The new Sonos Arc Ultra soundbar is here, and it’s coming in hot with some pretty bold claims. 9.1.4 Dolby Atmos like never before? Best in class vocal clarity? Up to double the bass compared to the original Sonos Arc? New Sound Motion technology, which is one of the biggest breakthroughs in audio in the last 100 years? These aren’t claims you can make without having some serious confidence in this new soundbar. In this article, we’re going to not only go over all the new features and technology in the Arc Ultra and new Sub 4 subwoofer, but we will also put them to the test to see how they stack up to the competition.

The first Sonos Arc came on the scene in 2020 and really took the soundbar world by storm. In fact, we’ve continually stacked it up against the best soundbars each year, and time and time again, it makes our list of the top Dolby Atmos soundbars.

At first glance, the new Arc Ultra doesn’t look much different from the original Arc—you still get that signature curved shape and low-profile design. But when you look closer, you’ll notice the Ultra is actually a bit smaller overall. It’s almost half an inch shorter, which makes it easier to slide under a TV on a credenza, and it’s about a pound lighter, too. The main new feature is the thin control panel on the back, where you’ll find a voice control touch button, playback controls, and a volume slider.

But the real upgrades live inside this soundbar. The first one we want to discuss is the groundbreaking innovation called Sound Motion. Sonos quotes this as a significant breakthrough in audio engineering that drastically reduces the size of the transducer while supercharging the bass, and it’s the first time they’ve used it in any of their products. However, this technology isn’t exactly brand new. Sonos acquired a company called Mayht a few years back that developed a version of this that was set to enable smaller and lighter form factors of transducers to have more output without compromising on quality.

The Arc Ultra, with its Sound Motion woofer, is a powerhouse designed for a 9.1.4 Dolby Atmos experience, featuring a completely revamped acoustic architecture. It now boasts 14 drivers, up from the original Arc’s 11. These include seven silk-dome tweeters for clear highs, six woofers for midrange, and the Sound Motion woofer handling the bass. Each driver is carefully positioned to enhance dialogue clarity and expand the soundstage. Side-firing drivers project sound from wall to wall, while upward-firing drivers bounce audio off the ceiling, delivering an immersive spatial experience. They've also optimized the design with custom colinear waveguides to evenly spread sound throughout the room for a balanced, dynamic audio performance.

If you've ever watched a movie and struggled to hear what the actors were saying, you know how frustrating that can be. Most soundbars help with this, and that's one of the reasons we loved the Arc—it made dialogue crystal clear, even in loud, action-packed scenes. With the Ultra, they've taken it up a notch, improving vocal clarity even more. Plus, they’ve added a new Speech Enhancement feature that you can adjust directly in the Sonos app, so you can customize it to make every word stand out exactly how you like.

Trueplay room correction is still available on the Arc Ultra, but now, finally, it’s available for Android users, too, not just iPhone users. However, it is a bit different from an Android, as it will use a feature called QuickTune, which uses its onboard microphones to calibrate itself, instead of the phone’s microphones as it will do with an iPhone. It’s nice to see that Android users are invited to the party here, but you will still get a more full and advanced experience when using an iPhone, so we’d recommend that route if possible.

You can still connect using the Sonos app over WiFi for the best sound quality, or go with AirPlay 2, Spotify Connect, and now they've added Bluetooth 5.3, just like their latest products. Plus, you can control it with Sonos Voice Control or Alexa with simple voice commands. However, Google Assistant has been removed. There’s also a handy switch on the back to turn off the microphone if you want more privacy.

Besides the mic switch on the back, you’ve got your single HDMI eARC port, a Bluetooth pairing button, and an Ethernet port for a more stable connection, which we always recommend if you can use it. If your TV supports it, definitely go for the HDMI eARC connection; it gives you the best sound quality and lets you control the volume with your TV remote. However, you can purchase a separate Optical Adapter if you need to use an optical cable for your TV. It would’ve been awesome to see a few more HDMI ports for those of us with gaming consoles and other devices, but Sonos has opted for a minimalist I/O section with the Arc Ultra.

The last cool feature we want to highlight is the ability to send your TV audio from the Arc Ultra straight to your Sonos Ace headphones with just a press of a button. When you do this, you get some awesome dynamic head-tracking that adjusts the sound based on which way you're facing, keeping you right in the middle of the action. When we tested it, we loved how quick and easy it was to get sound to our headphones. The head tracking is a fun touch that really amps up the immersive experience, but you do need to have the Sonos Ace headphones to use this feature.

As we mentioned earlier, the new Sub 4 is being released alongside the Arc Ultra and features a few upgrades from the Sub Gen 3. It’s still the same shape with the dual force canceling woofers but now comes in a sleek matte black or white finish. Inside, there is a new wireless radio that enables stronger connections to your other Sonos speakers, and it has increased memory and processing power to support future innovations. While the Arc Ultra will have more bass than the Arc, it still can’t reach as low as the sub, which can go down to around 25 Hz. Adding this sub will give you the low-end punch that really hits you right in the chest.

All these upgrades sound great on paper, but what everyone—including us—really wants to know is how the Arc Ultra stacks up against the original Arc and other soundbars in this price range. Does it really deliver double the bass? Are the dialogue and vocals clearer? Do you still need to add a subwoofer? Luckily, we got our hands on the new Arc Ultra and Sub 4 early to find out. We tested the Arc Ultra on its own, paired with the Sub 4, and in a full home theater setup with Era 300s as rear speakers in one of our home theater labs. Then, we compared it side by side with the original Arc and a few competitors and what we found was pretty interesting.

The first one we tried was “A Concert Six Months From Now” by FINNEAS. This track starts with some beautiful, delicate acoustic guitar that fills the entire soundstage. FINNEAS’s vocals filled up the lower mid’s with a warm, rich, and full sound. What really stood out to us was the subtle harmonies in the background of his voice that came to life, and each voice and instrument had its own spot in the mix. At about 1:45, the drums and other instruments picked up in the song, and the bass, even without a sub, had incredible depth and speed. Compared to the original Arc, the Arc Ultra sounded much closer to a true 2-channel setup with separate speakers. The vocals floated in the middle, and the instruments were spread out with a sense of spaciousness throughout the entire soundstage. The extra bass from the Sound Motion tech was able to handle the low end of the mix so better with more detail and punch, which also really took the load off the other drivers to allow the vocals to really shine and stand out. Just after listening to this one song, even without attaching the Sub, we were extremely impressed with the Arc Ultra. It absolutely was much better than our expectations, especially because we think the original Arc is already a pretty fantastic soundbar. But boy, Sonos has seemed to really figure something out with this new Arc Ultra.

Just to confirm our first impressions, we listened to different songs like “Von dutch” by Charli xcx, “Go Home” by Lucius, and “I’m Coming Out” by Diana Ross. With each new track we tried, we were continually impressed with the low end in the Arc Ultra. Was it double the amount of bass output? We believe in a controlled test setting, and yes, it can probably reach double the output. But in a real-world testing scenario with different music, it was very, very close to double and is certainly enough to notice it when comparing side by side with the original Arc. And when it came to using these songs in Dolby Atmos, we felt there was definitely a better sense of precision and detail with where it placed certain instruments in the mix. Of course, when we added the rear surrounds, the Atmos songs sounded even better. However, if you have a smaller room with hard, flat ceilings and nothing in the way, you can get a pretty fun 3D bubble of sound with just the soundbar itself.

Moving to movies, we tried out a few different clips from movies like NOPE, Our Planet II, Stranger Things 4, and Jurassic World: Dominion. Let us cut to the chase here. The Arc Ultra sounded better in just about every way than the original Arc. But what really stood out here was the clarity of the dialogue in the movies. Even when we played a few clips from movies that had some poor and quiet dialogue in the mix, turning on the Speech Enhancement seemed to really fix it to make it a more enjoyable experience. It’s a little hard to describe, but it doesn’t exactly make the character's voices louder while drowning out the rest of the mix; instead, it just makes it so much clearer. When adding one or two Sub 4s, you will get that deep, powerful bass that hits you right in the chest when there is a big explosion or earth-shattering roar in the film. And adding the Era 300s gives you that immersive bubble of Dolby Atmos sound. In fact, we found that sometimes the Era 300s were almost overkill with the original Arc, but with the new Arc Ultra, they seem to fit right in to give you an extremely balanced and powerful movie-watching experience.

So, what would we recommend here? Well, if you have a smaller room, the new Arc Ultra will give you incredible sound, and you may not even need a sub or surrounds to start off with. We found the original Arc to be one of the best soundbars on the market when it came to Dolby Atmos effects, and the Arc Ultra is even better. To our ears, it beats all of the competition on the market right now for Dolby Atmos sound effects when it comes to soundbars with no extra rear speakers. We’d probably also place it in the top 3 when it comes to dialogue and vocal clarity, competing with soundbars like the Devialet Dione and Sennheiser Ambeo, which are twice the price. So, if you own the original Arc and have wished for a bit more bass and better dialogue clarity, you have our permission to upgrade to the Arc Ultra.

If you have a medium to large room, like a living room or media room, you’d still benefit from upgrading from the original Arc, too. Adding a subwoofer will be what takes the performance of the Arc Ultra over the top, but if you have the Gen 3, it will be less crucial for you to upgrade to the Sub 4. We found from our listening tests that the increase in performance was only incremental, so we don’t feel the need to recommend that you upgrade unless you just want the absolute best that Sonos has to offer. And while the Arc Ultra certainly starts to make you wonder if you even need a subwoofer since it has more bass output, we’d really recommend adding one if you plan to watch movies because it can just reach much lower and hit you right in the chest during those loud action scenes. In fact, even when playing music, we found it to really even out the entire mix for a much more enjoyable and balanced experience. So, while the Arc Ultra definitely can stand on its own much better than the original Arc, adding a sub would be our first recommendation for better performance, even before adding surround speakers.

Now, when we finally paired up the Arc Ultra with the Sub 4 and two Era 300s as surrounds, the experience was top-notch for a wireless surround sound system with a soundbar. While a setup like this isn’t cheap at around $2,500, it’s still more affordable than something like the Sony Bravia Quad system with a subwoofer and arguably sounds a little bit better. Of course, you can get very close to this setup and sound with something like the JBL Bar 1300X or the latest Samsung or Sony flagship setup for a little less money, but if you want to have the ultimate experience, go with the Sonos system that we described, and you will be happy.

Now, we know that soundbars have a certain place in the market. They are much smaller than box speakers, have easy setup without running wires all over, and you can usually place one below your TV and be ready to go. However, when you start getting into the price point of the Arc Ultra and begin adding on more speakers and accessories, we can’t help but mention that there are other alternatives that will give you better sound close to this price range but come at the cost of convenience. The speakers will take up more space, and you’ll need to plan to run wires around your room to them, but if you are interested in a setup like that and don’t know where to start, reach out to our experts at audioadive.com and we can help you determine if going that route is better for you in the long run.

Hopefully, you’ve got a good understanding of what Sonos has to offer with the new Arc Ultra and Sub 4, and we’ve given you some insights into whether you should upgrade your system or not.

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