In August 2020, Sonos and Lenbrook Industries reached an important settlement in Sonos’ patent infringement lawsuit against Lenbrook regarding the Bluesound wireless audio system. As a result of that settlement, Lenbrook signed a multi-year licensing deal, which has since allowed Bluesound and BluOS-enabled solutions to thrive worldwide by simply building over that foundation and exploring different market segments not addressed by Sonos.

A similar patent infringement deal was settled earlier with Sound United regarding the original Denon HEOS solutions (originated prior to Sound United taking control of Denon and Marantz, in 2017), which unfortunately didn't have the same positive outcome. The case dragged on for four years, and it was always a head-to-head confrontation that expanded from the key underlying technologies into accusations of marketing plagiarism. The terms of the agreement remain confidential, but the story is a great case study of bad strategy for future reference in the audio industry. Since those settlements, Sonos has continued to fight in court against Google to protect its wireless audio patents.

All those lawsuits basically targeted the original technology pioneered by Sonos since 2005. Before Sonos, there was only Apple, which gradually expanded the AirPlay ecosystem originated in 2004 from its AirTunes software but evolved in new directions to enable video, file transmission, and wireless screen sharing. Sonos' approach was targeted from the start toward point-to-multipoint streaming, and also differed in the fact that the company designed speakers and perfected the technology as a distributed audio-centric system, allowing a central hub of connected audio sources to stream wirelessly to multiple speakers around the home. And while Sonos was gradually building up its own home ecosystem, it also quickly built a strong portfolio of patents.

At the same time, multiple chip vendors and technology companies tried to follow suit, and improve on Sonos’ own implementation. Companies, such as Imagination Technologies with its CaskeID approach, were quickly followed by Qualcomm with its AllPlay solution, and DTS with Play-Fi, among others which have faded away. As many large consumer electronics companies faced the need to match Sonos’ features by licensing the technology, Google and Amazon also understood that it would be strategically important to offer the convenience of wireless home audio, and meet the growing demand. Both announced their own wireless audio streaming solutions, including multiroom features, while Sonos kept engaging with the two companies in an effort to implement support for their respective voice assistants.

In January 2020, Sonos revealed it was fighting in court against Google, which it accused of infringing on five of its wireless audio patents. And while the two companies worked together on Google Assistant voice features, Google started selling wireless speakers, which Sonos claimed infringed its core wireless audio patents. Predictably, Google countersued Sonos for any reason it could think off, including mesh networking and echo cancellation technology.

This would be a clear case where a quick settlement would have been the most beneficial solution for Google. Unfortunately, it didn't happen, and now in early January 2022, the US International Trade Commission has recognized Sonos’ claims that Google had infringed on its speaker and cast patents. This recognizes and highlights five key patents in wireless audio streaming to multiple speakers, which is key to multiroom, which means that it will become much harder in the future - even for very large organizations, such as Google or Amazon - to sell wireless speakers at cost if they need to add the required licenses to Sonos.

audioXpress mainly tracks and underscores innovations and technology breakthroughs in audio, and I am not going to make judgements on these legal disputes, which are usually way more complicated than it seems. We all know how very large corporations such as Google and Apple get irremediably entangled in permanent IP-infringing court cases - sometimes rightfully so, but in most of the cases simply pursued by predatory organizations created with the single purpose of profiting from settlements.

Some key audio patents are awarded every day, fortunately recognizing and awarding protection to pioneering research and development, and sometimes years of hard work long before anyone foresaw an opportunity. Others, are simply the result of the fact that patent language can be a tricky field on which to profit from even the most basic of concepts — and many patents seem so farfetched that they remain obscure until discovered by opportunistic players. Every day we see patents being published like that.

Just today I noticed a press release from ClearOne, a relatively small company from Salt Lake City, UT, specializing in conferencing and AV systems, which is clearly out of the radar in consumer electronics. The company has been building an important patent portfolio, which has already been noticed by larger competitors. In its latest patent, “Band-Limited Beamforming Microphone Array with Acoustic Echo Cancellation,” ClearOne was awarded key IP that I am certain will disturb ambitions for many companies working with similar concepts for totally different applications.

US Patent No. 11240598, issued on February 1, describes, among other things, "A microphone array with one set of microphones used for beamforming, and one or more additional microphones that are not used for beamforming, but instead are used to augment the audio performance of the microphone array." Sound familiar? Just think about ANC earbuds and virtually every single soundbar with voice recognition that needs to counteract environment noise. The patent also details that this beamforming microphone array includes acoustic echo cancellation.

On February 1, ClearOne was also awarded US Patent No. 11240597, relating broadly to "Ceiling Tile Beamforming Microphone Array System” claims. This describes "a ceiling tile microphone array that can be physically separated from the processors running the beamforming algorithm." A very specific development for conference rooms that is quite common in this type of installations - only now starting to migrate to distributed, on-device processing, and edge-AI.

And ClearOne was also recently awarded two new patents relating to Power-over-Ethernet (PoE) (US 11181959 and US 11188133), recognizing the company's IP on systems and methods for providing power to multiple devices in a novel “daisy-chain” configuration, intelligently allocating power distribution among these devices without disturbing the standard PoE handshaking protocol. There is no doubt that these patents recognize the merit of the company's efforts in its field, but sooner or later someone will stumble upon their IP when trying to design a novel approach in many promising and emerging applications.

This was already the case for some of the largest microphone companies that were in the market previously with ceiling mic arrays for conference applications. In November 4, 2021, ClearOne received a positive verdict in a Delaware court that its "Ceiling Tile Beamforming Mic Array" line of products do not infringe on a patent from Shure. This case was filed after ClearOne originally sued Shure to prevent it from “manufacturing, marketing, and selling” its own array microphones in its “drop-ceiling mounting configuration.” The source of dispute being ClearOne's original beamforming microphone array audio conferencing system, introduced in 2012.

ClearOne has aggressively defended its product range, going as far as impeding other manufacturers from offering similar ceiling tile mounting frames that allow these microphones to be fitted in standard ceiling tile structures.

In an increasingly interoperability dependent environment, such as corporate, commercial, and residential integrations systems, where the major players such as Shure, Sennheiser, QSC, or Biamp frequently forge strategic alliances, this strategy isn't working very well for ClearOne in its intended market. But of course, this might be a totally different story if these patents fall into the hands of patent trolls.

A way for companies to gain an advantage in dealing with these technology constraints is to engage and accelerate the development of specifications and standards. And for some small companies, this means engaging early in unique opportunities, such as the recent efforts in the Bluetooth LE Audio specification. Such was the case for many of the companies that I met at CES 2020, when the Bluetooth Special Interest Group (SIG) announced LE Audio, the next generation of Bluetooth audio.

Among those companies was T2 Software (formerly T2 Labs), a small venture from Louisville, KY, which was the first company to fully qualify all of the adopted profiles and services supporting Bluetooth LE Audio. In September 2021, T2 saw its Bluetooth LE Audio Host Stack qualified by the Bluetooth SIG. This LE Audio qualification was in addition to past qualifications for a full Dual Mode Host Stack and LC3. T2 Software has been an active participant in the Bluetooth LE Audio working groups within the Bluetooth SIG and focused completely on Bluetooth Audio software development, and providing embedded wireless software development for OEM manufacturers. Originally, T2 ported its LE Audio Host Stack and LC3 codec support for the Synopsys ARC EM processor family.

In November 2021, T2 Software was acquired by Sonos, and its core team, Tim Reilly, Tim Thomas, and Michael Rougeux, are now all leading software engineering efforts for Sonos. The original t2software.com website is no longer online.

Sonos has not released any announcement to confirm the acquisition, leading the technology website Protocol to publish a story that speculated on its motivations for the acquisition, including Sonos’ intention to release its first headphones - which is something that makes complete sense. What didn't make sense was the speculation that this article triggered in other "click-bait" tech websites, about Sonos using Wi-Fi instead of Bluetooth for its headphones.

Although Sonos has been focused on Wi-Fi applications for its foundational home audio products, in early 2021 the company released its first Bluetooth-centric product, the ultra-portable Sonos Roam speaker ($169). The new design can be fully connected to a Sonos system on Wi-Fi at home, and automatically switch to Bluetooth when the user is on the go. This effectively makes the Sonos Roam a very different product that is effectively an extension of the company's ecosystem, combining a simultaneous connection to both Wi-Fi (802.11b/g/n/ac 2.4 or 5 GHz) and Bluetooth 5. It even features Sonos' automatic Trueplay tuning technology with spatial awareness to adjust the sound for the speaker's orientation, location, and type of content - both with Wi-Fi or Bluetooth sources.

The challenges of designing low power, battery-operated products that are connected to Wi-Fi are well documented and are the reason why Bluetooth dominated mobile applications first, and gradually invaded the home space as well - as Apple painfully learned in its now discontinued HomePod. Today, all TVs launched in the market have to support Bluetooth as well, because consumers expect to be able to connect their headphones and earbuds and without the need to purchase complicated adapters.

The consensus, until recently, was that Wi-Fi would remain the preferred data and device network technology wherever there was a power source available, and that Bluetooth would be mainly adopted for battery-powered and low-power mobile applications. On the other hand, music enthusiasts, and anyone who actually cares about high-resolution, uncompressed, or lossless audio, remain limited in their choices of portable equipment, or restricted to home connectivity. And now, the requirements are getting even more complex with the introduction of spatial audio, already supported by music streaming services.

As I have been discussing with current efforts for products implementing Matter, the new smart home interoperability standard, companies such as NXP, Infineon, and Synaptics have all announced chips with combined support for Wi-Fi 6/6E, Bluetooth 5.2 with BLE Audio, and IEEE 802.15.4 for the Thread protocol and Matter application layer. Indirectly, those solutions will enable product development of hybrid connected products that will work inside and outside the home, adjusting to multiple wireless audio technologies, profiles and codecs. We already had Wi-Fi/BLE solutions in the form of relativity large boards and modules from Frontier Smart, Linkplay, StreamUnlimited, or Libre Wireless, but now we will have triple-connectivity miniaturized platforms that could seat comfortably inside portable speakers and headphones.

That might be very well the foundation for Sonos to release “hybrid” headphones. And, as I noted in my previous article, Sonos (and Ikea) are the only audio-centric company participating in the Connectivity Standards Alliance, among the 220-plus active members participating in the Matter specification effort.

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