When the first Sonos Arc debuted at the start of the pandemic it was the right product at the right time: a high-end soundbar with multiroom capability that felt worth the splurge. No one was visiting cinemas, everyone was trapped at home, so movies started coming out on TV instead. To meet the sudden need, the Arc soundbar provided a decent approximation of cinema sound in a compact, stylish package.

The updated Arc Ultra reviewed here takes the first Arc and tweaks it in a number of ways. For instance, it now comes with dedicated bass drivers and calibration for Android and iOS. According to my listening tests the sound is quite different as well. It's more contained, yet also more refined, and definitely sounds better for music. There is also a $100 price increase on top of the already hefty price.

However, the original Arc is still available and discounted until it sells out, creating a $400 gulf. If you're a cinema fan, get the original. It sounds more fun for movies and it's relatively affordable compared to the Ultra. The new model sounds great too, in particular for music, but isn't quite as room-filling as the current Arc or the competing Bose Smart Ultra Soundbar I tested.

What's in a name? Sonos Arc vs. Arc Ultra design, features

When companies name their step up products there is only a small pool they can draw from: Ultra, XL or Pro -- that's all there is. They can't have more. As an "Ultra," one might naturally assume this model is a higher-end version of the existing Arc. No, instead this new soundbar replaces it and Bose pulled a similar trick by substituting the Smart Soundbar 900 for the Smart Soundbar Ultra.

Sonos' upgraded version of the Arc includes a number of new features including onboard "subwoofers" and automatic room calibration. As you'd expect for a single soundbar at the $1,000 mark, this model offers Dolby Atmos compatibility and music streaming as well. The Arc Ultra is part of Sonos' multiroom system so it can be supplemented with a subwoofer and surrounds or play music in sync with other speakers in your house.

The price bump isn't too bad either -- an extra $100 which goes toward the speaker's new Sound Motion technology. This enables the speaker to "obtain a deeper, more powerful bass response in a smaller package," freeing space for additional tweeter and midrange drivers.

Looking at the two Arc soundbars side by side, you can tell how they have changed the Arc, especially at the back. The rear of the Arc Ultra now has a clip-on-like attachment at the back that houses the controls as well. The measurements are largely the same, though, at 2.95 inches high, 46.38 inches wide and 4.35 inches deep. While the soundbar is designed to sit beneath the TV on a console, the company does make a separate wall mount for $79.

While the Sonos Arc Ultra claims to be a 9.1.4 soundbar this may be taking creative license with Dolby's nomenclature. What it really means is that this is a soundbar with 16 (9+1+4) drivers, and not the five or so surrounds it suggests (it's a single speaker, after all). The soundbar does have seven angled silk-dome tweeters in tow, with two upward firing for Dolby Atmos height effects. Interestingly, the soundbar won't decode the rival to Dolby Atmos -- DTS-X -- though this isn't as important as most streaming uses Atmos, anyway. Home cinema enthusiasts will already be looking elsewhere.

One of the features to come out of the launch of the Sonos Ace is Sonos TV Audio Swap, which lets users toggle sound between the headphones and the soundbar. This feature is also available on other S2 series soundbars including both Beams, Ray and original Arc.

Sonos has had onboard virtual assistants since the time of the first Amazon Echo, and while the Arc Ultra has one too, this is not the must-have feature it once was. There are two issues here -- first, smart speakers are cheap and easier to replace, and second, it's now Alexa only, as new Sonos speakers haven't been able to do Google Assistant since the release of the Era range. The speakers will do Sonos Voice Control for control of the device itself.

Those voice assistant microphones do another purpose, as the Arc Ultra gains the quick-tuning Trueplay of the Era 100 and Era 300. This means now Android and iOS users can tailor the speaker to their space. I used an iOS device to do the full tuning in CNET's testing studio.

The Sonos Arc UItra lacks a remote control -- instead relying on HDMI CEC so you can use your TV remote. For all else, the app enables you to toggle sources, line up music and choose from among the dizzying array of streaming services. While Sonos did have a turbulent year with customers experiencing ongoing issues with the app, I can say I haven't seen any issues of late and I am a regular home user of the Beam.

Performance and listening tests

I tested the Sonos Arc Ultra against the original Arc as well as the other competitive soundbar at the price -- the Bose Smart Ultra Soundbar -- using a mix of movies and music.

In my testing, I didn't hear the "more expansive soundstage" the marketing promised when comparing the Arc directly against Arc Ultra. In fact I heard the opposite. Instead of the huge, room-filling sound of the original Arc, the Arc Ultra delivered specific placement of audio elements. That is, the sound was more closely mapped to the screen and contained within the dimensions of the bar itself. Which is better? The Ultra was more refined than the Arc with music but is that necessarily what people buying a high-end soundbar are looking for?

I began my testing with some lossless music streaming from Tidal, and as I was in the mood for some math rock I cued up Right the Relation from Polvo's comeback record In Prism. The track curls and winds around a chugging guitar and it sounded fuller on Sonos Arc Ultra than Arc. The song sounded a little slight on the Arc, and while the Ultra sounded like a stereo system the Arc sounded like what it was -- a soundbar.

I continued with Bill Ryder-Jones' choir-led anthem We Don't Need Them and found the Ultra was again more present-sounding than the Arc, with a better grip on dynamics and heftier bass, even though it lacks the chunky riffing of the former song. It's a gentler song but still benefitted from enhanced bass.

I switched to some movies and the new Sound Motion system made its presence felt here in a different way. Do you like explosions? The Arc Ultra has got your back. In the opening scene of Mad Max: Fury Road the Arc relayed the disembodied voices with plenty of air and sparkle and the sound encompassed the whole room. Meanwhile, the Ultra had more bass and the thunk of the car door at 1.02 was more felt than heard but the effects weren't as room-sized.

The Ultra kept the sound closer to the screen, as I found with the film Avatar, but was also more thoughtful about where it put effects. The original Arc sprayed them all around the room. The Ultra threw effects when it demanded them, like the titanothere disappearing off to the right hand of the screen. It followed the action better. But overall the original Arc sounded more fun.

Next I switched to a comparison between the Bose Smart Ultra and the Arc Ultra using Mad Max. The Bose sounded big in the same way as the original Arc. The opening voices of the film were spaced around the room and achieved decent height levels. While the Arc Ultra was more contained its bass did make the Bose sound a little slight in comparison. The Arc Ultra had better bass definition and impact, and lent more weight to Tom Hardy's voice.

Next, I wanted to hear the benefits of using Arc Ultra as a base for a surround system, with a pair of Era 300s and the new Sub 4. Although this combo more than doubled the price, the improvement in surround was obvious. Voices came from around the seating area, in this Mad Max scene, and explosions had even more depth. If you want to build upon the Arc Ultra's sound, then surrounds are a great first upgrade -- you could even use the less-expensive Ikea Symfonisk.

While I didn't compare the Arc directly to less-expensive Sonos soundbars like the the Beam or the Ray, I can tell you from experience that neither of those models are particularly great with music. And both of them could use the help of a separate subwoofer -- something the Arc Ultra doesn't require. So in both regards, the Arc Ultra should be your choice if you want improved bass or if music is your main concern.

Should you buy it?

When the original Arc came out it, it was an impressive speaker with a surprising amount of bass. Yet, the Ultra is even better in that regard, and can shame the bass of the Bose Smart Ultra Soundbar, too. In terms of the differences between the Arcs in sound quality, for $400 less, the Arc is cheaper and more enjoyable with movies. This may change but it's unlikely to be drastic given the Ultra soundbar has been out for about six months already.

Functionally, the two units are the same, so it's worth going the affordable route. That said, the Ultra is much more suited for listening to music, so if that is more important to you, then the Arc Ultra is the best-sounding Sonos soundbar for music fans.