Abstract: A method for estimating an acoustic influence of walls of a room, comprising emitting a known excitation sound signal, receiving a set of measurement signals, each measurement signal being received by one microphone in a microphone array and each measurement signal including a set of echoes caused by reflections by the walls, solving a linear system of equations to identify locations of image source and estimating the acoustic influence based these image sources. The signal model includes a convolution of: the excitation signal, a multichannel filter (M) representing the relative delays of the microphones in the microphone array, the relative delays determined based on a known geometry of the microphone array, and a directivity model ?(n, p) of the driver(s) in the form of an anechoic far-field impulse response as a function of transmit angle.

Abstract: Methods and devices for repelling mosquitoes may operate by generating the sounds of fore and hind pairs of dragonfly wings, which may be dragonfly wing beat sounds. Such sounds may be generated using digital or analog circuitry. The digital sounds may be recordings of synthesized or enhanced sounds of dragonfly wings beating. The device may take the form of a button that may be worn or otherwise carried by a user.

Abstract: A method of extracting a fundamental frequency of an input sound includes generating a DJ transform spectrogram indicating estimated pure-tone amplitudes for respective natural frequencies of a plurality of springs and a plurality of time points by calculating the estimated pure-tone amplitudes for the respective natural frequencies by modeling an oscillation motion of the plurality of springs having different natural frequencies with respect to an input sound, calculating degrees of fundamental frequency suitability based on a moving average of the estimated pure-tone amplitudes or on a moving standard deviation of the estimated pure-tone amplitudes with respect to each natural frequency of the DJ transform spectrogram, and extracting a fundamental frequency based on local maximum values of the degrees of fundamental frequency suitability for the respective natural frequencies at each of the plurality of time points.

Abstract: Methods, systems and computer program products are provided for determining acoustic feature vectors of query and target items in a first vector space, and mapping the acoustic feature vectors to a second vector space having a lower dimension. The distribution of vectors in the second vector space can then be used to identify items from the same songs, and/or items that are complementary. A mapping function is trained using a machine learning algorithm, such that complementary audio items are closer in the second vector space than the first, according to a given distance metric.

Abstract: A method and apparatus for performing binaural rendering of an audio signal are provided. The method includes identifying an input signal that is based on an object, and metadata that includes distance information indicating a distance to the object, generating a binaural filter that is based on the metadata, using a binaural room impulse response, obtaining a binaural filter to which a low-pass filter (LPF) is applied, using a frequency response control that is based on the distance information, and generating a binaural-rendered output signal by performing a convolution of the input signal and the binaural filter to which the LPF is applied.

Abstract: An ANC system is provided, including an AD converter performing an AD conversion on an external noise signal; an ANC signal generator generating an ANC signal for canceling a noise component arriving at ears of a user based on an output signal of the AD converter; a level detector detecting a level of the output signal and causes the ANC signal generator to power down in response to the level; and a zero-cross detector detecting a zero-cross timing of the ANC signal. The level detector starts measuring a time when the level is equal to or less than a first threshold value, and causes the ANC signal generator to perform a power down operation when the zero-cross timing is detected after the measured time exceeds the predetermined value, and causes the ANC signal generator to exit from the power down operation when the level exceeds a second threshold value.

Abstract: Some methods involve receiving an input audio signal that includes N input audio channels, the input audio signal representing a first soundfield format having a first soundfield format resolution, N being an integer ?2. A first decorrelation process may be applied to two or more of the input audio channels to produce a first set of decorrelated channels, the first decorrelation process maintaining an inter-channel correlation of the set of input audio channels. A first modulation process may be applied to the first set of decorrelated channels to produce a first set of decorrelated and modulated output channels. The first set of decorrelated and modulated output channels may be combined with two or more undecorrelated output channels to produce an output audio signal that includes O output audio channels representing a second and relatively higher-resolution soundfield format than the first soundfield format, O being an integer ?3.

Abstract: A first device includes one or more processors and memory storing one or more programs configured to be executed by the one or more processors. The one or more programs include instructions for receiving, from a second device, audio mix information for a first audio item and receiving, from the second device, an indication that the first audio item is to be mixed with a second audio item distinct from the first audio item. In response to the indication, the one or more programs include instructions for transmitting to the second device an audio stream including the first audio item and the second audio item mixed in accordance with the audio mix information.

Abstract: This application relates an activity detector (100) for detecting signal activity in an input audio signal (SIN), such as may be used for always-on speech detection. The activity detector has a first time-encoding modulator (TEM) 101 including a first hysteretic comparator (201) for generating a PWM (pulse-width modulation) signal based on the input audio signal. A second TEM (103) having a second hysteretic comparator (401) is arranged to receive a reference voltage (VMID) and generate a clock signal (SCLK). A time-decoding converter (102) receives the clock signal and generates count values of a number of cycles of the clock signal in periods defined by the PWM signal. An activity monitor (104) is responsive to a count signal (SCT) from the TDC 102 to determine whether the input audio signal comprises signal activity above a defined threshold.

Abstract: A speaker system uses destructive wave interference to generate “dead spots” with respect to an audio presentation. The signal for the dead spot generating device can be an inverted signal generated using the audio signal. In one embodiment, the inverted signal is generated using the audio signal, an indication of loudness at one or more active speakers, and a determination of the characteristics of the sound path from the one or more active speakers (including delay and attenuation).

Abstract: A computer-based method for reproducing a sound quality in a performance space is provided. The method includes accessing a multi-dimensional sound signature, stored in a computer, for an audience location in a first performance space. The method further includes receiving sound data from a sound input device in a second performance space. The method further includes modifying the sound data to match a sound characteristic of the multi-dimensional sound signature. The method further includes transmitting the modified sound data through a sound output device in the second performance space.

Abstract: Ambient noise attenuating headphones are disclosed that may be used when a user is laying down on their side. The headphones include an ergonomic support structure, a noise attenuating structure housed within the ergonomic support structure having a circumferential end configured to surround an ear of the user, wherein the noise attenuating structure comprises a first and second elastic portion, and wherein the second elastic portion has the circumferential end having a material density less than the first elastic portion, and a speaker coupled to the noise attenuating structure.

Abstract: Embodiments include a method and noise cancelling system for cancelling noise in a vehicle by operating at least one noise cancelling means in a first mode of operation to output a noise cancelling signal; receiving at least one input indicative of a state of the vehicle; determining if noise cancelling error conditions are present based on the at least one received input indicative of a state of the vehicle; and operating at least one noise cancelling means in a second mode of operation if noise cancelling error conditions are determined as present.

Abstract: Synthesizing engine sound in a cabin of a vehicle includes generating a synthesized engine noise audio signal including a plurality of engine order outputs; mixing the engine order outputs in accordance with a first set of gain levels to provide a first channel output; mixing the engine order outputs in accordance with a second set of gain levels to provide a second channel output; using a first localization filter set to provide a first localized output to localize the first channel output as a first sound image at a first location within the cabin, and a second localization filter set to provide a second localized output to localize the second channel output as a second sound image at a second location within the cabin; and mixing the first and second localized outputs into loudspeaker outputs to be applied to the loudspeakers in the cabin.

Abstract: This disclosure describes an apparatus and method of an embodiment of an invention that is a conferencing device that includes a microphone array that further comprises a plurality of microphones; a processor configured to execute the following steps: performing a beamforming operation to combine the plurality of microphones into a plurality of combined signals that is greater in number than one and less in number than the plurality of microphone signals, each of the plurality of combined signals corresponding to a different fixed beam; wherein performing the beamforming operation includes applying beamforming weights to the signals from each microphone to achieve a desired pickup pattern that includes a main lobe and sidelobes together with nulls for each fixed beam; performing an acoustic echo cancellation operation generate a plurality of combined echo cancelled signals; and selecting one or more of the combined echo cancelled signals for transmission to the far end.

Abstract: An amplification system with an output driver stage for providing an output signal to acoustic output transducers such as speakers or haptic output devices removes signal distortion caused by output stage non-linearities by pre-distorting an input signal. The system includes the output driver stage, an input stage for receiving the input signal, and a processing block that receives the input signal and provides an output signal to the output driver stage. The processing block includes a pre-distortion circuit that applies a pre-distortion function to the input signal to generate the output signal if a signal level of the input signal is greater than a threshold amplitude, and if the signal level is less than or equal to the threshold amplitude, generates the output signal from the input signal by bypassing the pre-distortion circuit.

Abstract: Various implementations include systems for processing microphone audio signals for a wearable audio device. In particular implementations, a method for processing signals includes: capturing an internal signal with an inner microphone configured to be acoustically coupled to an environment inside an ear canal of a user; extracting a low frequency audio signal from the internal signal; capturing an external signal with an external microphone configured to be acoustically coupled to an environment outside the ear canal of the user; extracting a high frequency audio signal from the external signal; and mixing the high frequency audio signal with the low frequency audio signal.

Abstract: According to one embodiment, a sound emitting apparatus includes an elastic member, three or more excitation actuators, and a control circuit. The elastic member has an annular shape. The excitation actuators are arranged at a predetermined angular interval on the elastic member and are configured to apply vibration to the elastic member. The control circuit is configured to generate drive signals for driving the three or more excitation actuators. There is a phase difference between drive signals for two excitation actuators separated by the predetermined angular interval, the phase difference depending on an order of a Lobe mode being a vibration mode excited on the elastic member and the predetermined angular interval.

Abstract: Playback devices such as headphone devices can include an earpiece configured to be positioned adjacent a user's ear. The earpiece can include a transducer having a diaphragm configured to face toward the user's ear when the earpiece is positioned adjacent the user's ear, as well as an outlet vent in fluid communication with the transducer and a microphone. A support member within the earpiece includes a first opening aligned with the microphone and a second opening aligned with the outlet vent. An acoustic mesh extends over the first opening and the second opening, wherein the mesh has a substantially uniform acoustic impedance.

Abstract: Example techniques relate to playback based on acoustic signals in a system including a first network device and a second network device. A first network device may detect a presence of a user using a camera and/or infrared sensors. The first network device sends, in response to detecting the presence of the user, a particular signal via the first network interface. The second network device receives data corresponding to the particular signal and plays back an audio output corresponding to the particular signal.