Abstract: An example implementation involves a media playback system that includes one or more playback devices that are controllable by the mobile device while the mobile device is joined to the media playback system. The mobile device may join the media playback system over one or more communication paths via a cellular network from the mobile device to the media playback system. The example implementation may involve detecting that the mobile device is outside of a threshold proximity to the media playback system while the mobile device is joined to the media playback system. Based on detecting that the mobile device is outside of the threshold proximity to the media playback system, the mobile device may disconnect from the media playback system.

Abstract: In one aspect, a network microphone device includes a plurality of microphones and is configured to detect sound via the one or more microphones. The network microphone device may capture sound data based on the detected sound in a first buffer, and capture metadata associated with the detected sound in a second buffer. The network microphone device may classify one or more noises in the detected sound and cause the network microphone device to perform an action based on the classification of the respective one or more noises.

Abstract: Disclosed herein are computing devices, including playback devices, that are configured to facilitate re-joining of playback and other devices to a bonded zone based on the specific context relating to how the playback and other devices previously left the bonded zone. The computing devices may determine that playback devices that had been previously bonded in the bonded zone are now capable of communicating with each other again. The computing devices may proceed to identify how and/or why the playback devices previously left the bonded zone. Based on how and/or why the playback devices previously left the bonded zone, the computing devices may determine whether one or more of the playback devices should re-join the bonded zone. For playback devices to be re-joined to the bonded zone, the computing devices may determine audio content to be played back by one or more playback devices of the bonded zone.

Abstract: Audio device transducers are disclosed herein. In some embodiments, the audio device transducer comprises a coil, first and second terminals each disposed adjacent a first side of the coil, and first and second conductors each electrically coupled to the coil. The first conductor extends from the first end of the coil to the first terminal, and the second end extends from a second end of the coil to the second terminal. The second conductor includes a first conductive pathway and a second conductive pathway spaced apart from the first conductive pathway such that the coil is disposed between the first conductive pathway and the second conductive pathway. In some embodiments, the first conductive pathway is symmetric to the second conductive pathway about an axis extending through the coil.

Abstract: Example techniques relate to playback queue subscriptions. An example implementation involves a computing system receiving, from a first computing device associated with a first user account, an instruction to enable subscription to a first playback queue associated with a first media playback system. In response to the instruction, the computing system enables second user accounts to subscribe to the first playback queue. The second user accounts are registered with respective second media playback systems in respective second household. The computing system receives, from a particular second media playback system, a request to subscribe to the first playback queue; and in response, sends one or more messages that update a control interface of the first control device to display a subscriber indication and (ii) sends one or more messages that populate a second playback queue of the particular second media playback system with audio tracks of the first playback queue.

Abstract: Example techniques may involve tuning a music discovery dial. An implementation may include displaying, on the touch-sensitive circular graphical display, a circular graphical user interface including multiple wedge-shaped selectable regions arranged around the circumference of the circular graphical user interface, each wedge-shaped selectable region corresponding to a respective streaming audio channel. The implementation may include detecting a touch input in a circular motion to the touch-sensitive circular graphical display and causing a paired playback device to play back an audio content snippet corresponding to each selectable regions that the touch input enters. The implementation may further include switching the playback device from playing back a given pre-cached audio content snippet to playing back the full audio track from one or more servers of a streaming audio service.

Abstract: Example techniques involve systems with multiple acoustic echo cancellers. An example implementation captures first audio within an acoustic environment and detecting, within the captured first audio content, a wake-word. In response to the wake-word and before playing an acknowledgement tone, the implementation activates (a) a first sound canceller when one or more speakers are playing back audio content or (b) a second sound canceller when the one or more speakers are idle. In response to the wake-word and after activating either (a) the first sound canceller or (b) the second sound canceller, the implementation outputs the acknowledgement tone via the one or more speakers. The implementation captures second audio within the acoustic environment and cancelling the acoustic echo of the acknowledgement tone from the captured second audio using the activated sound canceller.

Abstract: Content rules engines for playback devices are disclosed herein. A media playback system receives a first command to form a synchrony group comprising a plurality of playback devices. The system receives a second command for the synchrony group to play back first audio content. In response to the second command, the first audio content is played back via the synchrony group. The system receives (i) second audio content to be played back by one or more of the playback devices of the synchrony group and (ii) content source properties associated with an audio source of the second audio content. The system accesses a rules engine to determine playback restrictions based at least in part on the content source properties. Based at least in part on the playback restrictions, operation of one or more of the playback devices is restricted.

Abstract: Systems and methods for limiting volume in an audio playback device using a feedback controller are disclosed herein. In one example, a gain stage modulates gain of an audio signal based in part on feedback from a downstream limiter. The gain stage receives a first audio signal as well as a feedback signal from the feedback controller. Based at least in part on the feedback signal from the feedback controller, the gain stage modulates a gain of the first audio signal to provide a second audio signal. The second audio signal is delivered to the limiter, which limits the second audio signal to produce an output signal. The output signal is played back via a transducer. The feedback controller receives a gain reduction value from the limiter and determines a feedback signal to provide to the gain stage upstream of the limiter.

Abstract: In one aspect, a playback device is configured to (i) receive a first stream of audio data representing audio content from a computing system, (ii) detect an indication that a source of the audio content is to switch from the computing system to a user device; (iii) after detecting the indication, establish a point-to-point wireless link with the user device over which to receive a second stream of audio data; (iv) receive the second stream of audio data representing the audio content; (v) determine a future time at which to transition from playing back the audio content using the first stream of audio data to playing back the audio content using the second stream of audio data; and (vi) at the future time, transition from playing back the audio content using the first stream of audio data to playing back the audio content using the second stream of audio data.

Abstract: System, method, and apparatus including receiving an identification of content played by a playback system and an identification of location of the playback system. A playlist of content is associated with the location. A request is received to retrieve the playlist of content and the requested playlist of content is sent to a playback system.

Abstract: In one aspect, a first playback device is configured to (i) receive a set of voice signals, (ii) process the set of voice signals using a first set of audio processing algorithms, (iii) identify, from the set of voice signals, at least two voice signals that are to be further processed, (iv) determine that the first playback device does not have a threshold amount of computational power available, (v) receive an indication of an available amount of computational power of a second playback device, (vi) send the at least two voice signals to the second playback device, (vii) cause the second playback device to process the at least two voice signals using a second set of audio processing algorithms, (viii) receive, from the second playback device, the processed at least two voice signals, and (ix) combine the processed at least two voice signals into a combined voice signal.

Abstract: Systems and methods for authenticating a passive speaker include (i) activating, by a playback device configured to drive the passive speaker, a passive speaker identification circuit of the passive speaker by providing an identification signal to an input terminal of the passive speaker, wherein the passive speaker is a particular type of passive speaker having particular acoustic characteristics; (ii) while the passive speaker identification circuit is active, measuring, by the playback device, an electrical current of the identification signal; (iii) determining, based on the measured electrical current of the identification signal, an impedance modulation of the passive speaker; (iv) determining, by the playback device, the particular type of the passive speaker based on the impedance modulation of the passive speaker; and (v) applying, by the playback device, a calibration to the playback device based on the determined particular type of the passive speaker.

Abstract: Example techniques relate to prioritizing media content requests. An example implementation involves a computing system receives an explicit request to play back a playlist on one or more playback devices of a media playback system. The computing system causes the playback devices to play back a given audio track of the playlist. While the playback devices are playing back first tracks of the playlist, the computing system receives one or more implicit requests for second audio tracks in the playlist. While the playback devices are playing back the second audio tracks of the playlist, the computing system receives an explicit request to play back audio content on a mobile device. The computing system determines that the request to play back the audio content on the mobile device is a higher priority than the requests for second audio tracks and switches playback from the playback devices to the mobile device.

Abstract: Some disclosed systems and methods include assigning channel streams to satellite playback devices, delaying initial transmission of surround sound content to satellite playback devices to accumulate audio samples for transmission in individual frames of surround sound content, and taking advantage of configured playback delays for different channels of surround sound content to prioritize transmission of channels of surround sound content having shorter configured playback delays over transmission of channels of surround sound content having longer configured playback delays.

Abstract: Example techniques described herein involve a point-of-contact (POC) playback device that operates as an intermediary between the cloud and a media playback system that includes the POC playback device. As the intermediary, when the cloud issues a command to the media playback system, the POC playback device may perform some or all processing of the command to determine how to implement that command in the media playback system. For instance, the POC playback device may determine the target devices for a command, and then cause the target devices to carry out the command. This processing by the POC playback device may simplify control of the media playback system from the perspective of third party controllers, as these controllers need not have full and/or completely up-to-date knowledge of the media playback system functionality and status, among other possible benefits.

Abstract: Example techniques involve a calibration state variable. An example implementation receives, via a network interface, an indication that the first playback device is calibrated. Based on receiving the indication that the first playback device is calibrated, the example implementation updates a calibration state variable to indicate that the first playback device is calibrated, wherein the calibration state variable is stored in the data storage. The example implementation sends, via the network interface, an indication of the updated calibration state variable to a second device.

Abstract: Examples described herein relate to music discovery. In one aspect, a method is provided that involves (a) receiving by a computing device an indication of a search tool from among a plurality of search tools, where each search tool of the plurality of search tools is associated with at least one respective media service, (b) receiving by the computing device an indication of a media characteristic, where the computing device receives the media characteristic via the indicated search tool, (c) selecting by the computing device one or more of the at least one respective media service that maintains media associate with the indicated media characteristic, and (d) sending by the computing device an indication of the selected one or more of the at least one respective media service.

Abstract: Systems and methods for optimizing network microphone devices using noise classification are disclosed herein. In one example, individual microphones of a network microphone device (NMD) detect sound. The sound data is analyzed to detect a trigger event such as a wake word. Metadata associated with the sound data is captured in a lookback buffer of the NMD. After detecting the trigger event, the metadata is analyzed to classify noise in the sound data. Based on the classified noise, at least one performance parameter of the NMD is modified.

Abstract: Systems and methods for suppressing noise and detecting voice input in a multi-channel audio signal captured by two or more network microphone devices include receiving an instruction to process one or more audio signals captured by a first network microphone device and after receiving the instruction (i) disabling at least a first microphone of a plurality of microphones of a second network microphone device, (ii) capturing a first audio signal via a second microphone of the plurality of microphones, (iii) receiving over a network interface of the second network microphone device a second audio signal captured via at least a third microphone of the first network microphone device, (iv) using estimated noise content to suppress first and second noise content in the first and second audio signals, (v) combining the suppressed first and second audio signals into a third audio signal, and (vi) determining that the third audio signal includes a voice input comprising a wake word.