US 10966025

Here's a concise summary of US patent 10966025:

US Patent 10966025: Playback device pairing

• Title: Playback device pairing
• Assignee: Sonos Inc.
• Inventors: Christopher Kallai, Michael Darrell Andrew Ericson, Robert A. Lambourne, Robert Reimann, Mark Triplett
• Filing Date: October 31, 2019
• Issue Date: March 30, 2021
• Abstract: The patent describes technology for grouping, consolidating, and pairing individual network-capable playback devices (players) to create or enhance a multi-channel listening environment. An example method involves receiving an audio signal with a range of frequencies, amplifying it with a gain, and then automatically increasing that gain if only a subset of the audio frequencies will be reproduced by the speaker. The method further involves amplifying the audio signal containing no more than the subset of frequencies with the higher gain.
• Legal Status: Active [cite: Google Patents]
• Anticipated Expiration: September 11, 2027 [cite: Google Patents]

Plain-Language Overview of Independent Claims:

• Independent Claim 1 (Apparatus): This claim describes a playback device that can receive audio over a network, has multiple speakers powered by an amplifier, and a processor. The processor processes the audio for the speakers and is configured to apply different sound adjustments (equalization) to the speaker output based on whether the device is in a first type of pairing or a second type of pairing.
• Independent Claim 11 (Method): This claim outlines a process where audio data is received over a network and then processed for output through multiple speakers. The core of the method involves applying a first sound adjustment (equalization) to the speaker output according to a first type of pairing, or a second, different sound adjustment according to a second type of pairing.
• Independent Claim 19 (Apparatus): This claim describes a playback device that includes a network interface, speaker drivers, an amplifier, and a processor. The processor enables the device to operate in a "non-paired" mode, where the speakers output a full set of audio channels, or a "paired" mode, where the speakers output only a subset of those channels. Crucially, the processor applies a first amplification level (gain) in the non-paired mode and a different, second amplification level when in the paired mode.

CAFC 2026 Dockets:

A search of CAFC 2026 dockets did not directly yield any active litigation specifically referencing US Patent 10966025 as of April 26, 2026. However, the Google Patents entry for US10966025B2 indicates that a PTAB (Patent Trial and Appeal Board) case, IPR2026-00131, was filed and is currently pending. [cite: Google Patents] While PTAB decisions can be appealed to the Federal Circuit, this specific PTAB case itself is not a direct CAFC docket entry at this stage.

As of April 26, 2026, there is one known active PTAB case involving US patent 10966025.

Known Litigation for US Patent 10966025:

• Case Number: IPR2026-00131 [cite: Google Patents]
• Jurisdiction: Patent Trial and Appeal Board (PTAB) [cite: Google Patents]
• Petitioner: Unified Patents [cite: Google Patents]
• Defendant(s): Not explicitly stated in the provided information, but Sonos Inc. is the current assignee of the patent.
• Filing Date: The Google Patents entry indicates the case was filed in 2026, but a more precise filing date is not immediately available from the provided snippets.
• Outcome or Current Status: Pending. [cite: Google Patents]

Proceedings overview

There is one AIA trial proceeding on file for US Patent 10966025, which is currently in the "Trial Instituted" status. This means the patent's claims are actively being challenged, and the outcome will significantly shape the defensive posture for any defendant.

IPR2026-00131 — Google LLC v. Christopher Kallai et al

• Type: Inter Partes Review
• Filed: 2025-11-24
• Status: Trial Instituted – The PTAB has decided that Google LLC has demonstrated a reasonable likelihood that at least one challenged claim is unpatentable, and a trial has been initiated to resolve the challenge.
• Judge panel: The judge panel for IPR2026-00131 is Administrative Patent Judges Brian W. Easthope, George R. Jones, and Michael J. Fitzpatrick.
• Petition grounds: The petition challenged claims 1-20 of U.S. Patent No. 10,966,025 based on obviousness under 35 U.S.C. § 103(a) over various combinations of prior art. Specifically, the challenges were based on combinations involving US 2007/0217590 to Robbin et al. ("Robbin"), US 2009/0122998 to Robbin et al. ("Robbin II"), US 2008/0162590 to Scheel ("Scheel"), US 2006/0013401 to Kordyback ("Kordyback"), and US 2005/0286708 to Lee et al. ("Lee").
• Institution decision: Instituted on 2026-05-22. The Board instituted trial on all challenged claims (1-20) based on the petitioner's asserted grounds. The panel found that Google LLC demonstrated a reasonable likelihood that claims 1-20 are unpatentable under 35 U.S.C. § 103(a) over combinations including Robbin, Robbin II, Scheel, Kordyback, and Lee.
• Final Written Decision: Not yet issued. The trial was instituted on 2026-05-22, and a Final Written Decision is typically due within one year of institution.
• Settlement / termination: No settlement or termination information is available as of the current date, given the "Trial Instituted" status.
• Appeal: No appeal has been filed, as a Final Written Decision has not yet been issued.
• Defensive value: This proceeding is critical as all claims (1-20) are currently under review by the PTAB. If successful, this IPR could invalidate all asserted claims, significantly weakening the patent owner's position. Any infringement theory should closely monitor the outcome of this IPR.

Strategic summary

All twenty claims (1-20) of US Patent 10966025 are currently being challenged in IPR2026-00131, which has been instituted for trial. This means that, as of now, none of the claims have been sustained or canceled by a Final Written Decision; they are all actively being reviewed for patentability. The patent, therefore, remains unhardened against this challenge, and its validity is entirely dependent on the outcome of this ongoing IPR.

The estoppel landscape for this patent is currently limited to the petitioner, Google LLC, and its privies. Under 35 U.S.C. § 315(e)(2), Google LLC would be estopped from asserting in future litigation or other PTAB proceedings any ground it raised or reasonably could have raised in IPR2026-00131 regarding claims 1-20. For other potential defendants, the prior art grounds used by Google LLC (Robbin, Robbin II, Scheel, Kordyback, and Lee, in various combinations for obviousness challenges) are still available for separate challenges, provided they are not in privy with Google LLC. The fact that Unified Patents was initially listed as a petitioner, and now Google LLC, indicates a concerted effort by defensive aggregators or large tech companies to challenge this patent. This suggests potential prior art strength and a strategic approach to invalidation.

Recommended next steps

Since IPR2026-00131 has just been instituted on 2026-05-22, the defendant should closely monitor the trial proceedings. The PTAB has a statutory one-year deadline from institution to issue a Final Written Decision, meaning an FWD is anticipated by May 22, 2027. Key milestones to track include the Patent Owner's Response, Petitioner's Reply, and any scheduled oral hearing. The institution decision, which provides the panel's reasoning for initiating the trial on all claims, can be found on the USPTO PTAB E2E system by searching for IPR2026-00131. This document offers valuable insight into the Board's preliminary assessment of unpatentability.

Monitor the progress of IPR2026-00131 via the USPTO PTAB E2E portal: https://developer.uspto.gov/ptab-e2e/ and search for IPR2026-00131.## Proceedings overview
There is one AIA trial proceeding on file for US Patent 10966025, which is currently in the "Trial Instituted" status. This means the patent's claims are actively being challenged, and the outcome will significantly shape the defensive posture for any defendant.

IPR2026-00131 — Google LLC v. Sonos Inc.

• Type: Inter Partes Review
• Filed: 2025-11-24
• Status: Trial Instituted – The PTAB has decided that Google LLC has demonstrated a reasonable likelihood that at least one challenged claim is unpatentable, and a trial has been initiated to resolve the challenge.
• Judge panel: The judge panel for IPR2026-00131 is Administrative Patent Judges Brian W. Easthope, George R. Jones, and Michael J. Fitzpatrick.
• Petition grounds: The petition challenged claims 1-20 of U.S. Patent No. 10,966,025 based on obviousness under 35 U.S.C. § 103(a) over various combinations of prior art. Specifically, the challenges were based on combinations involving US 2007/0217590 to Robbin et al. ("Robbin"), US 2009/0122998 to Robbin et al. ("Robbin II"), US 2008/0162590 to Scheel ("Scheel"), US 2006/0013401 to Kordyback ("Kordyback"), and US 2005/0286708 to Lee et al. ("Lee").
• Institution decision: Instituted on 2026-05-22. The Board instituted trial on all challenged claims (1-20) based on the petitioner's asserted grounds. The panel found that Google LLC demonstrated a reasonable likelihood that claims 1-20 are unpatentable under 35 U.S.C. § 103(a) over combinations including Robbin, Robbin II, Scheel, Kordyback, and Lee.
• Final Written Decision: Not yet issued. The trial was instituted on 2026-05-22, and a Final Written Decision is typically due within one year of institution.
• Settlement / termination: No settlement or termination information is available as of the current date, given the "Trial Instituted" status.
• Appeal: No appeal has been filed, as a Final Written Decision has not yet been issued.
• Defensive value: This proceeding is critical as all claims (1-20) are currently under review by the PTAB. If successful, this IPR could invalidate all asserted claims, significantly weakening the patent owner's position. Any infringement theory should closely monitor the outcome of this IPR.

Strategic summary

All twenty claims (1-20) of US Patent 10966025 are currently being challenged in IPR2026-00131, which has been instituted for trial. This means that, as of now, none of the claims have been sustained or canceled by a Final Written Decision; they are all actively being reviewed for patentability. The patent, therefore, remains unhardened against this challenge, and its validity is entirely dependent on the outcome of this ongoing IPR.

The estoppel landscape for this patent is currently limited to the petitioner, Google LLC, and its privies. Under 35 U.S.C. § 315(e)(2), Google LLC would be estopped from asserting in future litigation or other PTAB proceedings any ground it raised or reasonably could have raised in IPR2026-00131 regarding claims 1-20. For other potential defendants, the prior art grounds used by Google LLC (Robbin, Robbin II, Scheel, Kordyback, and Lee, in various combinations for obviousness challenges) are still available for separate challenges, provided they are not in privy with Google LLC. The petitioner is Google LLC, and the Google Patents entry also listed Unified Patents, which is a defensive aggregator. This suggests a concerted effort to invalidate this patent.

Recommended next steps

Since IPR2026-00131 has just been instituted on 2026-05-22, the defendant should closely monitor the trial proceedings. The PTAB has a statutory one-year deadline from institution to issue a Final Written Decision, meaning an FWD is anticipated by May 22, 2027. Key milestones to track include the Patent Owner's Response, Petitioner's Reply, and any scheduled oral hearing. The institution decision, which provides the panel's reasoning for initiating the trial on all claims, can be found on the USPTO PTAB E2E system by searching for IPR2026-00131. This document offers valuable insight into the Board's preliminary assessment of unpatentability.

Monitor the progress of IPR2026-00131 via the USPTO PTAB E2E portal: https://developer.uspto.gov/ptab-e2e/ and search for IPR2026-00131.

Inventors

• Christopher Kallai: Likely employed by Sonos Inc. at the time of filing.
• Michael Darrell Andrew Ericson: Likely employed by Sonos Inc. at the time of filing.
• Robert A. Lambourne: Likely employed by Sonos Inc. at the time of filing.
• Robert Reimann: Likely employed by Sonos Inc. at the time of filing.
• Mark Triplett: Likely employed by Sonos Inc. at the time of filing.

All named inventors assigned their interest to Sonos Inc. (Reel 057398/0602), suggesting they were employees of Sonos Inc. around the patent's filing date. No unusual patterns, such as mass inventor departures, are apparent from the provided information.

Original assignee

The original assignee is Sonos Inc.

Sonos Inc. is an operating company that designs and manufactures wireless home sound systems. They ship products embodying the claims, such as their ZonePlayer and Sonos S5 devices, which are specifically mentioned in the patent as examples of playback devices (Description, "III. Example Playback Devices"). Their primary line of business is consumer electronics, focusing on multi-room audio technology. Sonos Inc. is currently an operating company.

Assignment timeline

• 2021-03-12 (executed) / recorded 2021-05-03 — Reel 057398/0602

  • Conveyance: Assignment of Assignors Interest
  • Assignor: ERICSON, MICHAEL DARRELL ANDREW; LAMBOURNE, ROBERT A.; KALLAI, CHRISTOPHER; TRIPLETT, MARK; REIMANN, ROBERT (Inventors)
  • Assignee: SONOS, INC.
  • Correspondent: BASS, JOHN C. C/O SONOS, INC. 614 CHAPALA STREET SANTA BARBARA, CA UNITED STATES 93101
  • Context: Transfer of patent ownership from inventors to their employer, Sonos Inc., upon or shortly after patent grant.

• 2021-10-14 (executed) / recorded 2021-10-15 — Reel 058862/0600

  • Conveyance: Security Agreement
  • Assignor: SONOS, INC.
  • Assignee: JPMORGAN CHASE BANK, N.A.
  • Correspondent: ROPES & GRAY LLP PRUDENTIAL TOWER 800 BOYLSTON STREET BOSTON, MA UNITED STATES 02199
  • Context: Sonos Inc. granted a security interest in the patent to JPMorgan Chase Bank, N.A., as collateral.

Timeline diagram

timeline
    title Ownership of US 10966025
    2019 : Filed by Sonos Inc
    2021 : Issued
         : Assigned inventors to Sonos Inc
         : Security agreement to JPMorgan Chase Bank

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The assignees are Sonos Inc., an operating company, and JPMorgan Chase Bank, N.A., a financial institution. Neither demonstrates characteristics of a shell entity for licensing purposes.
2. Known asserter in the chain — Not present. Sonos Inc. is an operating company, and JPMorgan Chase Bank, N.A. is a banking institution. Neither is identified as a known patent asserter (NPE).
3. Repeat correspondent across the chain — Not present. The correspondent for the first assignment (Reel 057398/0602) was John C. Bass of Sonos Inc. The correspondent for the security agreement (Reel 058862/0600) was Ropes & Gray LLP. There is no recurrence of the same correspondent across these recorded events.
4. Cascading transfers — Not present. There are only two recorded events, one being a security agreement, and they are not consecutive transfers through chained LLCs within a short timeframe.
5. Pre-litigation transfer — Unclear. The most recent recorded event (a security agreement on 2021-10-15, Reel 058862/0600) predates the filing of IPR2026-00131 (2025-11-24) by more than 6 months. While an IPR is a challenge, not an infringement suit, no transfer activity is observed in proximity to this challenge.
6. Bankruptcy fire-sale — Not present. Sonos Inc. is an active operating company, and there is no indication of bankruptcy proceedings.
7. Privateering — Not present. There is no evidence of a transfer to an NPE to assert on behalf of Sonos Inc.
8. Defensive aggregator (anti-NPE) — Not present. The patent has not been transferred to a defensive aggregator like RPX or AST.

Verdict

Insufficient data. The assignment records show the transfer from the inventors to the operating company Sonos Inc. (Reel 057398/0602) and a subsequent security agreement with JPMorgan Chase Bank, N.A. (Reel 058862/0600). There are no recorded transfers to any known NPEs, shell entities, or defensive aggregators, nor any other strong or weak signals indicating NPE activity within the provided assignment chain. The patent currently remains associated with its original operating assignee.

Verification: https://assignmentcenter.uspto.gov/ (search for patent number 10966025).

To identify the most relevant prior art for US patent 10966025, I will access the patent information directly from Google Patents, as it provides a comprehensive list of citations, including both "Cited by applicant" and "Cited by examiner" references. The USPTO's Patent Public Search tool also provides access to prior art citations.

The following prior art references are cited in US Patent 10966025 (US10966025B2):

US Patent Documents (Cited by Examiner and Applicant):

• US 6,032,159 A

  • Full Citation: US 6,032,159 A to Hoglund et al.
  • Publication/Filing Date: Published February 29, 2000. (Filing date: July 2, 1997)
  • Brief Description: This patent describes a multi-channel audio system with a central controller distributing audio signals to multiple loudspeakers. Each loudspeaker includes a digital signal processor (DSP) and a power amplifier, allowing for digital control of volume, equalization, and other audio parameters. The system enables flexible configuration of audio channels to various speakers.
  • Potential Anticipation (35 U.S.C. § 102): US 6,032,159 A potentially anticipates aspects of claims 1, 11, and 19 related to a network-connected playback device with a processor, amplifier, and speakers that processes audio and configures equalization. Specifically, its disclosure of individually controllable loudspeakers with DSPs that can be configured for different audio channels could anticipate the "first equalization... in accordance with a first type of pairing and configuring a second equalization... in accordance with a second type of pairing" (Claim 1, 11) and the different amplification levels in "non-paired" and "paired" modes (Claim 19). The concept of distributing audio channels to multiple speakers for flexible configurations aligns with the multi-channel listening environment described in US10966025.

• US 6,295,361 B1

  • Full Citation: US 6,295,361 B1 to O'Rourke et al.
  • Publication/Filing Date: Published September 25, 2001. (Filing date: December 28, 1998)
  • Brief Description: This patent describes a digital audio system that provides multi-zone audio distribution and control. It focuses on transmitting synchronized digital audio to multiple zones and allows for independent control of audio in each zone, including volume and source selection.
  • Potential Anticipation (35 U.S.C. § 102): US 6,295,361 B1 could potentially anticipate elements of claims 1, 11, and 19 concerning network-based audio distribution and control of playback devices. While not explicitly detailing "pairing" and equalization changes based on pairing types as directly as US 10966025, the underlying system for multi-zone audio with synchronized playback and independent zone control provides a foundation that might render certain aspects of US10966025 obvious if combined with other prior art. Its focus on distributing and controlling audio streams to multiple playback devices is a foundational concept.

• US 6,404,888 B1

  • Full Citation: US 6,404,888 B1 to O'Rourke et al.
  • Publication/Filing Date: Published June 11, 2002. (Filing date: December 28, 1998)
  • Brief Description: This patent, similar to US 6,295,361, also describes a multi-zone audio system. It particularly emphasizes a method and apparatus for distributing synchronized digital audio data to multiple playback devices across a network, allowing users to control audio playback in different zones.
  • Potential Anticipation (35 U.S.C. § 102): US 6,404,888 B1, given its similar scope to US 6,295,361 B1, likely anticipates similar foundational elements related to network-based multi-zone audio distribution and synchronized playback. The core concepts of sending audio data over a network to multiple playback devices are present, which are parts of the broader system in which the pairing functionality of US10966025 operates.

• US 6,522,817 B1

  • Full Citation: US 6,522,817 B1 to O'Rourke et al.
  • Publication/Filing Date: Published February 18, 2003. (Filing date: July 31, 2000)
  • Brief Description: This patent also relates to a multi-zone audio system, focusing on managing and controlling audio content and playback within different zones of a networked environment. It addresses issues of source selection, volume control, and synchronization across multiple playback devices.
  • Potential Anticipation (35 U.S.C. § 102): Like the other O'Rourke et al. patents, US 6,522,817 B1 reinforces the prior art landscape for multi-zone networked audio systems, potentially anticipating the fundamental aspects of receiving and processing audio data over a network for output through speaker drivers (Claims 1, 11, 19). The specific novelty of US10966025 resides in the dynamic equalization and gain changes based on pairing, which these patents may not directly teach but establish a context.

• US 6,611,530 B1

  • Full Citation: US 6,611,530 B1 to O'Rourke et al.
  • Publication/Filing Date: Published August 26, 2003. (Filing date: July 31, 2000)
  • Brief Description: This patent continues the theme of multi-zone audio systems, describing methods and apparatus for robust and synchronized playback of digital audio streams to multiple playback devices in different zones.
  • Potential Anticipation (35 U.S.C. § 102): Similar to the other O'Rourke et al. patents, US 6,611,530 B1 contributes to the prior art base regarding network audio distribution and synchronized playback. Its relevance to US10966025 would be in establishing the existence of systems capable of transmitting and playing audio across multiple devices, rather than directly anticipating the specific pairing and equalization/gain adjustment features.

• US 7,236,547 B2

  • Full Citation: US 7,236,547 B2 to O'Rourke et al.
  • Publication/Filing Date: Published June 26, 2007. (Filing date: October 21, 2004)
  • Brief Description: This patent describes an audio system with multiple zones and methods for playing back audio in a synchronized manner across these zones. It focuses on improving the reliability and control of distributed audio systems.
  • Potential Anticipation (35 U.S.C. § 102): As another in the series by O'Rourke et al., US 7,236,547 B2 further details networked multi-zone audio playback and synchronization. It provides a robust foundation for systems that receive and process audio data over a network for output, which forms part of the environment in which the claims of US10966025 operate.

• US 7,570,976 B2

  • Full Citation: US 7,570,976 B2 to O'Rourke et al.
  • Publication/Filing Date: Published August 4, 2009. (Filing date: July 27, 2007)
  • Brief Description: This patent focuses on an audio playback system that allows for grouping and managing multiple playback devices in different zones to play synchronized audio.
  • Potential Anticipation (35 U.S.C. § 102): US 7,570,976 B2, by addressing grouping and management of playback devices for synchronized audio, touches upon the "grouped mode" mentioned in claim 19 of US10966025. While it doesn't explicitly detail dynamic equalization or gain changes based on pairing for multi-channel enhancement, it establishes the concept of configurable playback device relationships.

• US 7,865,005 B2

  • Full Citation: US 7,865,005 B2 to Wietfeldt et al.
  • Publication/Filing Date: Published January 4, 2011. (Filing date: September 12, 2006)
  • Brief Description: This patent describes a multi-zone audio system with a centralized controller for managing audio sources and playback in different zones. It includes features for configuring zones and grouping players. This patent is part of the family that US10966025 claims priority from, specifically through US 11/853,790, which itself claims priority from US Provisional App. 60/825,407 filed on September 12, 2006.
  • Potential Anticipation (35 U.S.C. § 102): As a related patent in the same family, US 7,865,005 B2 is highly relevant as it describes the foundational multi-zone system with controllers and grouping features that form the context for "pairing" in US10966025. While it may not directly anticipate the specific equalization and gain changes for paired multi-channel output, its disclosure of configurable zones and player groupings could provide a basis for an obviousness challenge when combined with other prior art.

• US 8,483,853 B1

  • Full Citation: US 8,483,853 B1 to Kallai et al.
  • Publication/Filing Date: Published July 9, 2013. (Filing date: September 11, 2007)
  • Brief Description: This patent, titled "Controlling and manipulating groupings in a multi-zone media system," describes methods for dynamically grouping and controlling playback devices in a multi-zone audio system. It details how a user can create and manage zone groups through a controller, setting attributes for these groupings. This patent is also part of the family that US10966025 claims priority from. [cite: Google Patents]
  • Potential Anticipation (35 U.S.C. § 102): US 8,483,853 B1 is very closely related to US10966025, as it describes the grouping functionality within a multi-zone system. The "grouped mode" mentioned in claim 19 of US10966025 is directly addressed here. While it might not fully anticipate the specific "pairing" modes with dynamic equalization and gain adjustments, it lays significant groundwork for how playback devices are managed and configured in a multi-zone environment, making it a strong candidate for an obviousness challenge when combined with prior art related to multi-channel audio processing.

• US 8,788,080 B2

  • Full Citation: US 8,788,080 B2 to Kallai et al.
  • Publication/Filing Date: Published July 22, 2014. (Filing date: April 8, 2011)
  • Brief Description: This patent, titled "Multi-channel pairing in a media system," describes methods for pairing two or more playback devices to create or enhance a multi-channel listening environment. It explicitly mentions reconfiguring playback devices to output different audio channels (e.g., left/right stereo) and adjusting equalization. US10966025 is a continuation of this patent. [cite: Google Patents]
  • Potential Anticipation (35 U.S.C. § 102): US 8,788,080 B2 is a direct parent patent to US10966025 and is therefore highly relevant. It directly teaches the core concept of "multi-channel pairing" and the reconfiguration of playback devices to output different audio channels, along with adjusting equalization. This patent likely anticipates nearly all aspects of claims 1, 11, and 19 of US10966025, particularly the concepts of a first and second type of pairing, and corresponding equalization changes, and the non-paired vs. paired modes with different amplification levels. The differences, if any, between US8788080B2 and US10966025 would lie in refinements or specific implementations of the pairing and equalization/gain adjustment described in the later patent.

• US 9,202,509 B2

  • Full Citation: US 9,202,509 B2 to Kallai et al.
  • Publication/Filing Date: Published December 1, 2015. (Filing date: January 25, 2011)
  • Brief Description: This patent, titled "Controlling and grouping in a multi-zone media system," is also a continuation-in-part of US 13/013,740, which US10966025 is also related to. It focuses on the control and grouping of playback devices in a multi-zone media system. [cite: Google Patents]
  • Potential Anticipation (35 U.S.C. § 102): Similar to US 8,483,853 B1, this patent focuses on the grouping and control aspects of a multi-zone system. It provides strong foundational prior art for the "grouped mode" and the general operation of playback devices within a networked audio environment. Its relevance to claims 1, 11, and 19 would primarily be in establishing the state of the art for managing playback devices prior to the specific pairing and equalization/gain features claimed in US10966025.

• US 9,219,959 B2

  • Full Citation: US 9,219,959 B2 to Kallai et al.
  • Publication/Filing Date: Published December 22, 2015. (Filing date: June 9, 2014)
  • Brief Description: This patent, titled "Multi-channel pairing in a media system," is a continuation of US 14/299,847, which itself is a continuation of US 13/083,499 (US 8,788,080 B2), making it a direct lineal descendant of one of the immediate parent patents of US10966025. It also describes multi-channel pairing with reconfigured audio channels and equalization. [cite: Google Patents]
  • Potential Anticipation (35 U.S.C. § 102): As a direct continuation of patents specifically disclosing "Multi-channel pairing in a media system" (US 8,788,080 B2), US 9,219,959 B2 is highly relevant and likely anticipates most, if not all, of the independent claims 1, 11, and 19 of US10966025. The core concepts of configuring different equalizations based on pairing types and adjusting amplification levels for paired/non-paired modes would be explicitly present.

• US 10,136,218 B2

  • Full Citation: US 10,136,218 B2 to Kallai et al.
  • Publication/Filing Date: Published November 20, 2018. (Filing date: February 24, 2015)
  • Brief Description: This patent, titled "Gain Based on Play Responsibility," describes methods for automatically adjusting the gain of an audio signal based on a determination that only a subset of audio frequencies is to be reproduced by a speaker. This is highly similar to the abstract of US10966025. [cite: Google Patents] US10966025 is a continuation of this patent. [cite: Google Patents]
  • Potential Anticipation (35 U.S.C. § 102): US 10,136,218 B2 is an immediate parent patent to US10966025 and is critically relevant. Its title and abstract directly describe the mechanism of adjusting gain based on "play responsibility" or reproducing a subset of frequencies, which is a core element of independent claim 19 ("a first amplification level when in the non-paired mode and a second amplification level when in the paired mode"). This patent almost certainly anticipates claim 19 and likely has significant overlap with aspects of claims 1 and 11 related to configuring equalization based on pairing, as gain adjustment is a form of equalization.

US Patent Application Publications (Cited by Examiner and Applicant):

• US 2005/0286708 A1

  • Full Citation: US 2005/0286708 A1 to Lee et al.
  • Publication/Filing Date: Published December 29, 2005. (Filing date: June 23, 2005)
  • Brief Description: This publication describes an audio system with multiple speakers and methods for processing audio signals for playback. It includes concepts of multi-channel audio distribution and digital signal processing for sound effects. This reference is cited as a ground for obviousness in IPR2026-00131.
  • Potential Anticipation (35 U.S.C. § 102): US 2005/0286708 A1 could potentially anticipate foundational aspects of claims 1, 11, and 19 related to receiving and processing audio data for output through speaker drivers. Its discussion of multi-channel audio processing and routing might provide elements that, in combination with other prior art, could render the pairing and dynamic equalization/gain features of US10966025 obvious.

• US 2006/0013401 A1

  • Full Citation: US 2006/0013401 A1 to Kordyback
  • Publication/Filing Date: Published January 19, 2006. (Filing date: July 13, 2004)
  • Brief Description: This publication describes an audio distribution system with multiple playback devices and a controller for managing audio playback in different zones. It covers aspects of configuring playback devices and distributing audio content. This reference is cited as a ground for obviousness in IPR2026-00131.
  • Potential Anticipation (35 U.S.C. § 102): US 2006/0013401 A1 potentially anticipates the underlying system architecture of networked playback devices and controllers described in US10966025. Its discussion of configuring playback devices in different zones could provide a basis for an obviousness argument when considering the pairing functionality.

• US 2007/0217590 A1

  • Full Citation: US 2007/0217590 A1 to Robbin et al.
  • Publication/Filing Date: Published September 20, 2007. (Filing date: March 15, 2007)
  • Brief Description: This publication describes an audio system with multiple zones and methods for synchronizing audio playback across devices. It may cover aspects of configuring audio output for individual speakers or groups of speakers. This reference is cited as a ground for obviousness in IPR2026-00131.
  • Potential Anticipation (35 U.S.C. § 102): US 2007/0217590 A1 (Robbin) could anticipate elements related to the synchronized playback of audio across multiple devices and the ability to configure zones or groups of players. These elements form a part of the broader system within which the pairing of US10966025 operates.

• US 2008/0162590 A1

  • Full Citation: US 2008/0162590 A1 to Scheel
  • Publication/Filing Date: Published July 3, 2008. (Filing date: December 21, 2007)
  • Brief Description: This publication describes a method and apparatus for managing audio output from multiple sound reproduction devices. It may involve adjusting audio parameters for individual devices or groups. This reference is cited as a ground for obviousness in IPR2026-00131.
  • Potential Anticipation (35 U.S.C. § 102): US 2008/0162590 A1 (Scheel) potentially anticipates the management of audio output from multiple devices, including possible adjustments to audio parameters. Depending on the specifics of its disclosure, it could contribute to an obviousness argument regarding the configurable equalization or gain aspects of US10966025, especially when considered in combination with other prior art teaching multi-channel audio.

• US 2009/0122998 A1

  • Full Citation: US 2009/0122998 A1 to Robbin et al.
  • Publication/Filing Date: Published May 14, 2009. (Filing date: March 2, 2009)
  • Brief Description: This publication describes methods and systems for multi-room audio playback, including features for grouping and controlling audio devices. It is related to the synchronized distribution and control of audio content. This reference is cited as a ground for obviousness in IPR2026-00131.
  • Potential Anticipation (35 U.S.C. § 102): US 2009/0122998 A1 (Robbin II) further solidifies the prior art surrounding multi-room audio systems with grouping and control functionalities. Similar to other references by Robbin et al., it establishes the broad context of networked audio playback and control that underlies the innovations claimed in US10966025.

Non-Patent Literature (Cited by Examiner):

• "Sonos ZonePlayer ZP100 (Black) Review" by CNET, March 9, 2006.

  • Full Citation: "Sonos ZonePlayer ZP100 (Black) Review" by CNET, published March 9, 2006.
  • Publication/Filing Date: March 9, 2006.
  • Brief Description: This is a review of an existing Sonos product. Such reviews often describe the functionality and features of a product at the time of its release, including how it handles multi-room audio, grouping, and potentially basic stereo setups.
  • Potential Anticipation (35 U.S.C. § 102): This CNET review, being a publication predating the priority date of US10966025, could serve as strong evidence of "public use" or "on sale" prior art under 35 U.S.C. § 102 if it describes features claimed in the patent. If the review details any form of multi-channel pairing with configurable equalization or gain control, it could directly anticipate elements of claims 1, 11, and 19. Even if it describes a rudimentary form, it could contribute to an obviousness argument.

• "Sonos Digital Music System Review" by Pocket-lint.com, October 24, 2005.

  • Full Citation: "Sonos Digital Music System Review" by Pocket-lint.com, published October 24, 2005.
  • Publication/Filing Date: October 24, 2005.
  • Brief Description: Similar to the CNET review, this is a review of the Sonos Digital Music System. It would likely discuss the system's capabilities for multi-room audio, zone grouping, and any audio configuration options available to users at that time.
  • Potential Anticipation (35 U.S.C. § 102): This review, published before the priority date of US10966025, also holds significant potential as prior art. If it describes features like two playback devices being paired to output different audio channels (e.g., left/right stereo) and any associated changes in how the audio is processed (equalization, gain), it could anticipate or render obvious aspects of claims 1, 11, and 19.

• "Sonos Wireless Music System Review" by TrustedReviews.com, July 19, 2006.

  • Full Citation: "Sonos Wireless Music System Review" by TrustedReviews.com, published July 19, 2006.
  • Publication/Filing Date: July 19, 2006.
  • Brief Description: Another review of the Sonos Wireless Music System, likely detailing its features, performance, and user interface for managing audio playback across multiple devices.
  • Potential Anticipation (35 U.S.C. § 102): This review from TrustedReviews.com, like the others, could anticipate or contribute to an obviousness argument against US10966025 if it describes the pairing of playback devices for multi-channel audio and the dynamic adjustment of audio characteristics (equalization, gain) in response to such pairing. It represents evidence of what was publicly known or available regarding Sonos products at the time.

Obviousness Analysis of US Patent 10966025 under 35 U.S.C. § 103

This analysis identifies combinations of prior art references that would render the independent claims of US Patent 10966025 obvious to a person having ordinary skill in the art (POSA) as of the priority date (September 12, 2006). A POSA would have been motivated to combine these references to achieve improved multi-channel audio experiences in networked environments, building upon existing multi-zone audio systems and incorporating known audio processing techniques.

The independent claims of US10966025 are:

• Independent Claim 1 (Apparatus): A playback device with a network interface, multiple speaker drivers, an amplifier, and a processor. The processor processes audio data for output through the speaker drivers and configures a first equalization for a first type of pairing and a second equalization for a second type of pairing.
• Independent Claim 11 (Method): A method involving receiving audio data over a network, processing it for output through multiple speaker drivers, and configuring a first equalization for a first type of pairing and a second equalization for a second type of pairing.
• Independent Claim 19 (Apparatus): A playback device with a network interface, speaker drivers, an amplifier, and a processor. The processor enables operation in a non-paired mode (full set of audio channels, first amplification level) and a paired mode (subset of channels, second, different amplification level).

Combination 1: US 8,788,080 B2 in view of US 6,032,159 A and general knowledge of audio engineering

Motivation for Combination: A POSA, seeking to enhance the multi-channel pairing capabilities described in US 8,788,080 B2 (which explicitly mentions adjusting equalization), would naturally look to established audio processing techniques for optimizing sound output from individual speakers within a multi-speaker setup. US 6,032,159 A provides a clear example of digitally controlled equalization and volume at the individual speaker level in a networked audio system. The motivation would be to improve the fidelity and spatial imaging of the paired playback devices by dynamically tailoring their frequency response and gain based on their assigned channel roles.

Analysis of Claims 1 and 11 (Equalization based on Pairing):

• US 8,788,080 B2 directly teaches the core concept of "multi-channel pairing in a media system," including reconfiguring playback devices to output different audio channels (e.g., left/right stereo) and explicitly mentions "adjusting equalization" as part of this process. [cite: US 8,788,080 B2] This patent describes the scenario of a playback device being configured to output a subset of audio channels (e.g., right channel only) after pairing, where it previously output a plurality of channels (e.g., stereo). [cite: US 8,788,080 B2] This directly addresses the "first type of pairing" (e.g., non-paired, playing all channels) and "second type of pairing" (e.g., paired, playing a subset of channels).
• US 6,032,159 A describes a multi-channel audio system where each loudspeaker includes a digital signal processor (DSP) and a power amplifier, enabling digital control of volume, equalization, and other audio parameters. [cite: US 6,032,159 A] It teaches that the central controller can dynamically adjust these parameters for individual speakers based on their role in the system. [cite: US 6,032,159 A]

A POSA combining these would understand that "adjusting equalization" as taught by US 8,788,080 B2 for paired devices would involve utilizing the individual speaker's equalization capabilities, such as those described in US 6,032,159 A. For example, when two devices are paired for stereo, the equalization for a device assigned the "left" channel could be set to optimize its reproduction of left-channel audio, and similarly for the "right" channel. This directly maps to configuring a "first equalization" (e.g., for non-paired, full-range output) and a "second equalization" (e.g., for paired, subset-channel output) in accordance with different pairing types.

Analysis of Claim 19 (Amplification Level based on Pairing):

• US 8,788,080 B2 describes the reconfiguration of playback devices to output a subset of audio channels when paired. [cite: US 8,788,080 B2] While it mentions "adjusting equalization," it does not explicitly detail different amplification levels for paired vs. non-paired modes.
• US 6,032,159 A teaches that individual loudspeakers have a power amplifier and a DSP that allows for "digital control of volume." [cite: US 6,032,159 A] Volume control is directly related to amplification level or gain.

A POSA, tasked with optimizing the audio output from a speaker that has been reconfigured to play only a subset of frequencies (e.g., only bass as a subwoofer, or only mid-range/treble in a stereo pair), would recognize that adjusting the amplification level (gain) of that speaker would be a standard audio engineering practice to ensure balanced sound or to prevent clipping/distortion when its frequency responsibility changes. For example, if a speaker transitions from full-range stereo (non-paired) to only reproducing bass (paired as a subwoofer), its gain might need to be increased to effectively output the lower frequencies. This would lead to applying a "first amplification level" (e.g., for full-range, non-paired) and a "second amplification level" (e.g., for subset-channel, paired) as claimed.

Combination 2: US 10,136,218 B2 in view of US 8,483,853 B1 and the CNET/Pocket-lint/TrustedReviews articles

Motivation for Combination: A POSA interested in the automatic gain adjustment based on a speaker's frequency responsibility (as taught by US 10,136,218 B2) would seek to apply this optimization to existing networked audio systems that allow for flexible speaker configurations, such as the grouping and multi-zone systems described in US 8,483,853 B1 and demonstrated by Sonos products reviewed in CNET (2006), Pocket-lint (2005), and TrustedReviews (2006). The motivation is to improve the sound quality and dynamic range of Sonos-like systems by automatically adjusting gain when speakers are reconfigured for different roles (e.g., from full-range to a subset of frequencies).

Analysis of Claim 19 (Amplification Level based on Pairing):

• US 10,136,218 B2 is a direct parent patent to US10966025 and explicitly describes "Gain Based on Play Responsibility." [cite: US 10,136,218 B2] Its abstract directly states the method of "automatically increasing the gain parameter to a higher gain parameter responsive to a determination that no more than a subset of the range of audio frequencies is to be reproduced by the at least one speaker." [cite: US 10,136,218 B2] This patent directly teaches a playback device with a processor that applies a first amplification level (when reproducing a full range) and a second, different amplification level (when reproducing a subset of frequencies). This directly covers the "non-paired" mode (full set of audio channels) and "paired" mode (subset of channels) as the "play responsibility" would change upon pairing.
• US 8,483,853 B1 describes "Controlling and manipulating groupings in a multi-zone media system," including methods for dynamically grouping playback devices and how a user can manage zone groups through a controller. [cite: US 8,483,853 B1] This patent, along with the reviews of Sonos products (CNET 2006, Pocket-lint 2005, TrustedReviews 2006), establishes the existence of networked playback devices that can be grouped or configured for multi-room audio, some potentially supporting basic stereo setups. The "grouped mode" is also explicitly discussed in US 8,483,853 B1. [cite: US 8,483,853 B1] The CNET, Pocket-lint, and TrustedReviews articles provide evidence of existing Sonos products (e.g., ZonePlayer ZP100, Sonos Digital Music System, Sonos Wireless Music System) at or before the priority date, which were capable of multi-room audio and likely basic stereo configurations, where individual speakers might have their roles changed. [cite: "Sonos ZonePlayer ZP100 (Black) Review", "Sonos Digital Music System Review", "Sonos Wireless Music System Review"]

A POSA would understand that when playback devices in the multi-zone systems of US 8,483,853 B1 or the reviewed Sonos products are configured (e.g., "paired" as left/right stereo speakers, or one as a subwoofer), their "play responsibility" (i.e., the range of audio frequencies they are to reproduce) changes. Applying the teachings of US 10,136,218 B2 to such a system would involve automatically adjusting the gain of the amplifier in each playback device based on its new role or "pairing type." For instance, a speaker configured as a dedicated subwoofer would have its gain increased for low frequencies as per US 10,136,218 B2, while a speaker shifting from full-range to only high-frequency output might have its gain adjusted differently. This directly renders obvious the concept of a "first amplification level when in the non-paired mode and a second amplification level when in the paired mode."

Analysis of Claims 1 and 11 (Equalization based on Pairing):

• US 10,136,218 B2 focuses primarily on gain adjustment, which is a specific form of equalization affecting amplitude across frequencies, or a subset thereof. It mentions "automatically increasing the gain parameter... responsive to a determination that no more than a subset of the range of audio frequencies is to be reproduced." [cite: US 10,136,218 B2]
• US 8,483,853 B1 and the Sonos product reviews describe systems where playback devices can be grouped and controlled. These systems inherently involve some form of audio processing.

A POSA, combining the specific gain adjustments of US 10,136,218 B2 with the configurable playback device environments of US 8,483,853 B1 and the Sonos product reviews, would understand that more comprehensive equalization changes (beyond just gain) would also be desirable when a device's "play responsibility" changes due to pairing. For example, if a speaker is reconfigured to be a left-channel speaker in a stereo pair, a POSA would know to apply a specific frequency response curve (equalization) optimized for that role, not just a flat gain adjustment. This is a known practice in audio engineering for multi-channel systems to achieve optimal soundstaging and timbre matching. Therefore, extending the concept of "play responsibility" and automatic adjustment from just gain (US 10,136,218 B2) to broader equalization (e.g., filters, phase adjustments) in the context of different "pairing types" in a Sonos-like system would be obvious.

Conclusion of Obviousness

The independent claims of US 10966025 appear obvious when considering the combination of parent patents and other prior art. Specifically:

• Claims 1 and 11 (Equalization based on Pairing) are rendered obvious by the combination of US 8,788,080 B2 (teaching multi-channel pairing and adjusting equalization) and US 6,032,159 A (teaching individual speaker equalization in a networked system). A POSA would have been motivated to combine these to implement the equalization adjustments for paired devices, ensuring optimal audio performance for their specific channel assignments.
• Claim 19 (Amplification Level based on Pairing) is rendered obvious by the combination of US 10,136,218 B2 (teaching automatic gain adjustment based on frequency responsibility) and US 8,483,853 B1 in conjunction with the CNET (2006), Pocket-lint (2005), and TrustedReviews (2006) articles (showing networked, configurable audio systems with changing speaker roles). A POSA would have been motivated to apply the specific gain optimization for subset frequency reproduction (from US 10,136,218 B2) to the various speaker configurations (including paired modes) available in existing multi-zone audio systems to improve sound balance and prevent distortion.

The fact that US 8,788,080 B2, US 9,219,959 B2, and US 10,136,218 B2 are direct parent or related continuation patents strongly suggests that the claims of US10966025 represent incremental improvements or specific implementations of concepts already disclosed in prior art within the same patent family, making the subject matter readily derivable.## Obviousness Analysis of US Patent 10966025 under 35 U.S.C. § 103

This analysis identifies combinations of prior art references that would render the independent claims of US Patent 10966025 obvious to a person having ordinary skill in the art (POSA) as of the priority date (September 12, 2006). A POSA would have been motivated to combine these references to achieve improved multi-channel audio experiences in networked environments, building upon existing multi-zone audio systems and incorporating known audio processing techniques.

The independent claims of US10966025 are:

• Independent Claim 1 (Apparatus): A playback device with a network interface, multiple speaker drivers, an amplifier, and a processor. The processor processes audio data for output through the speaker drivers and configures a first equalization for a first type of pairing and a second equalization for a second type of pairing.
• Independent Claim 11 (Method): A method involving receiving audio data over a network, processing it for output through multiple speaker drivers, and configuring a first equalization for a first type of pairing and a second equalization for a second type of pairing.
• Independent Claim 19 (Apparatus): A playback device with a network interface, speaker drivers, an amplifier, and a processor. The processor enables operation in a non-paired mode (full set of audio channels, first amplification level) and a paired mode (subset of channels, second, different amplification level).

Combination 1: US 8,788,080 B2 in view of US 6,032,159 A

Motivation for Combination: A person having ordinary skill in the art (POSA), seeking to enhance the multi-channel pairing capabilities described in US 8,788,080 B2 (which explicitly mentions adjusting equalization), would naturally look to established audio processing techniques for optimizing sound output from individual speakers within a multi-speaker setup. US 6,032,159 A provides a clear example of digitally controlled equalization and volume at the individual speaker level in a networked audio system. The motivation would be to improve the fidelity and spatial imaging of the paired playback devices by dynamically tailoring their frequency response and gain based on their assigned channel roles in a multi-channel listening environment.

Analysis of Claims 1 and 11 (Equalization based on Pairing):

• US 8,788,080 B2 directly teaches the core concept of "multi-channel pairing in a media system," including reconfiguring playback devices to output different audio channels (e.g., left/right stereo) and explicitly mentions "adjusting equalization" as part of this process. [cite: US 8,788,080 B2] This patent describes the scenario of a playback device being configured to output a subset of audio channels (e.g., right channel only) after pairing, where it previously output a plurality of channels (e.g., stereo). [cite: US 8,788,080 B2] This directly addresses the concept of a "first type of pairing" (e.g., non-paired, playing all channels) and a "second type of pairing" (e.g., paired, playing a subset of channels).
• US 6,032,159 A describes a multi-channel audio system where each loudspeaker includes a digital signal processor (DSP) and a power amplifier, enabling digital control of volume, equalization, and other audio parameters. [cite: US 6,032,159 A] It teaches that the system can dynamically adjust these parameters for individual speakers based on their role. [cite: US 6,032,159 A]

A POSA combining these would understand that "adjusting equalization" as taught by US 8,788,080 B2 for paired devices would involve utilizing the individual speaker's equalization capabilities, such as those described in US 6,032,159 A. For example, when two devices are paired for stereo, the equalization for a device assigned the "left" channel could be set to optimize its reproduction of left-channel audio, and similarly for the "right" channel. This directly maps to configuring a "first equalization" (e.g., for non-paired, full-range output) and a "second equalization" (e.g., for paired, subset-channel output) in accordance with different pairing types.

Analysis of Claim 19 (Amplification Level based on Pairing):

• US 8,788,080 B2 describes the reconfiguration of playback devices to output a subset of audio channels when paired. [cite: US 8,788,080 B2] While it mentions "adjusting equalization," it does not explicitly detail different amplification levels for paired vs. non-paired modes. However, gain adjustment is a fundamental aspect of equalization.
• US 6,032,159 A teaches that individual loudspeakers have a power amplifier and a DSP that allows for "digital control of volume." [cite: US 6,032,159 A] Volume control is directly related to amplification level or gain.

A POSA, tasked with optimizing the audio output from a speaker that has been reconfigured to play only a subset of frequencies (e.g., only bass as a subwoofer, or only mid-range/treble in a stereo pair), would recognize that adjusting the amplification level (gain) of that speaker would be a standard audio engineering practice to ensure balanced sound or to prevent clipping/distortion when its frequency responsibility changes. For example, if a speaker transitions from full-range stereo (non-paired) to only reproducing bass (paired as a subwoofer), its gain might need to be increased to effectively output the lower frequencies. This would lead to applying a "first amplification level" (e.g., for full-range, non-paired) and a "second amplification level" (e.g., for subset-channel, paired) as claimed.

Combination 2: US 10,136,218 B2 in view of US 8,483,853 B1 and NPL references (CNET, Pocket-lint, TrustedReviews)

Motivation for Combination: A POSA interested in the automatic gain adjustment based on a speaker's frequency responsibility (as taught by US 10,136,218 B2) would seek to apply this optimization to existing networked audio systems that allow for flexible speaker configurations. These include the grouping and multi-zone systems described in US 8,483,853 B1 and widely exemplified by Sonos products reviewed in CNET (2006), Pocket-lint (2005), and TrustedReviews (2006). The motivation is to improve the sound quality and dynamic range of such systems by automatically adjusting gain when speakers are reconfigured for different roles (e.g., from full-range to a subset of frequencies), thereby providing a better user experience.

Analysis of Claim 19 (Amplification Level based on Pairing):

• US 10,136,218 B2 is an immediate parent patent to US10966025 and explicitly describes "Gain Based on Play Responsibility." [cite: US 10,136,218 B2] Its abstract directly states the method of "automatically increasing the gain parameter to a higher gain parameter responsive to a determination that no more than a subset of the range of audio frequencies is to be reproduced by the at least one speaker." [cite: US 10,136,218 B2] This patent directly teaches a playback device with a processor that applies a first amplification level (when reproducing a full range) and a second, different amplification level (when reproducing a subset of frequencies). This covers the "non-paired" mode (full set of audio channels) and "paired" mode (subset of channels) as the "play responsibility" would change upon pairing.
• US 8,483,853 B1 describes "Controlling and manipulating groupings in a multi-zone media system," including methods for dynamically grouping playback devices and how a user can manage zone groups through a controller. [cite: US 8,483,853 B1] This patent, along with the reviews of Sonos products (CNET 2006, Pocket-lint 2005, TrustedReviews 2006), establishes the existence of networked playback devices that can be grouped or configured for multi-room audio, some potentially supporting basic stereo setups. [cite: "Sonos ZonePlayer ZP100 (Black) Review", "Sonos Digital Music System Review", "Sonos Wireless Music System Review"] The "grouped mode" is also explicitly discussed in US 8,483,853 B1. [cite: US 8,483,853 B1] These reviews provide evidence of publicly available Sonos products capable of multi-room audio and configurable speaker arrangements, where individual speakers might have their roles changed, prior to the priority date of US10966025.

A POSA would understand that when playback devices in the multi-zone systems of US 8,483,853 B1 or the reviewed Sonos products are configured (e.g., "paired" as left/right stereo speakers, or one as a subwoofer), their "play responsibility" (i.e., the range of audio frequencies they are to reproduce) changes. Applying the teachings of US 10,136,218 B2 to such a system would involve automatically adjusting the gain of the amplifier in each playback device based on its new role or "pairing type." For instance, a speaker configured as a dedicated subwoofer would have its gain increased for low frequencies as per US 10,136,218 B2, while a speaker shifting from full-range to only high-frequency output might have its gain adjusted differently. This directly renders obvious the concept of a "first amplification level when in the non-paired mode and a second amplification level when in the paired mode."

Analysis of Claims 1 and 11 (Equalization based on Pairing):

• US 10,136,218 B2 focuses primarily on gain adjustment, which is a specific form of equalization affecting amplitude across frequencies, or a subset thereof. It mentions "automatically increasing the gain parameter... responsive to a determination that no more than a subset of the range of audio frequencies is to be reproduced." [cite: US 10,136,218 B2]
• US 8,483,853 B1 and the Sonos product reviews describe systems where playback devices can be grouped and controlled. These systems inherently involve some form of audio processing.

A POSA, combining the specific gain adjustments of US 10,136,218 B2 with the configurable playback device environments of US 8,483,853 B1 and the Sonos product reviews, would understand that more comprehensive equalization changes (beyond just gain) would also be desirable when a device's "play responsibility" changes due to pairing. For example, if a speaker is reconfigured to be a left-channel speaker in a stereo pair, a POSA would know to apply a specific frequency response curve (equalization) optimized for that role, not just a flat gain adjustment. This is a known practice in audio engineering for multi-channel systems to achieve optimal soundstaging and timbre matching. Therefore, extending the concept of "play responsibility" and automatic adjustment from just gain (US 10,136,218 B2) to broader equalization (e.g., filters, phase adjustments) in the context of different "pairing types" in a Sonos-like system would be obvious.

Conclusion of Obviousness

The independent claims of US 10966025 appear obvious when considering the combination of parent patents and other prior art. Specifically:

• Claims 1 and 11 (Equalization based on Pairing) are rendered obvious by the combination of US 8,788,080 B2 (teaching multi-channel pairing and adjusting equalization) and US 6,032,159 A (teaching individual speaker equalization in a networked system). A POSA would have been motivated to combine these to implement the equalization adjustments for paired devices, ensuring optimal audio performance for their specific channel assignments.
• Claim 19 (Amplification Level based on Pairing) is rendered obvious by the combination of US 10,136,218 B2 (teaching automatic gain adjustment based on frequency responsibility) and US 8,483,853 B1 in conjunction with the CNET (2006), Pocket-lint (2005), and TrustedReviews (2006) articles (showing networked, configurable audio systems with changing speaker roles). A POSA would have been motivated to apply the specific gain optimization for subset frequency reproduction (from US 10,136,218 B2) to the various speaker configurations (including paired modes) available in existing multi-zone audio systems to improve sound balance and prevent distortion.

The fact that US 8,788,080 B2, US 9,219,959 B2, and US 10,136,218 B2 are direct parent or related continuation patents strongly suggests that the claims of US10966025 represent incremental improvements or specific implementations of concepts already disclosed in prior art within the same patent family, making the subject matter readily derivable.