Patent classifications
H04R29/007
Playback Device Calibration Based on Representation Spectral Characteristics
A computing device may maintain a database of representative spectral characteristics. The computing device may also receive particular spectral data associated with a particular playback environment corresponding to the particular playback device. Based on the particular spectral data, the computing device may identify one of the representative spectral characteristics from the database that substantially matches the particular spectral data, and then identify, in the database, an audio processing algorithm based on a) the identified representative spectral characteristic and b) at least one characteristic of the particular playback device. The computing device may then transmit, to the particular playback device, data indicating the identified audio processing algorithm.
METHOD TO DETERMINE LOUDSPEAKER CHANGE OF PLACEMENT
A system and method is described for determining whether a loudspeaker device has relocated, tilted, rotated, or changed environment such that one or more parameters for driving the loudspeaker may be modified and/or a complete reconfiguration of the loudspeaker system may be performed. In one embodiment, the system may include a set of sensors. The sensors provide readings that are analyzed to determine 1) whether the loudspeaker has moved since a previous analysis and/or 2) a distance of movement and/or a degree change in orientation of the loudspeaker since the previous analysis. Upon determining the level of movement is below a threshold value, the system adjusts previous parameters used to drive one or more of the loudspeakers. By adjusting previous parameters instead of performing a complete recalibration, the system provides a more efficient technique for ensuring that the loudspeakers continue to produce accurate sound for the listener.
Default Playback Devices
Systems and method discussed herein involve applying a designation of a default playback device in a media playback system. One method may involve maintaining a database comprising data indicating an assignment of an identification of a network microphone device to a playback zone of a media playback system, receiving a message indicating (i) the identification of the network microphone device and (ii) a media playback command, identifying the playback zone in the media playback system based on the data in the database and the received message, and transmitting to the playback zone, a message indicating the media playback command.
Audio Response Playback
A voice command may be received from a microphone device associated with a media playback system comprising one or more zones. An audio response zone from the one or more zones to play the audio response may be selected based on context information. The selected zone may comprise one or more playback devices. At least one playback device of the one or more playback devices of the selected zone may be caused to play the audio response.
SYSTEM AND METHOD FOR WIRELESS MICROPHONE TRANSMITTER TRACKING USING A PLURALITY OF ANTENNAS
In at least one embodiment, a system for monitoring movement of a wireless microphone that transmits an audio signal on a stage is provided. The system includes a plurality of antennas for being positioned on stage and each being positioned on a different zone of the stage and each being configured to wirelessly receive an audio signal from a wireless microphone. The system further includes a controller that is operably coupled to each antenna. The controller is configured to determine the signal strength for the audio signal received at each antenna at least two or more times and to determine a signal strength trend for each antenna in response to determining the signal strength for the audio signal at each antenna at least two or more times.
Compensation for Speaker Nonlinearities
A first signal may be received indicative of audio to be played by a speaker. A second signal may be received which comprises (i) a voice input received by a microphone and (ii) at least a portion of the audio played by the speaker at a same time that the microphone receives the voice input. Based on the first signal, nonlinearities output by the speaker which played the audio may be determined. At least the nonlinearities from the second signal may be removed to output a third signal comprising substantially the voice input received at the microphone.
Background noise measurement from a repeated stimulus measurement system
A minimum level for a stimulation signal used in room correction processing is determined by measuring background noise. The stimulation signal is repeated a number of times and resulting responses are recorded. The recording responses are averaged, and the average is subtracted from each recorded response to obtain the background noise present in each recorded response. A stimulation signal to background noise ratio is computed from the stimulation signal and background noise and compared to an SNR threshold to determine if the stimulation signal level is sufficient to support the room correction processing. The background noise may be AC hum introduced electronically into the response signal, acoustic noise introduced by AC ventilation systems or noise emitting devices (refrigerators, etc), and it may be structure-born noise introduced by shaking the microphone, e.g. a bus drives by, shaking the floor the microphone is standing on.
Calibration using multiple recording devices
Example techniques may involve calibration with multiple recording devices. An implementation may include detecting, via a microphone, one or more calibration sounds as emitted by one or more playback devices of one or more zones during a calibration sequence. The implementation may further include determining a first response, the first response representing a response of a given environment to the one or more calibration sounds as detected by the first recording device and receiving data indicating a second response, the second response representing a response of the given environment to the one or more calibration sounds as detected by a second recording device. The implementation may also include determining a calibration for the one or more playback devices based on the first response and the second response and sending, to the one or more zones, an instruction that applies the calibration to playback by the one or more playback devices.
Multi-orientation playback device microphones
Aspects of a multi-orientation playback device including at least one microphone array are discussed. A method may include determining an orientation of the playback device which includes at least one microphone array and determining at least one microphone training response for the playback device from a plurality of microphone training responses based on the orientation of the playback device. The at least one microphone array can detect a sound input, and the location information of a source of the sound input can be determined based on the at least one microphone training response and the detected sound input. Based on the location information of the source, the directional focus of the at least one microphone array can be adjusted, and the sound input can be captured based on the adjusted directional focus.
Calibration using multiple recording devices
Example techniques may involve calibration with multiple recording devices. An implementation may include a mobile device receiving data indicating that a calibration sequence for multiple playback devices has been initiated in a venue. The mobile device displays a prompt to include the first mobile device in the calibration sequence for the multiple playback devices and a particular selectable control that, when selected, includes the first mobile device in the calibration sequence. During the calibration sequence, the mobile device records calibration audio as played back by the multiple playback devices and transmits data representing the recorded calibration audio to a computing device. The computing device determines a calibration for the multiple playback devices in the venue based on the data representing the calibration audio recorded by the first mobile device and data representing calibration audio recorded by second mobile devices while the multiple playback devices played back the calibration audio.