Devices for preventing unintended conversation from being recorded by a voice activated assistant device/application (VAD) are disclosed. The device is contoured to fit over a functional surface of a VAD that typically includes a plurality of microphones and control buttons. The device covers the microphones and uses its own microphones to monitor for an authorization input signal. In an embodiment, the devices uses speakers aligned with and opposing each VAD microphone. The device emits interfering audible signals during this mode of operation. Once the device senses an authorization input, the device decouples its speakers from the interfering audible signal and instead allows the device microphones to pass through to the VAD. During this mode, the VAD is in normal operation.

Provided is a technique to generate a call environment that prevents call contents from being heard by a person other than a person speaking on the phone in a case where call voice is output from a speaker. Speakers installed in an automobile are denoted by SP.sub.1, ..., SP.sub.N, a first filter coefficient used to generate an input signal for a speaker SP.sub.n is denoted by F.sub.n (ω), and a second filter coefficient that is different from the first filter coefficient and is used to generate an input signal for the speaker SP.sub.n is denoted by .sup.~F.sub.n (ω). A call environment generation method includes: an acoustic signal generation step of generating, when detecting a start signal of a call, a call-time acoustic signal that is obtained by adjusting volume of an acoustic signal to be reproduced during the call, by using a predetermined volume value; a first local signal generation step of generating a sound signal S.sub.n as an input signal for the speaker SP.sub.n from a voice signal of the call by using the first filter coefficient F.sub.n (ω); and a second local signal generation step of generating an acoustic signal A.sub.n as an input signal for the speaker SP.sub.n from the call-time acoustic signal by using the second filter coefficient .sup.~F.sub.n (ω).

A sound masking system according to the invention is disclosed in which one or more sound masking loudspeaker assemblies are coupled to one or more electronic sound masking signal generators. The loudspeaker assemblies in the system of the invention have a low directivity index and preferably emit an acoustic sound masking signal that has a sound masking spectrum specifically designed to provide superior sound masking in an open plan office. Each of the plurality of loudspeaker assemblies is oriented to provide the acoustic sound masking signal in a direct path into the predetermined area in which masking sound is needed. In addition, the sound masking system of the invention can include a remote control function by which a user can select from a plurality of stored sets of information for providing from a recipient loudspeaker assembly an acoustic sound masking signal having a-selected sound masking spectrum.

A system and method are provided for dynamic sound mask adjustment. A sound mask is used for obtaining an impulse response measurement that adjusts a generated sound mask dynamically based on real-time ambient noise parameters, while maintaining echo canceller calibration performance. The system includes a dynamic sound mask generator that includes a noise accumulator and monitor that includes a processor and memory including instructions executed by the processor for performing the dynamic sound mask adjustment. If the sound mask is not in the hysteresis range, the current sound mask level and iteration update rate are adjusted. if the sound mask is in the hysteresis range, the current sound mask level and iteration update rate are maintained.

In the sound insulation apparatus, a sound wave transmitter configured to transmit sound waves with frequencies including the frequencies of propagation sound waves from a sound source and a sound wave receiver configured to receive the sound waves transmitted from the sound wave transmitter are coupled such that the orientation of a sound wave transmission surface of the sound wave transmitter and the orientation of a sound wave receiving surface of the sound wave receiver intersect each other and one pair set is formed. The one pair set is disposed in plurality such that the sound wave transmission surface of one set is spaced from and opposed to the sound wave receiving surface of another set and a space surrounding the sound source is formed. The sound waves transmitted from each of the sound wave transmitters are mixed with the propagation sound waves.

A mobile terminal booth with a sound masking function includes a sound absorbing panel which partitions a space as viewed from the above to provide a place where a user of a mobile terminal can have a telephone conversation; a speaker provided to emit sounds to an outside of the mobile terminal booth; and a masking sound generation unit provided to emit a masking sound through the speaker. The harsh-sounding high frequency components of the masking sound are attenuated so that the masking sound gives less uncomfortable feeling to persons surrounding the mobile terminal booth. This masking sound is generated by attenuating a high frequency component of a raw sound material including a natural sound.

An information processing device includes a first acquisition unit that acquires biological information on a user, a first judgment execution unit that executes a first judgment on whether a first discomfort condition is satisfied or not based on first discomfort condition information specifying the first discomfort condition and the biological information, a second acquisition unit that acquires a sound signal, an acoustic feature detection unit that detects an acoustic feature based on the sound signal, a second judgment execution unit that executes a second judgment on whether a second discomfort condition is satisfied or not based on second discomfort condition information specifying the second discomfort condition and the acoustic feature, and an output judgment unit that judges whether first masking sound should be outputted or not based on a result of the first judgment and a result of the second judgment.

A masking sound adjustment method includes obtaining, in each of a plurality of frequency bands, a volume adjustment amount of a masking sound with respect to a volume of a conversation sound to be masked, based on a threshold value corresponding to a target word intelligibility of the conversation sound to be masked; and adjusting a volume of the masking sound in each of the plurality of frequency bands based on the volume adjustment amount.

A panel combination includes a panel, a directional speaker mounted to the panel, and a controller that receives a trigger signal and controls an output of the directional speaker according to the trigger signal.

A speech reproduction device for reproducing speech based on a received speech signal so that the reproduced speech is intelligible in a clear speech zone and unintelligible in a masked speech zone includes an audio processing module configured for receiving the speech signal; a set of speech loudspeakers configured for reproducing the speech based on one or more speech loudspeaker signals; and a set of masking sound loudspeakers configured for producing a masking sound based on one or more masking sound loudspeaker signals, wherein the masking sound masks the speech in the masked speech zone; wherein the audio processing module includes a speech signal analysis module configured for producing one or more analysis signals based on spectral and/or temporal characteristics of the speech signal; wherein the audio processing module includes a masking sound generator configured for producing one or more masking sound signals based on the one or more analysis signals.