
Sonos Arc Ultra
Score: 85/100
KEF XIO
Score: 85/100Rankings

The Sonos Arc Ultra soundbar paired with the Sub 4 delivers a premium 9.1.4 Dolby Atmos experience with rich, detailed sound and deep bass, while integrating tightly with the Sonos ecosystem via Wi-Fi 6, Bluetooth 5.3, and eARC. Its sleek design and advanced calibration make it ideal for large-screen home theaters, though the lack of HDMI inputs and the heavy subwoofer are notable drawbacks.

The KEF XIO 5.1.2 soundbar delivers powerful, immersive Atmos sound with deep bass and high-resolution streaming, though it depends on a separate wireless subwoofer for extra low-end impact and requires app-based configuration.
| Attribute | ![]() | ![]() |
|---|---|---|
— | 820 Wbest | |
— | 34 Hzbest | |
— | 20,000 Hzbest | |
— | 1best | |
1best | 1best | |
5.3best | 5.3best | |
| ↓ lower better | 17.9 kg | 10.5 kgbest |
— | 24 monthsbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Build & Design(1) | ||
Overall Weight (kg) | 17.9 kg | 10.5 kg |
Audio(2) | ||
Channel Configuration | 9.1.4 | 5.1.2 |
Supported Audio Formats | Dolby Atmos, Dolby Digital, Dolby Digital Plus, Dolby TrueHD, Multichannel PCM, Stereo PCM, DTS Digital Surround | Dolby Atmos, DTS:X, MPEG-H, Sony 360 Reality Audio, FLAC, WAV, AIFF, ALAC, AAC, WMA, MP3, M4A, LPCM, Ogg Vorbis |


Products in the top-left offer the best value (high score, low price).

Professional reviewers praise the Arc Ultra for its clean, precise, three-dimensional soundstage, deep expressive bass, and effective Trueplay calibration, but criticize the lack of HDMI inputs and native DTS support, noting that height effects may be underwhelming without ideal room conditions.
Everyday users love the crystal-clear dialogue, powerful bass, and sleek look, while frustrations focus on missing HDMI inputs, occasional app freezes, subtle Atmos immersion, and the Sub 4's heft.

Professional reviewers from What Hi-Fi? and Crutchfield laud the XIO for its powerful, clean bass, precise imaging and ability to handle both movies and high-resolution music with equal finesse, calling it one of the best premium soundbars available.
Everyday users consistently praise the XIO's immersive Atmos experience, deep bass that often eliminates the need for a separate subwoofer, and the convenience of the KEF Connect app, while noting the lack of rear speakers and the requirement to buy a separate wireless subwoofer for extra low-end punch.
“Rich, detailed sound with deep, tuneful bass”

“Trueplay makes the room sound perfect, even on Android”

“Bluetooth 5.3 streaming works flawlessly”


XIO delivers higher power and true Atmos, whereas Sonos focuses on ease of use and ecosystem integration.