Systems and methods for calibrating speakers
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 using a portable electronic device comprising:
establishing, by the portable electronic device, a network connection between the portable electronic device and the network-connected speaker system;
rendering, via a user interface of the portable electronic device, instructions for repositioning the portable electronic device within an environment of the network-connected speaker system;
sending from the portable electronic device to the network-connected-speaker system, via the network connection, a signal initiating playback of a piece of audio content by the network-connected speaker system from an Internet music library;
detecting playback of at least a first portion of the piece of audio content by a microphone of the portable electronic device at a first location within the environment;
detecting playback of at least a second portion of the piece of audio content by the microphone of the portable electronic device at a second location within the environment;
determining, based at least in part on the detected playback of the at least a first portion of the piece of audio content and the detected playback of the at least a second portion of the piece of audio content, one or more adjustments to be applied to additional audio content before additional audio content playback by the network-connected speaker system, wherein determining the one or more adjustments comprises:
accessing a system information file of the portable electronic device to determine a transfer function of the microphone, and
determining the one or more adjustments using, at least in part, the transfer function of the microphone; 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 piece of audio content comprises one or more patterns.
3. The method of claim 2 , wherein the one or more patterns comprise one or more synchronization patterns.
4. The method of claim 3 , wherein determining the one or more adjustments to be applied to the additional audio content further comprises aligning the detected playback of the at least a first portion of the piece of audio content with the detected playback of the at least a second portion of the piece of audio content based, at least in part, on the one or more synchronization patterns.
5. A method for calibrating a network-connected speaker system using a portable electronic device comprising:
establishing, by the portable electronic device, a network connection between the portable electronic device and the network-connected speaker system;
rendering, via a user interface of the portable electronic device, instructions for repositioning the portable electronic device within an environment of the network-connected speaker system;
sending from the portable electronic device to the network-connected-speaker system, via the network connection, a signal initiating playback of a piece of audio content by the network-connected speaker system;
detecting playback of at least a first portion of the piece of audio content by a microphone of the portable electronic device at a first location within the environment;
detecting playback of at least a second portion of the piece of audio content by the microphone of the portable electronic device at a second location within the environment;
determining, based at least in part on the detected playback of the at least a first portion of the piece of audio content and the detected playback of the at least a second portion of the piece of audio content, one or more adjustments to be applied to additional audio content before additional audio content playback by the network-connected speaker system, wherein determining the one or more adjustments comprises:
accessing a system information file of the portable electronic device to determine a transfer function of the microphone,
communicating a request to a connected service separate from the portable electronic device, the request comprising one or more of the detected playback of the at least a first portion of the piece of audio content and the detected playback of the at least a second portion of the piece of audio content, the request further comprising information relating to the transfer function of the microphone, and
receiving a response from the connected service comprising the one or more adjustments, and
applying the one or more adjustments to the additional audio content before it is played by the network-connected speaker system.
6. The method of claim 1 , wherein the portable electronic device comprises a smartphone.
7. The method of claim 1 , wherein the portable electronic device comprises a tablet.
8. The method of claim 1 , wherein determining the one or more adjustments to be applied to the additional audio content further comprises performing spectral analysis on the detected playback of the at least a first portion of the piece of audio content and the detected playback of the at least a second portion of the piece of audio content.
9. The method of claim 1 , wherein determining the one or more adjustments to be applied to the additional audio content further comprises comparing frequency responses of the detected playback of the at least a first portion of the piece of audio content and the detected playback of the at least a second portion of the piece of audio content with an ideal frequency response.
10. The method of claim 1 , wherein determining the transfer function of the microphone comprises accessing locally stored transfer function information associated with the system information file.
11. The method of claim 1 , wherein the at least a first portion of the piece of audio content and the at least a second portion of the piece of audio content comprise different portions of the piece of audio content.
12. The method of claim 1 , wherein the at least a first portion of the piece of audio content and the at least a second portion of the piece of audio content comprise the same portion of the piece of audio content.
13. The method of claim 1 , wherein the at least a first portion of the piece of audio content and the at least a second portion of the piece of audio content comprise portions of audio content that overlap at least in part.
14. A method for calibrating a network-connected speaker system using a portable electronic device comprising:
establishing, by the portable electronic device, a network connection between the portable electronic device and the network-connected speaker system;
rendering, via a user interface of the portable electronic device, instructions for repositioning the portable electronic device within an environment of the network-connected speaker system;
sending from the portable electronic device to the network-connected-speaker system, via the network connection, a signal initiating playback of a piece of audio content by the network-connected speaker system;
detecting playback of at least a first portion of the piece of audio content by a microphone of the portable electronic device at a first location within the environment;
detecting playback of at least a second portion of the piece of audio content by the microphone of the portable electronic device at a second location within the environment;
determining, based at least in part on the detected playback of the at least a first portion of the piece of audio content and the detected playback of the at least a second portion of the piece of audio content, one or more adjustments to be applied to additional audio content before additional audio content playback by the network-connected speaker system, wherein determining the one or more adjustments comprises:
accessing a system information file of the portable electronic device to determine a transfer function of the microphone, wherein determining the transfer function of the microphone comprises:
retrieving a mobile device identifier from the system information file, and
retrieving the transfer function of the microphone from a set of microphone transfer functions using a web service based on the mobile device identifier, and
determining the one or more adjustments using, at least in part, the transfer function of the microphone; and
applying the one or more adjustments to the additional audio content before it is played by the network-connected speaker system.
15. The method of claim 5 , wherein the signal communicated from the portable electronic device comprises an electronic file corresponding to the piece of audio content.