Abstract: A sound amplification apparatus includes one or more microphones that convert collected sound into an audio signal and transmit the audio signal by radio and a sound receiving apparatus that receives the audio signal transmitted from the microphone and amplifies and outputs the sound based on the audio signal. The sound receiving apparatus is configured to perform sound output control in an emergency mode upon receiving an emergency signal transmitted in response to operation of an emergency switch of the microphone. With this configuration, it is possible to perform appropriate sound control in a dangerous situation such as intrusion of a suspicious person.

Abstract: A sound amplification apparatus includes one or more microphones that convert collected sound into an audio signal and transmit the audio signal by radio and a sound receiving apparatus that receives the audio signal transmitted from the microphone and amplifies and outputs the sound based on the audio signal. The sound receiving apparatus is configured to perform sound output control in an emergency mode upon receiving an emergency signal transmitted in response to operation of an emergency switch of the microphone. With this configuration, it is possible to perform appropriate sound control in a dangerous situation such as intrusion of a suspicious person.

Abstract: A sound amplification apparatus includes one or more microphones that convert collected sound into an audio signal and transmit the audio signal by radio and a sound receiving apparatus that receives the audio signal transmitted from the microphone and amplifies and outputs the sound based on the audio signal. The sound receiving apparatus is configured to perform sound output control in an emergency mode upon receiving an emergency signal transmitted in response to operation of an emergency switch of the microphone. With this configuration, it is possible to perform appropriate sound control in a dangerous situation such as intrusion of a suspicious person.

Abstract: A sound amplification apparatus (10) comprises one or more microphones (11) that convert collected sound into an audio signal and transmit the audio signal by radio and a sound receiving apparatus (13) that receives the audio signal transmitted from the microphone (11) and amplifies and outputs the sound based on the audio signal. The sound receiving apparatus (13) is configured to perform sound output control in an emergency mode upon receiving an emergency signal transmitted in response to operation of an emergency switch (12) of the microphone (11). With this configuration, it is possible to perform appropriate sound control in a dangerous situation such as intrusion of a suspicious person.

Abstract: A sound amplification apparatus includes one or more microphones that convert collected sound into an audio signal and transmit the audio signal by radio and a sound receiving apparatus that receives the audio signal transmitted from the microphone and amplifies and outputs the sound based on the audio signal. The sound receiving apparatus is configured to perform sound output control in an emergency mode upon receiving an emergency signal transmitted in response to operation of an emergency switch of the microphone. With this configuration, it is possible to perform appropriate sound control in a dangerous situation such as intrusion of a suspicious person.

Abstract: An acoustic feedback suppression apparatus includes an amplitude measurement section for measuring the amplitude of a sound signal input from a microphone, an amplitude attenuation section for attenuating the amplitude of a sound signal output to a speaker, and an acoustic feedback determination section for determining whether or not acoustic feedback is occurring based on the sound signal input from the microphone. If it is determined that acoustic feedback is occurring, a sound-deadening control section enables sound-deadening control so that the amplitude of the sound signal output to the speaker is attenuated to a sound-deadening level. A sound-deadening release section releases the sound-deadening control if the amplitude of the sound signal input from the microphone is more than specified threshold amplitude and if it is determined that acoustic feedback is not occurring while the sound-deadening control is conducted.

Abstract: An acoustic feedback suppression apparatus includes an amplitude measurement section for measuring the amplitude of a sound signal input from a microphone, an amplitude attenuation section for attenuating the amplitude of a sound signal output to a speaker, and an acoustic feedback determination section for determining whether or not acoustic feedback is occurring based on the sound signal input from the microphone. If it is determined that acoustic feedback is occurring, a sound-deadening control section enables sound-deadening control so that the amplitude of the sound signal output to the speaker is attenuated to a sound-deadening level. A sound-deadening release section releases the sound-deadening control if the amplitude of the sound signal input from the microphone is more than specified threshold amplitude and if it is determined that acoustic feedback is not occurring while the sound-deadening control is conducted.

Abstract: The present invention provides a communication system. When the audio signal in the wide band is input to a wireless microphone, the wireless microphone performs a balanced modulation processing to invert the frequency spectrum of the audio signal and transmits the audio signal with the inverted frequency. When a speaker apparatus receives the audio signal transmitted from the wireless microphone, the speaker apparatus cuts off a frequency component of the received audio signal in the frequency band of the infrared radiation noise produced by the external apparatus (infrared radiation noise band), performs a reverse balanced modulation processing to invert again the frequency spectrum of the audio signal having the frequency component in the infrared radiation noise band cut off, and outputs the audio signal with the frequency spectrum inverted again.

Abstract: A sound amplification apparatus (10) comprises one or more microphones (11) that convert collected sound into an audio signal and transmit the audio signal by radio and a sound receiving apparatus (13) that receives the audio signal transmitted from the microphone (11) and amplifies and outputs the sound based on the audio signal. The sound receiving apparatus (13) is configured to perform sound output control in an emergency mode upon receiving an emergency signal transmitted in response to operation of an emergency switch (12) of the microphone (11). With this configuration, it is possible to perform appropriate sound control in a dangerous situation such as intrusion of a suspicious person.

Abstract: A wireless microphone transmits audio signals using infrared rays. A plurality of infrared light emitting devices are attached to a board in the wireless microphone, and at least one of the plurality of infrared light emitting devices is disposed on each side of the board. A plurality of infrared light emitting devices may be provided on each side of the board, and the infrared light emitting devices may be disposed radially. Without providing a different dedicated board for the light emitting devices than the board, infrared rays can be radiated to an area around the mic. In this manner, a wireless microphone is provided that can radiate infrared rays to an area around the mic and that has a simple structure and a small number of components and thus can improve productivity.

Abstract: A digital signal receiving apparatus which can automatically determine the transmission format of a digital audio signal based on AES3, and then simplify the operations, avoid wrong operations at times of switching, and prevent errors in the transmission format due to wrong operations. In this apparatus, a channel status FS detection section 109 detects the sampling frequency of an input digital audio signal based on AES3, a transmission rate detection section 111 detects the transmission rate of the input digital audio signal based on AES3. A control section 113 determines the transmission format of the input digital audio signal based on AES3, based on both detected results (sampling frequency and transmission rate).