.

Abstract: A class D power amplifier (1) switches a power supply voltage VDD at high-speed in response to an input digital audio signal Pin to power-amplify the digital audio signal Pin, and supplies a speaker (2) with the amplified signal. In the case of being incorporated in an AM receiver formed integrally with an AM tuner (3) for receiving AM broadcasts, the class D power amplifier (1) can reduces influence of reception interference with respect to the AM tuner (3). As a result, it is possible to provide a power amplifier that can suppress unnecessary radiation to reduce reception interference with respect to the tuner, not by changing a carrier frequency, but by controlling the drive signal generation systems.

Abstract: A power amplifier apparatus includes a dither superimposing unit superimposing DC dither on a digital signal; a switching signal generating unit converting the digital signal on which the DC dither is superimposed by the dither superimposing unit to a pair of drive pulses on high and low sides having opposite levels; and a cancel signal generating unit generating a cancel signal to cancel a DC component caused by the DC dither by changing a ratio of pulse widths of the drive pulses on the high and low sides generated by the switching signal generating unit.

Abstract: In an audio amplifier having a D-class power amplifier, a noise upon muting is suppressed. There are provided a sampling rate converter circuit 23 for sampling rate converting a digital audio signal S11 into a digital audio signal S23, and a ?? modulation circuit 14 for re-quantizing the digital audio signal S23 into a bit-reduced digital audio signal S14. Further, there are provided a PWM modulation circuit 15 for converting the digital audio signal S14 into a PWM signal S15, and a D-class power amplifier 16 to which the PWM signal S15 is supplied. Still further, there are provided a dither signal forming circuit 18 for superimposing a dither signal SDI on the digital audio signal S23, and a forming circuit 19 for forming a muting signal SDET. Upon muting, an input side of the sampling rate converter circuit 23 is stopped by the muting signal SDET.