Disclosed is a system configured to determine filter parameters of an audio precompensation filter for the compensation of an associated sound generating system having at least two loudspeakers. The system is configured to obtain sound field models describing the sound field in at least one region of space designated the bright zone and the sound field in at least one region of space designated the dark zone. The system is also configured to obtain a target sound field in the bright zone. Further, the system is configured to determine filter parameters of the audio precompensation filter so that a criterion function is optimized under the constraint of causality and stability of the dynamics of the audio precompensation filter to enable reproduction of a desired target sound field in the bright zone, while reproducing as little sound as possible in the dark zone.

A gain control system for controlling gain applied to an audio signal includes a power estimator configured to estimate the power of a digital signal derived from the audio signal, a digital gain estimator configured to determine, in dependence on the estimated power, a digital gain which would modify the power of the digital signal so as to reach a target power level, and a gain controller configured to adjust an analogue gain applied to the audio signal in dependence on the determined digital gain.

In an audio encoder, for audio content received in a source audio format, default gains are generated based on a default dynamic range compression (DRC) curve, and non-default gains are generated for a non-default gain profile. Based on the default gains and non-default gains, differential gains are generated. An audio signal comprising the audio content, the default DRC curve, and differential gains is generated. In an audio decoder, the default DRC curve and the differential gains are identified from the audio signal. Default gains are re-generated based on the default DRC curve. Based on the combination of the re-generated default gains and the differential gains, operations are performed on the audio content extracted from the audio signal.

A multi-path subsystem may include a first processing path, a second processing path, a mixed signal return path, and a calibration engine configured to: estimate and cancel a direct current (DC) offset of the mixed signal return path, estimate and cancel a DC offset between the first processing path and the second processing path, estimate and cancel a phase difference between the first processing path and a sum of the second processing path and the mixed signal return path, estimate and cancel a return path gain of the mixed signal return path, and track and correct for a gain difference between the first processing path and the second processing path.

This invention provides compact Power Amplifiers with improved efficiency of the circuitry and improved heat dissipation, together achieved much smaller enclosure size for use in modern installations requiring reduced height such as between the thin flat TV and wall, under the table or on the projector pole or in ceiling box and the like.

An audio signal processing circuit includes a filter, a gain control circuit, and a bass boost circuit. The filter filters an audio signal and produces a filtered signal accordingly. The gain control circuit divides the filtered signal in the time domain into a first segment and a second segment that are substantially equal in length, measures a first amplitude of the first segment and a second amplitude of the second segment, and generates a gain based on the first amplitude which is greater than the second amplitude. The bass boost circuit adjusts the amplitudes of the first segment and the second segment according to the gain.

An audio mixer includes a user interface, panners, a first adder, a localization device, a second adder, and an output circuit. The user interface supplies a first parameter and a second parameter for each channel based on a user operation. The first parameter indicates a position in a right-left direction. The second parameter specifies internalization or externalization. The panners respectively correspond to channels and, based on the first parameter, pan a sound signal corresponding to the each channel to generate first stereo signals. The first adder generates a second stereo signal by mixing first stereo signals respectively corresponding to externalization channels. The localization device generates two third stereo signals. The second adder generates a fourth stereo signal by mixing the two third stereo signals and first stereo signals respectively corresponding to internalization channels. The output circuit outputs the fourth stereo signal.

Example techniques may provide volume enhancements to a media playback system. An example implementation involves a first playback device in a first playback configuration playing audio at a first volume level and storing the first volume level in association with the first playback configuration. The first playback device receives instructions to change to a second playback configuration. Based on receiving the instructions, the first playback device joins a synchrony group with a second zone and adjusts the first playback device to play audio at a second volume level which is based on a volume level of a second playback device in the second zone. While in the second playback configuration, the first playback device receives instructions to change to the first playback configuration and, based on the instructions, leaves the synchrony group and adjusts the first playback device to play audio content at the stored first volume level.

Techniques for optimizing a player based on the addition of a second player are disclosed. In an embodiment, when a first player no longer needs to play certain audio frequencies due to the addition of a second player, the gain of the first player is automatically increased as part of the setup process. In another embodiment, when a first player needs to play certain audio frequencies, for example due to the removal of a second player, the gain of the first player is automatically decreased. Many other embodiments are disclosed.

A method and an electronic device of controlling an audio output are disclosed. The method includes detecting an audio output device connected to an electronic device, determining a type of audio output device associated with the audio output device connected to the electronic device, determining a first audio output level associated with the audio output device connected to the electronic device based on the type of audio output device and a predetermined audio output level, and outputting an audio output at the first audio output level using the audio output device.