Concurrent multi-loudspeaker calibration with a single measurement

Patent metadata

Field	Value
Publication number	US-9648422-B2
Application number	US-201514805340-A
Country	US
Kind code	B2
Filing date	Jul 21, 2015
Priority date	Jun 28, 2012
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

An example implementation may involve a control device detecting a trigger condition that initiates calibration of a plurality of playback devices. The control device may send, to the playback devices of the plurality, respective commands that instruct the playback devices to repeatedly emit the calibration sound according to a sequence. The commands may instruct the one or more playback devices to stagger emission of the calibration sounds such that each emitted calibration sound is delayed relative to a preceding calibration sound in the sequence. The control device may detect the emitted calibration sounds via a microphone.

First claim

We claim:

1. A non-transitory computer-readable medium having stored therein instructions executable by one or more processors to cause a device to perform operations comprising:
detecting a trigger condition that initiates calibration of a plurality of playback devices, wherein calibrating the plurality of playback devices comprises a given number of playback devices respectively emitting a calibration sound according to a sequence;
sending, to a first playback device of the plurality of playback devices, a command that instructs the first playback device to repeatedly emit the calibration sound according to the sequence, wherein the calibration sound cycles through frequencies of a calibration frequency range, and wherein a duration of the calibration sound is proportional to the given number of playback devices in the plurality of playback devices;
sending, to one or more additional playback devices of the plurality of playback devices, respective commands that instruct the one or more additional playback devices to repeatedly emit the respective calibration sound according to the sequence, wherein the commands instruct the one or more additional playback devices to stagger emission of the calibration sounds such that each emitted calibration sound is delayed relative to a preceding calibration sound in the sequence; and
detecting, via a microphone, the emitted calibration sounds.

2. The non-transitory computer-readable medium of claim 1 , wherein repeatedly emitting the calibration sound that cycles through frequencies of the calibration frequency range comprises outputting a hybrid sound that comprises (i) a first component that includes noise at frequencies between a minimum of the calibration frequency range and a first threshold frequency, and (ii) a second component that sweeps through frequencies between a second threshold frequency and a maximum of the calibration frequency range.

3. The non-transitory computer-readable medium of claim 2 , wherein the second threshold frequency is a lower frequency than the first threshold frequency such that the first component and the second component overlap in a transition frequency range that includes frequencies between the second threshold frequency and the first threshold frequency.

4. The non-transitory computer-readable medium of claim 1 , wherein repeatedly emitting the calibration sound that cycles through frequencies of the calibration frequency range comprises outputting (i) a first sound that includes noise at frequencies between a minimum of the calibration frequency range and a first threshold frequency, and (ii) a second sound that sweeps through frequencies between a second threshold frequency and a maximum of the calibration frequency range.

5. The non-transitory computer-readable medium of claim 1 , wherein the calibration sound comprises a baseline tone that covers frequencies of the calibration frequency range within a given duration, and wherein the operations further comprise:
selecting, as the calibration sound, a particular calibration sound that is substantially proportional in duration to the product of the given duration of the baseline tone and the given number of playback devices of the plurality of playback devices.

6. The non-transitory computer-readable medium of claim 1 , wherein the calibration sound comprises a baseline tone that covers frequencies of the calibration frequency range within a given duration, and wherein the operations further comprise:
selecting, as the calibration sound, a particular calibration sound that is substantially proportional in duration to the product of the given duration of the baseline tone and the given number of playback devices of the plurality of playback devices rounded up to the nearest power of two.

7. The non-transitory computer-readable medium of claim 1 , wherein the calibration sound comprises a baseline tone that covers frequencies of the calibration frequency range within a given duration, and wherein the operations further comprise:
generating the calibration sound by increasing the given duration of the baseline tone to a duration that is proportional to the product of the given duration of the baseline tone and the given number of playback devices of the plurality of playback devices rounded up to the nearest power of two.

8. The non-transitory computer-readable medium of claim 7 , wherein the operations further comprise generating the baseline tone by combining (i) a first component that includes noise at frequencies between a minimum of the calibration frequency range and a first threshold frequency, and (ii) a second component that sweeps through frequencies between a second threshold frequency and a maximum of the calibration frequency range.

9. The non-transitory computer-readable medium of claim 1 , wherein the calibration sound comprises a baseline tone that covers frequencies of the calibration frequency range within a given duration, and wherein instructing the one or more additional playback devices to stagger emission of the calibration sounds comprises instructing each of the one or more playback devices to delay emission of the calibration tone by a portion of the given duration of the baseline tone.

10. The non-transitory computer-readable medium of claim 9 , wherein instructing each of the one or more playback devices to delay emission of the calibration tone comprises instructing each of the one or more playback devices to delay emission of the calibration tone by approximately one half of the duration of the calibration tone.

11. The non-transitory computer-readable medium of claim 1 , wherein detecting, via the microphone, the emitted calibration sounds comprises detecting the emitted calibration sounds in the sequence, and wherein the operations further comprise:
identifying, among the detected calibration sounds, the calibration sounds emitted by each playback device based on the sequence in which the plurality of playback device emitted the calibration sounds.

12. The non-transitory computer-readable medium of claim 1 , wherein each calibration sound comprises a notch at a respective frequency, and wherein the operations further comprise:
identifying, among the detected calibration sounds, the calibration sounds emitted by each playback device based on the respective notches in the detected calibration sounds.

13. The non-transitory computer-readable medium of claim 12 , wherein the operations further comprise:
determining, from the identified calibration sounds, a respective frequency response of each playback device; and
calibrating each playback device to equalize the determined frequency response to a calibration frequency response.

14. The non-transitory computer-readable medium of claim 1 , wherein the operations further comprise:
sending the calibration sound to the first playback device and to the one or more additional playback devices.

15. The non-transitory computer-readable medium of claim 1 , wherein the calibration range is inclusive of frequencies from 20-20,000 Hertz.

16. The non-transitory computer-readable medium of claim 1 , wherein detecting the trigger condition that initiates concurrent calibration of a plurality of playback devices comprises detecting input data indicating selection of a selectable control that when selected, causes calibration of the plurality of playback devices.

17. The non-transitory computer-readable medium of claim 1 , wherein detecting the trigger condition that initiates concurrent calibration of a plurality of playback devices comprises detecting that a physical movement of one

Assignees

• Sonos Inc

Inventors

• Sheen Timothy
• Ramos Aurelio

Classifications

• H04R27/00

  Public address systems (circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; {monitoring or testing arrangements for public address systems H04R29/007}; amplifiers H03F) · CPC title

• H04R3/12

  for distributing signals to two or more loudspeakers {(specially adapted for hearing aids H04R25/407)} · CPC title

• H03G3/20

  Automatic control ({H03G3/005 takes precedence;} combined with volume compression or expansion H03G7/00) · CPC title

• H04R2227/005

  Audio distribution systems for home, i.e. multi-room use · CPC title

• H03G5/165 Primary

  Equalizers; Volume or gain control in limited frequency bands · CPC title