SONOS ARC SOUNDBAR
THE NEW Sonos Arc soundbar is the company’s fourth home theater product and the clear result of an evolution. The first Sonos soundbar, the Playbar ($599 and currently being closed out), debuted back in 2013. But with only a single optical input intended to ease installation and no HDMI port, it was already outdated on Day 1. In 2017, the company introduced the Playbase sound platform ($699, also being phased out), a solution for those who found the bulky Playbar too invasive. Playbase was extraordinary for its ability to extract bass from its lean cabinet, but still failed to take advantage of a higher-quality HDMI connection or the benefits of HDMI- CEC control. The Sonos Beam ($399), a more compact and affordable soundbar (or “living room speaker” as Sonos likes to call it), came out about a year later and today is one of the company’s most popular products. Not only did it finally integrate HDMI-ARC connectivity, but it also added Alexa voice control of the bar and connected devices. From an audio engineering perspective, it drew heavily on what Sonos had learned creating the small, highe-xcursion elliptical woofers and low-resonance cabinetry for the Playbase.
The Arc ($799) is a culmination of all that development, and with a 45-inch width, is almost 10 inches wider than the Playbar to better mate with today’s larger 55- and 65-inch TVS. But that extra width
is also there to accommodate more drivers that, along with some sophisticated processing, are used to deliver immersive effects from Dolby Atmos soundtracks. Though home theater enthusiasts have long embraced Atmos playback and its additional overhead information from Ultra HD and regular Blu-ray discs, Sonos says that more than 25 streaming services now pass along Atmos programming. Some six years after its introduction to home theater, Atmos has officially gone mainstream.
FEATURES
As usual with Sonos, the industrial design of the Arc is understated, classy, and in service to the sonics. The soundbar is available in matte black or white. Viewed from the side, it is a near perfect ellipse; the only disturbance to the visual flow is a subtle bracket that serves as a base for resting it flat or attaching it to its optional $79 wall-mount. The front surface is wrapped by a 270-degree curved grille made from a single sheet of thermoformed plastic into which are drilled 76,000 holes. Capacitive touch controls similar to those on the Beam and other current Sonos speakers are on top and allow for volume up/down, play/pause, and skip/repeat. A group of tiny LEDS indicates speaker status and the built-in multi-microphone array used for Alexa and Google Assistant control. An ambient light sensor gracefully dims these in a dark room so they won’t be a distraction, and they can also be turned off in the Sonos app.
There’s some clever engineering behind how the Arc’s 11 speaker drivers work together. Each driver operates independently from its own class-d amplifier of unspecified power, with its signal phase and amplitude optimized in real-time to allow the bar’s speaker arrays to steer sound in specific directions. There are eight 2x3-inch aluminum elliptical cone woofers, with four on the front baffle along with three 0.75-inch silk-dome tweeters. The left and right tweeters are paired with woofers and have waveguides that fire them out at 60 degrees toward the side walls. A pair of woofers and a tweeter are also mounted at the bar’s center, and there is yet another pair of woofers firing straight out at 90 degrees from the bar’s ends. The final two woofers, also in wave guides, fire at the ceiling with a modest tilt toward the listeners.
Audiophiles looking at a graphic of what’s behind the grille will be curious why the center array, with its two woofers and tweeter, has a woofer in the bullseye position rather than the tweeter. The short answer is that it is the distance between the woofers here that determines the pair’s upper frequency limit—which needed to be as high as possible to ensure its sonic match with the side-firing arrays on the far edges of the baffle and the ends of the bar. As a Sonos engineer explained it, “The best sound experience resulted in a swap of the center tweeter with a woofer to position the center woofers as close together as possible, with the woofers being twice as close as they would have been if the tweeter was in the center. The net effect was that the array’s upper limits were extended a full octave higher. This helped us get a smooth transition from the arrays to the high-frequency components and a smoother power response overall.”
In what is again a repeat of earlier Sonos soundbars, the rear connection panel of the Arc is nearly a void. There’s a single HDMI EARC input (with backward compatibility to regular ARC displays), an RJ45 Ethernet port in the event the onboard 802.11b/g 2.4 GHZ Wi-fi proves unreliable, a power-cord socket, and a reset button. Sonos provides an Hdmi-to-optical adapter for older TVS without ARC. System control is provided by the ARC connection in conjunction with HDMI-CEC, which lets the TV handset or a universal remote control volume, but the bar has an IR receiver and can be trained to respond directly to a TV or set-top box remote if you’re using the optical adapter. Alexa and Google Assistant voice commands can be used to control volume or call up music and advance tracks from compatible services. If you end up connecting an Amazon Firestick or Google Chromecast streaming dongle to your TV, you gain the ability to search and call up video content as well. Furthermore, the Arc is compatible with Airplay 2, so it can be tapped from your iphone’s speaker menu and music, podcast, or audiobook apps.
Of course, the Sonos app also provides control and a range of adjustments. Concurrent with the release of Arc, Sonos rolled out its new S2 version. It’s required for Arc but also makes ergonomic tweaks said to improve the user experience. If you’re familiar with the most recent Sonos app you won’t have much to adjust to.
As with previous Sonos soundbars, owners have the option of adding a subwoofer and rear surrounds to the system. Also simultaneous with the launch of the Arc, Sonos announced its 3rd generation Sub subwooofer ($699), with updated internals that include more processing power and memory to better drive the
Sub’s pair of opposing, force-canceling drivers. From its initial launch in 2012, the Sub has remained a remarkable overachiever dressed in exceptional industrial design. I used my first-gen Sub for this review with excellent results and felt that the Arc really needed it to perform at its best— more on that shortly. A pair of Sonos One SL speakers ($179 each), the most recent generation of the original Play:1 “not-smart” bookshelf speaker, is the recommended add-on for the rears. I tried the Arc with a pair of Play:1s, which are a close sonic match. As described below, they were even more essential than the Sub to get the most out of Arc.
SETUP
Depending on your perspective, the Arc’s single ARC HDMI input, with no internal switching or HDMI output for passthrough, is either a blessing or a curse. Sonos has gone the one-input route from the beginning, even in the optical-only Playbar and Playbase, on the thought that ease-of-use demands a single instant-on connection
to the TV audio output and that users will always use the TV input selector for switching among sources. The times have perhaps caught up with that thinking, as so many viewers watch today from their TV’S built-in streaming apps rather than a separate media or disc player, and therefore require a straight audio connection from the TV to access that sound.
Nonetheless, this approach chews up what is usually the one HDMI ARC or EARC connection on your display, leaving you short at least one video source input. Depending on the display and its number of HDMI or Ultra Hd-compliant HDCP2.2 inputs, this can present challenges. The LG HU85LA ultra-short-throw projection TV I initially used for my review, despite being introduced just last year, has only two HDMI inputs, one with ARC, which left me with only one external source connection.
Furthermore, the LG’S port is ARC and not the newer EARC. In theory, ARC allows passage of Dolby Atmos soundtracks coming into the TV from a source component or its own onboard streaming platform, just married to a lossy Dolby Digital Plus base rather than the lossless Dolby True HD associated with Atmos coming off a Blu-ray Disc. However, this is also dependent on the TV’S capabilities— what the streaming service sends based on what it sees at the receiving end. The Sonos app helpfully flags you when it recognizes an Atmos soundtrack, but the LG projector, despite being a Ultra HD display with LG’S up-todate WEBOS 4K streaming platform, would not pass Atmos to the Arc whether I streamed known Atmos programs from WEBOS, a connected Roku Ultra or Chromecast Ultra 4K streaming player, or a Blu-ray player. Nor does the Arc allow a direct HDMI input from a player or any source; its port is strictly an EARC audio connection.
Eventually, I connected the soundbar to a new LG OLED TV with an HDMI EARC port. This let me play Netflix and Amazon Prime Atmos programs with a Dolby Digital Plus base from the set’s streaming platform or the connected media players, as well as play Dolby True Hd-based Atmos soundtracks from my disc players.
Those issues aside, setting up the Arc was a breeze. You simply boot up the Sonos app, connect it to Wi-fi, plug in the bar, hit a button on the back to let the app know it’s there, and the app does all the rest of the work. It tells you when to plug in the HDMI cable coming from your powered-up TV and automatically negotiates the connection. If your setup requires the optical adapter, you’ll teach the Arc to respond to your TV remote.
Once that’s all done, the app steps you through joining it to your Alexa or Google Home account, and you then sign into your favorite streaming music accounts so Sonos can access them. The last step is to run the Sonos Trueplay routine to adapt the Arc to your room boundaries—a critical step given the Arc’s reliance on the walls and ceiling to reflect sound.
For my auditions, I placed Arc about a foot below at my sitting ear-level to ensure optimal sound quality. I played 5.1-channel Dolby and Atmos soundtracks as well as DTS from my streaming devices and discs. Note that since there is no onboard DTS decoder, multichannel DTS soundtracks must be sent by your source in two-channel PCM format. (Sonos has never put discrete DTS decoding in its soundbars, presumably because Dolby is universal to all sources and only a minority of users will use Blu-ray discs for playback.) To assess the Arc’s music chops, I listened to Cd-quality streams from Tidal and some CDS via my disc player. I listened first to the bar alone, then with the surrounds, then added the Sub to assess the improvements as I went along.
PERFORMANCE
Whether I served the Arc simple stereo music, multichannel Dolby Digital, or Dolby Atmos, I found it to be an impressive and capable performer either alone or with its companion surrounds and subwoofer. The sound of the bar by itself can be characterized as exceptionally smooth and unveiled in the midrange right on up through the highs— I was pleased to hear clarity in the upper registers with none of the supressed detail that sometimes accompanies cloth-dome tweeters. And yet, the Arc’s cloth-dome friendliness kept bright soundtracks palatable and unfatiguing even at a loud volume.
At the other end of the frequency range, test tone sweeps suggested an extremely even transition from the midrange down to the bar’s lower limit. With the app’s bass tone control set to its 0 default and the default Loudness compensation turned off, the bar added a tiny blip of extra energy somewhere in the 100 to 250 Hz range, but hardly enough to sound bloated or over-enhanced. Goosing the bass slider gave it a touch more fullness, but I didn’t overdo it. In my fairly large studio space, the usable bass stayed remarkably present and consistent right down to about 60 Hz, where it abruptly fell off. You might do better if the bar is placed nearer to room boundaries than I’m able to do in my setup, but let’s be clear: 60 Hz is pretty damn good for a standalone soundbar. It was enough to make the Arc a serious rig for most music and typical TV viewing, though not quite enough to deliver a fully balanced and impactful home theater experience with movies. This doesn’t mean it was a letdown with action flicks, only that it was ultimately limited in what it could do with bassheavy effects.
With all of its drivers working, the bar created a beautifully broad image with stereo music tracks, one that went almost wall-to-wall in my 11-foot wide viewing area and easily reached up to the relatively low ceiling in the finished basement of my 90-year-old home. Centered vocalists and soloists projected well forward of the bar, and from my 10-foot listening distance the system hit 92 db peaks with no obvious distortion.
The Arc’s easy and unfettered mids and highs were apparent on a jazzy rendering of “I Remember You” by the Elmo Hope Trio. Hope’s piano notes floated out in the room with palpable body and natural timbre, while the brushed snare accompaniment retained its fine, papery detail and the standup bass provided a sufficiently full and tuneful undercurrent. Tracks recorded with an audience, such as Luther Vandross doing “A House Is Not A Home” on Live At Radio City Music Hall 2003, rendered a nice one-third dome of applause that imparted a sense of ambience but couldn’t
reach far enough to put you in the hall. Still, it was a spacious and engaging effect.
More dynamic, wellrecorded pop tracks such as “What I Can Do for You” from Sheryl Crow’s classic Tuesday Night Music Club album proved the Arc capable of letting its hair down. Vocals were portrayed as big and solid, and the bar did a respectable job with the song’s driving kick drum, though its low-end limits made it a less visceral experience than I’m used to hearing from my sub-supported reference system.
Movie soundtracks enjoyed the same benefits of the Arc’s well-balanced and open sonics, as well as the same drawbacks of limited bass and restricted depth that can be attributed to any up-front soundbar operating without dedicated rear surrounds. Playing discrete Dolby Digital 5.1 and Dolby Atmos 5.1.2 pink noise tones from test discs was instructive in showing what Sonos engineered the bar to do with multichannel signals. No matter what channel was sent to the bar, all the drivers were actively working, but the noise always emanated from a fixed location. The main left and right channels were stationed beyond the left and right endcaps after taking advantage of room reflections, and the center channel was locked solidly to the middle. The left/right rear surround information came from essentially the same locations as the main left/ right channels at the front of the room but sounded a touch more spacious. On the other hand, the front height information present in a 5.1.2 Atmos signal was impressively anchored on the ceiling about a third of the way back toward my seating area...precisely where it should be. (The rear height information in a 5.1.4 test signal fell in precisely the same location.)
AND THEN THERE WAS SUB
Given the placements of the virtual speakers, it was no surprise that the bar by itself playing regular 5.1 Dolby
Digital soundtracks exhibited a wide and tall soundstage with reasonable depth and some wrapping of sound on the side walls, but none of the rear fill you’d normally get with surrounds. And while the bottom end was serviceable and perhaps enough for many viewers, it wasn’t nearly enough in my room to balance out the Arc’s excellent and dynamic playback above that 60 Hz mark. Adding the Play:1 speaker pair as surrounds made an enormous difference, both by expanding the soundfield fully to the back of the room and allowing greater delineation of instruments and sound objects in a manner that seemed to strengthen the bass presence even without adding the Sub. When I finally did so, it took the system to yet another level.
The early attack and crash scene in the Blu-ray of Star Trek Beyond that sees the Enterprise boarded by Krall’s soldiers and eventually destroyed has an expansive mix of surround effects. Even in Dolby Digital
5.1 with no surrounds or subwoofer, this was an impressive sequence on which the
Arc delivered a solid wall of sound up front that offered all manner of creaking metal, traveling phaser fire, explosions, and other mayhem set against dialogue that was clear enough that I never needed to invoke the Sonos app’s speech enhancement mode. But the rear effects never reached terribly far back to create a sense of envelopment. Switching to the disc’s Atmos track, which added the wellplaced virtual height speakers and its discrete effects, noticeably expanded the surround bubble forward but still left it well short of the back of the room. The sound also benefited from a welcome jump in dynamics and openness as a consequence of moving to lossless Truehd.
Switching in the surrounds with either the 5.1 or Atmos tracks added a tremendous sense of dimensionality and a continuous bubble that allowed effects like a fragment swarm that engulfs the ship to pan from front to back. With the Atmos version, however, a full dome of sound was generated and those fragments were able to pass right through the viewer. Music was also greatly transformed with the addition of the surrounds. The app’s Ambient surround option for music always seemed to steer just the right elements in just the right amounts to the rears; on the Luther Vandross track mentioned earlier it put me literally in the middle of the audience with applause coming from behind and in front. Once the surrounds were present, Atmos music tracks were also a home run: watching a video for the techno track “Swivel” by London Elektricity amounted to a near-hypnotic experience.
It should go without saying that adding the Sub addressed any lack of bass with either music or movies and allowed the bar to play louder and cleaner. With the subwoofer installed, the test tones revealed usable and very taut bass down to about 35 Hz, and the Arc took firm command not only of any and all action effects such as the rumbling of an approaching squadron of WWI bomber and fighter planes in Unbroken, but demanding music as well. The R&B track “Still” by Donnell Jones from Life Goes On has some stupendously low bass. The song sounded reasonably full and impactful on the bar alone, but adding the sub took it right into chest-compression territory. Now, that’s what I’m talkin’ about.
CONCLUSION
Most folks would say $799 is a lot for a soundbar, especially one that doesn’t ship with a subwoofer or surrounds. But the Sonos Arc is a brilliantly engineered and worthy successor to the Playbar that sounds amazing with movies and TV, and, critically for Sound & Vision readers, delivers a truly respectable audiophile experience with music. The excellent Sonos multiroom music streaming platform on which the company was built here becomes the icing on the cake.
As with any soundbar that relies on room boundaries, the Arc’s bass extension and its success at rendering surround sound will be dependent on your space. The Sub subwoofer is a recommended option.
And given how effectively the Arc projected Atmos height information, I’d strongly suggest popping for rear speakers to complete the effect and experience Atmos as it’s truly meant to be heard. Oh, I’m betting you’ll love Arc even without the surrounds. But they are a transformative add and successfully drive home what Sonos has accomplished here in a fairly svelte soundbar—a very near equivalent to a discrete Dolby Atmos system, and one heck of a fun ride.