This application describes methods and apparatus for loudspeaker protection. A loudspeaker protection system (100) is described having a first frequency band-splitter (102) for splitting an input audio signal (Vin) into a plurality of audio signals (v1, v2 . . . , vn) in different respective frequency bands (ω1, ω2 . . . , ωn). A first gain block (103) is configured to apply a respective frequency band gain (g1, g2 . . . , g3) to each of the audio signals in the different respective frequency bands and a gain controller (107, 108, 109) is provided for controlling the respective band gains. A displacement modeller (104, 105) determines a plurality of displacement signals (x1, x2 . . . , xn) based on the input audio signal (Vin) and a displacement model (104a) where each displacement signal corresponds to a modelled cone displacement for the loudspeaker for one of said different respective frequency bands. The gain controller (107, 108, 109) is configured to control the respective frequency band gains based on the plurality of displacement signals.

An audio system for a headset includes a plurality of speakers and an audio controller. The plurality of speakers may be in a dipole configuration that cancel sound leakage into a local area of the headset. The controller filters audio content presented by the plurality of speakers to further mitigate leakage of audio content into the local area. The audio determines sound filters based on environmental conditions, such as ambient noise levels, as well as based on the audio content being presented.

Provided is a haptic device including a medium for receiving a digital sound signal from a portable terminal, a digital-to-analog converter (DAC) for receiving the digital sound signal from the medium and converting the digital sound signal into an analog signal, a sound outputter for receiving the analog signal and outputting sound, and a haptic actuator driven by receiving the analog signal.

A bidirectional channel control system, method, device, and non-transitory computer-readable storage medium based on Digital Enhanced Cordless Telecommunications is provided. The system comprises a transmitter, at least one receiver, an audio channel, and a text message control channel. The transmitter is configured to send an audio data stream to the at least one receiver through the audio channel. The transmitter is configured to send a control command to the one receiver through the text message control channel in a one-to-one single-point text message mode, and to receive a feedback result from the one receiver in response to the control command. Alternatively, the transmitter is configured to send a control command to each of the at least one receiver based on DECT protocol through the text message control channel in at least one of a one-to-many broadcast messaging mode and a one-to-one single-point messaging mode, and to receive a feedback result from each of the at least one receiver in response to the control command in the one-to-one single-point messaging mode.

An example method of operation may include identifying, in a particular room environment, a number of speakers and one or more microphones on a network controlled by a controller and amplifier, providing test signals to play sequentially from each amplifier channel of the amplifier and the speakers, monitoring the test signals from the one or more microphones simultaneously to detect operational speakers and amplifier channels, providing additional test signals to the speakers to determine tuning parameters, detecting the additional test signals at the one or more microphones controlled by the controller, and automatically establishing a background noise level and noise spectrum of the room environment based on the detected additional test signals.

A Bluetooth audio broadcasting system includes: an audio broadcasting device, a first Bluetooth member device, and a second Bluetooth member device. The audio broadcasting device broadcasts BLE audio packets. After the first Bluetooth member device issues a volume adjusting request, the audio broadcasting device transmits a volume adjusting instruction to the first Bluetooth member device and the second Bluetooth member device. The first Bluetooth member device acquires a predetermined audio data from the BLE audio packets, controls a first audio playback circuit to playback the predetermined audio data, and adjusts an audio volume of the first audio playback circuit according to the volume adjusting instruction. The second Bluetooth member device acquires the predetermined audio data from the BLE audio packets, controls a second audio playback circuit to playback the predetermined audio data, and adjusts an audio volume of the second audio playback circuit according to the volume adjusting instruction.

Brownout management for an audio amplification system. An audio amplification system includes audio volume control circuitry, audio sample interpolation circuitry, and brownout management circuitry. The brownout management circuitry includes brownout detection circuitry and brownout response circuitry. The brownout detection circuitry is configured to determine whether a voltage of a battery that powers the audio amplification system is below a brownout threshold, and to generate a brownout detection signal that indicates the voltage is below the brownout threshold. The brownout response circuitry is coupled to an audio output of the audio sample interpolation circuitry. The brownout response circuitry is configured to attenuate the audio samples output by the audio sample interpolation circuitry responsive to the brownout detection signal indicating that the voltage is below the brownout threshold.

Provided are, among other things, systems, methods and techniques for processing an audio signal to add virtual bass. In one representative embodiment, an apparatus includes: (a) an input line that inputs an original audio signal; (b) a bass extraction filter that extracts a bass portion of such original audio signal; (c) an estimator that estimates a fundamental frequency of a bass sound within such bass portion; (d) a frequency translator that shifts the bass portion by a positive frequency increment that is an integer multiple of the fundamental frequency estimated by the estimator, thereby providing a virtual bass signal; (f) an adder having (i) inputs coupled to the original audio signal and to the virtual bass signal and (ii) an output; and (g) an audio output device coupled to the output of the adder.

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.

Described herein is a method for improving dialogue intelligibility during playback of audio data on a playback device, wherein the audio data comprise dialogue audio data, and at least one of music and effects audio data, the method including the steps of: determining a volume mixing ratio based on a volume value for playback; mixing the dialogue audio data and the at least one of music and effects audio data based on said volume mixing ratio; and outputting the mixed audio data for playback. Described are further a respective playback device and a respective computer program product.