Example techniques involve calibration of one or more playback devices. An example implementation involves a playback device playing back audio content using a first calibration via the one or more audio transducers and the one or more amplifiers. The first calibration is based on a response of a listening environment to audio content playback by the playback device. The playback device records, via one or more microphones, at least a portion of the played back audio content. Based on the recorded audio content, the playback device detects a change in the response of the listening environment to audio content playback by the playback device. Responsive to detecting the change in the response, the playback device causes output of a prompt to initiate a calibration procedure for the playback device. The calibration procedure involves a mobile device recording playback by the playback device.

Embodiments relate to binaural spatialization of more than two sound sources on two audio channels of an audio system. Sound signals each emitted from a corresponding sound source are collected, and a respective virtual position within an angular range of a sound scene is assigned to each sound source. Multi-source audio signals are generated by panning each sound signal according to the respective virtual position. A first multi-source audio signal is spatialized to a first direction to generate a first left signal and a first right signal. A second multi-source audio signal is spatialized to a second direction to generate a second left signal and a second right signal. A binaural signal is generated using the first left signal, the second left signal, the first right signal, and the second right signal. The binaural signal is such that each sound source appears to originate from its respective virtual position.

Example systems, devices, media, and methods are described for efficiently processing an audio track of a virtual object with a head-related transfer function (HRTF). Audio tracks are processed by determining a current position (direction and optionally distance) of the virtual object with respect to the head of a user, identifying a current audio zone from predefined audio zones responsive to the determined current position where each of the audio zones has a corresponding left predefined filter and a corresponding right predefined filter, applying the left and the right predefined filters corresponding to the current audio zone to the audio track to produce a left audio signal and a right audio signal, and presenting the left audio signal with a first speaker and the right audio signal with a second speaker.

A sound signal processing device includes: a vocal remover which generates a first output signal based on first-channel and second-channel sound signals and a first coefficient indicating a vocal bandwidth to be removed; a surround sound processor which generates a second output signal by adding a surround sound effect to the first output signal; an amplifier which amplifies a signal at an amplification factor that is based on a second coefficient; a synthesizer which synthesizes the second output signal with one of the first-channel and second-channel sound signals, and synthesizes a signal that is the second output signal inverted with another one of the first-channel and second-channel sound signals; and a coefficient determination unit which sets the second coefficient such that the amplification factor, used when the vocal bandwidth to be removed is greater than a first bandwidth, is greater than the amplification factor for the first bandwidth.

Wireless headphones with battery life effectively extended includes first and second headphones. The first and second headphones each with respective low battery levels remaining or very different battery levels remaining receive audio signals from an electronic device and output the sound of the audio signal after adjustments are applied to volume level and to sound quality on one side or on both sides, to reduce the consumption of battery level. Each of the first and second headphones carries a processor for intercommunication in addition to communication with the electronic device performing playback.

Embodiments included herein generally relate to using non-audio data embedded in an audio signal. More particularly, embodiments relate to using non-audio data embedded into the audio signal to control an audio configuration of a plurality of speakers and/or to measure a delay of a playback device.

This application relates to audio driving circuitry (100), and in particular to audio driving circuitry for outputting first and second audio driving signals for driving a stereo audio load (106), which may be a stereo audio load of an accessory apparatus (102) removably coupled to the audio driving circuitry in use. A load monitor (111) is provided for monitoring to monitor, from a monitoring node (112), an indication of a common mode return current passing through a common return path, together with an indication of a common mode component of the first and second audio driving signals and to determine an impedance characteristic of the stereo audio load. The load monitor (111) can provide dynamic monitoring of any significant change in load impedance. In some embodiments the load monitor (111) comprises an adaptive filter (301) which adapts a parameter of the filter which is related to the load impedance so as to determine the indication of load impedance.

An apparatus for downmixing a multi-channel signal having at least two channels, has: a downmixer for calculating a downmix signal from the multi-channel signal, wherein the downmixer is configured to calculate the downmix using an absolute phase compensation, so that a channel having a lower energy among the at least two channels is only rotated or is rotated stronger than a channel having a greater energy in calculating the downmix signal; and an output interface for generating an output signal, the output signal having information on the downmix signal.

Generating, rendering and outputting one or more audio signals that have one or more audio sequences and/or spectral modulations of an audio file including a plurality of audio-based user prompts in an audio interference processing system. An audio interference processing system and method incudes initiating an instance of an audio interference processing session, configuring one or more session parameters, rendering/outputting a training audio output to one or more transducers, rendering/outputting one or more audio discrimination and audio navigation signals to the one or more transducers, receiving two or more sensor inputs in response to rendering/outputting one or more audio discrimination and audio navigation signals to the one or more transducers, processing the two or more sensor inputs, and providing a feedback output to a user via one or more modalities.

An apparatus comprising a mapper configured to map an instance of a parameter according to a first mapping to generate a first mapped instance; a remapper configured to remap the first mapped instance dependent on the frequency distribution of mapped instances to generate a remapped instance with an associated order position; and an encoder configured to encode the remapped instance dependent on an order position of the remapped instance.