Calibration of a playback device based on an estimated frequency response

Patent metadata

Field	Value
Publication number	US-10853027-B2
Application number	US-201916665415-A
Country	US
Kind code	B2
Filing date	Oct 28, 2019
Priority date	Aug 5, 2016
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

An example playback device is configured to receive a first stream of audio comprising source audio content to be played back by the playback device and record, via one or more microphones of the playback device, an audio signal output by the playback device based on the playback device playing the source audio content. The playback device is also configured to determine a transfer function between a frequency-domain representation of the first stream of audio and a frequency-domain representation of the recorded audio signal, and then determine an estimated frequency response of the playback device based on a difference between (i) the transfer function and (ii) a self-response of the playback device, where the self-response of the playback device is stored in a memory of the playback device. Based on the estimated frequency response, the playback device is configured to determine an acoustic calibration adjustment and implement the acoustic calibration adjustment.

First claim

We claim:

1. A playback device comprising:
at least one processor;
non-transitory computer-readable medium; and
program instructions stored on the non-transitory computer-readable medium that are executable by the at least one processor and thereby cause the playback device to be configured to:
receive a first stream of audio comprising source audio content to be played back by the playback device in a given playback environment;
record, via one or more microphones of the playback device, an audio signal output by the playback device based on the playback device playing the source audio content in the given playback environment;
determine a transfer function between a frequency-domain representation of the first stream of audio and a frequency-domain representation of the recorded audio signal;
determine an estimated frequency response of the playback device in the given playback environment based on a difference between (i) the transfer function and (ii) a self-response of the playback device, wherein the self-response of the playback device comprises a predetermined value stored in a memory of the playback device; and
based on the estimated frequency response of the playback device in the given playback environment, determine an acoustic calibration adjustment for the playback device; and
implement the acoustic calibration adjustment.

2. The playback device of claim 1 , further comprising program instructions stored on the non-transitory computer-readable medium that are executable by the at least one processor and thereby cause the playback device to be configured to:
determine that a volume setting of the playback device during playback of the source audio content is within a threshold volume range, wherein determining the estimated frequency response of the playback device in the given playback environment is based on determining that the volume setting of the playback device during playback of the source audio content is within a threshold volume range.

3. The playback device of claim 1 , further comprising program instructions stored on the non-transitory computer-readable medium that are executable by the at least one processor and thereby cause the playback device to be configured to:
transmit, to a computing device, at least the recorded audio signal; and
receive, from the computing device, the transfer function.

4. The playback device of claim 1 , wherein the program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to receive the first stream of audio comprise program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to receive music content from a cloud-based music service provider.

5. The playback device of claim 1 , further comprising program instructions stored on the non-transitory computer-readable medium that are executable by the at least one processor and thereby cause the playback device to be configured to:
determine that the audio playback device has changed at least one of spatial location or orientation, wherein determining the estimated frequency response comprises calculating the estimated frequency response in response to determining that the audio playback device has changed at least one of spatial location or orientation.

6. The playback device of claim 5 , wherein the playback device further comprises at least one motion sensor, and wherein the program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to determine that the audio playback device has changed at least one of spatial location or orientation comprise program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to detect, via the at least one motion sensor, that the audio playback device has changed at least one of spatial location or orientation.

7. The playback device of claim 1 , further comprising program instructions stored on the non-transitory computer-readable medium that are executable by the at least one processor and thereby cause the playback device to be configured to:
determine a spectral coverage of the source audio content prior to calculating the estimated frequency response.

8. The playback device of claim 1 , wherein the program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to implement the acoustic calibration adjustment comprise program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to implement the acoustic calibration adjustment during playback of the source audio content by the playback device in the given playback environment.

9. The playback device of claim 1 , wherein the program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to determine an acoustic calibration adjustment for the playback device comprise program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to select an audio processing algorithm from a database of audio processing algorithms stored in the memory of the playback device.

10. The playback device of claim 1 , wherein the program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to determine an acoustic calibration adjustment for the playback device comprise program instructions that are executable by the at least one processor and thereby cause the playback device to be configured to calculate an audio processing algorithm based on the estimated frequency response.

11. The playback device of claim 1 , further comprising program instructions stored on the non-transitory computer-readable medium that are executable by the at least one processor and thereby cause the playback device to be configured to:
determine that the playback device has been configured in a bonded zone with a second playback device for synchronous playback of separate channels of the source audio content, wherein determining the estimated frequency response comprises determining the estimated frequency response in response to determining that the playback device has been configured in a bonded zone with the second playback device.

12. The playback device of claim 1 , wherein the estimated frequency response is an estimated sound pressure level output of the audio playback device as a function of input frequency.

13. The playback device of claim 1 , wherein the self-response of the audio playback device is determined during a testing phase in an anechoic chamber of another audio playback device that is similar to the audio playback device.

14. A non-transitory computer-readable medium, wherein the non-transitory computer-readable medium is provisioned with program instructions that are executable by at least one processor such that a playback device is configured to:
receive a first stream of audio comprising source audio content to be played back by the playback device in a given playback environment;
record, via one or more microphones of the playback device, an audio signal output by the playback device based on the playback device playing the source audio content in the given playback environment;
determine a transfer function between a frequency-domain representation of the first stream of audio and a frequency-domain representation of the recorded audio signal;
determine an estimated frequency response of t

Assignees

• Sonos Inc

Inventors

• Shih Shao-Fu
• Mcpherson Patrick

Classifications

• H04R29/007 Primary

  for public address systems (public address systems per se H04R27/00) · CPC title

• H04R2227/003

  Digital PA systems using, e.g. LAN or internet · CPC title

• H04R3/04

  for correcting frequency response · CPC title

• H04R2420/07

  Applications of wireless loudspeakers or wireless microphones · CPC title

• H04R2227/007

  Electronic adaptation of audio signals to reverberation of the listening space for PA · CPC title