Sonos' Arc Ultra soundbar is official, with revolutionary new speaker tech that offers 'double the bass'

Sonos Arc Ultra in white with a woman's hand pressing the control
(Image credit: Sonos)

The Sonos Arc Ultra is official, and it's launching on October 29, 2024, at a price of $999 / £999 (Australian pricing is yet to be confirmed). It's a massive upgrade over the existing Sonos Arc, and introduces a brand-new speaker technology that promises to deliver incredible immersion which looks set to rival the best soundbars.

Here's what you need to know…

Sonos Arc Ultra: key features and specifications

The original Sonos Arc was a 5.1.2 surround system, but the Arc Ultra is 9.1.4. And it has what Sonos calls Sound Motion, the technology it acquired when it bought speaker firm Mayht a few years ago. The technology, previously known as HeartMotion, enables speakers to be made much smaller than those with traditional speaker drivers without compromising on power or sound quality.

Sonos says: "A significant breakthrough in audio engineering, Sound Motion drastically reduces the size of the transducer while supercharging the bass, opening a new chapter in sound innovation where bigger, better sound can be delivered from smaller products."

That means Sonos has been able to cram more bass power into what's still a relatively slim soundbar – in fact, Sonos says it's 18% smaller by volume than the original Arc. The Arc Ultra has dimensions of 2.95 x 46.38 x 4.35 inches (75 x 1178 x 110.6mm), and weighs 5.9kg. It comes in black and white finishes, as usual for the best Sonos speakers.

There are 14 drivers here, three more than in the Arc: seven silk-dome tweeters "with waveguides on both ends", six mid-range drivers, and a a built-in Sound Motion woofer.

Sonos adds that "a proprietary four-motor, dual-membrane woofer delivers exceptional bass in a revolutionary flat, compact design".

There are 15 channels of Class D amplification behind all of this – I presume two channels are going to the Sound Motion woofer, otherwise there's a spare.

Of note in the speaker configuration is that only two of the tweeters are upfiring, which raises questions about the 9.1.4 configuration – is Sonos just using processing to suggest more upfiring channels, or has it arrived at this figure some other way? I'll aim to find out.

As ever there's built-in support for wireless streaming services and easy integration with other Sonos devices. There's also a redesigned touch control panel, and the addition of Bluetooth to bring the Arc Ultra in line with Sonos's other products.

Sonos Arc Ultra: clever customization

The Sonos Arc Ultra can listen to the sound of your room and adjust its configuration accordingly thanks to the combination of integrated microphones and Sonos's Trueplay software, which is available for Android as well as for iOS for the first time, and there's also a more advanced Speech Enhancement tool that "lets you choose your preferred level of dialogue clarity in the Sonos app."

Sonos says the Arc Ultra is also designed for "improved serviceability" compared to the Sonos Arc, using "more screws and fewer adhesives, halogen-free PCB materials, less silicon material, and a reduced idle power consumption by as much as 20% as a standalone player compared to Arc."

The Arc Ultra is also designed to work with the new Sonos Sub 4 subwoofer ($799) for even more low-end power.

The Sub 4 has also been "rebuilt, inside and out", even though Sonos also says it has the "same iconic design". It includes "increased processing power and memory, as well as new Wi-Fi radios for better connectivity" and can be used in a pair with either another Sub 4, or with previous Sub models.

Sonos Arc Ultra: what we still need to know

I've approached Sonos for information about whether it will have only one HDMI eARC port, though I strongly suspect so based on the available information – this will be a huge disappointment if so.

I'm also waiting to hear whether any DTS decoding is supported (I doubt it) and whether the Sonos Ace headphones' switching feature is supported (I'm 99.99% certain it will be, but Sonos didn't explicitly say, though one of the press images shows them being used together).

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Carrie Marshall
Contributor

Writer, broadcaster, musician and kitchen gadget obsessive Carrie Marshall has been writing about tech since 1998, contributing sage advice and odd opinions to all kinds of magazines and websites as well as writing more than a dozen books. Her memoir, Carrie Kills A Man, is on sale now and her next book, about pop music, is out in 2025. She is the singer in Glaswegian rock band Unquiet Mind.

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