AUDIO REPRODUCTION SYSTEMS AND METHODS
Systems and method are disclosed for facilitating efficient calibration of filters for correcting room and/or speaker-based distortion and/or binaural imbalances in audio reproduction, and/or for producing three-dimensional sound in stereo system environments. According to some embodiments, using a portable device such as a smartphone or tablet, a user can calibrate speakers by initiating playback of a test signal, detecting playback of the test signal with the portable device's microphone, and repeating this process for a number of speakers and/or device positions (e.g., next to each of the user's ears). A comparison can be made between the test signal and the detected signal, and this can be used to more precisely calibrate rendering of future signals by the speakers.
1 . A method for calibrating a network-connected speaker system, the method comprising:
identifying a change in an environment of the network-connected speaker system;
detecting, in response to identifying the change in the environment of the network-connected speaker system, playback of at least a portion of a piece of audio content by a microphone of the network-connected speaker system;
identifying, based at least in part on the detected playback of the at least a portion of the piece of audio content, at least one characteristic of the environment of the network-connected speaker system, wherein identifying the at least one characteristic is based, at least in part, on a transfer function of the microphone of the network-connected speaker system;
determining, based at least in part on the identified at least one characteristic of the environment of the network-connected speaker system, one or more adjustments to be applied to additional audio content before additional audio content playback from the one or more speakers by the network-connected speaker system; and
applying the one or more adjustments to the additional audio content before it is played by the network-connected speaker system.
2 . The method of claim 1 , wherein the method further comprises initiating playback of the piece of audio content by one or more speakers of the network-connected speaker system from an Internet music library;
3 . The method of claim 2 , wherein the method further comprises establishing a connection between the network-connected speaker system and a mobile device.
4 . The method of claim 3 , wherein initiating playback of the piece of audio content is performed in response to a signal received from the mobile device.
5 . The method of claim 1 , wherein identifying the at least one characteristic of the environment of the network-connected speaker system and determining the one or more adjustments to be applied to additional audio content before additional audio content playback are performed, at least in part, using a service in communication with the network-connected speaker system.
6 . The method of claim 1 , wherein identifying the at least one characteristic of the environment of the network-connected speaker system comprises:
comparing a frequency response of the detected playback of the at least a portion of the piece of audio content with a reference frequency response; and
identifying the at least one characteristic of the environment of the network-connected speaker system based, at least in part, on the comparison.
7 . The method of claim 6 , wherein the reference frequency response is associated with the at least a portion of the piece of audio content.
8 . The method of claim 6 , wherein comparing the frequency response of the detected playback of the at least a portion of the piece of audio content with the reference frequency response comprises aligning the frequency response of the detected playback of the at least a portion of the piece of audio content with the reference frequency response.
9 . The method of claim 8 , wherein the piece of audio content comprises one or more patterns.
10 . The method of claim 9 , wherein the one or more patterns comprise synchronization patterns.
11 . The method of claim 9 , wherein aligning the frequency response of the detected playback of the at least a portion of the piece of audio content with the reference frequency response is based, at least in part, on the one or more patterns.
12 . The method of claim 1 , wherein the method further comprises accessing the transfer function of the microphone from local storage of the network-connected speaker system.
13 . The method of claim 1 , wherein the method further comprises accessing the transfer function of the microphone from a remote library.
14 . The method of claim 1 , wherein identifying the at least one characteristic of the environment of the network-connected speaker system comprises comparing the detected playback of the at least a portion of the piece of audio content with one or more reference frequency responses associated with one or more reference environments.
15 . The method of claim 1 , wherein identifying the at least one characteristic of the environment of the network-connected speaker system comprises identifying that the environment of the network-connected speaker system is an outdoor environment.
16 . The method of claim 1 , wherein identifying the at least one characteristic of the environment of the network-connected speaker system comprises identifying that the environment of the network-connected speaker system is an indoor environment.
17 . The method of claim 16 , wherein the at least one characteristic of the environment of the network-connected speaker system is a characteristic of a room environment.
18 . The method of claim 1 , wherein identifying the at least one characteristic of the environment of the network-connected speaker system further comprises performing spectral analysis on the detected playback of the at least a portion of the piece of audio content.