Sonos Arc Ultra vs KEF XIO

Which Soundbar Is Better?

Products

Sonos Arc Ultra
KEF XIO

Tested using Methodology v1.3

Updated Oct 24, 2025 06:17 PM

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Tested using Methodology v1.3

Updated Nov 18, 2025 02:59 PM

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  1. Recommended in 2 articles:
  2. All-In-One
  3. Dialogue

Our Verdict

Sonos Arc Ultra

KEF XIO

The KEF XIO is a much more expensive soundbar than the Sonos Arc Ultra, and for most people, that extra outlay probably isn't worth it. The KEF's physical design is certainly more arresting, with a stylish, industrial-like look, making a welcome change from the all-black-bars that most soundbars take. But performance-wise, the Sonos offers a more accurate frequency response and wider-feeling soundstage. That said, the KEF does make Atmos content seem a bit more immersive, although since both bars lack dedicated satellites, there's only so much immersion you can expect from either setup. The KEF does have Optical built in, while the Sonos needs an adapter to support Optical, which uses up an eARC port. But for most people who just want a good-sounding bar, the Sonos is a better value.

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Variants

  • Arc Ultra (Black)
  • Arc Ultra (White)
  • XIO (Silver Grey)
  • XIO (Slate Black)

Check Price

Black
Arc Ultra
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Silver Grey
XIO
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White
Arc Ultra
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Slate Black
XIO
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Main Differences for
Mixed Usage

Threshold 

0.10

Mixed Usage 
 

0.0
0.0
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Full Comparison

Design

Style - Bar  

Style photo - bar 
 

Sonos Arc Ultra Style photo - bar Sample

SAMPLE

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KEF XIO Style photo - bar Sample

SAMPLE

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Show Text 

Style - Subwoofer  

Style photo - sub 
 

Sonos Arc Ultra Style photo - sub Sample

SAMPLE

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KEF XIO Style photo - sub Sample

SAMPLE

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Sub Wireless 
 

Locked
Locked

Enclosure 
 

Locked
Locked
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Style - Satellites  

Style photo - satellites 
 

Sonos Arc Ultra Style photo - satellites Sample

SAMPLE

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KEF XIO Style photo - satellites Sample

SAMPLE

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Satellite Wireless 
 

Locked
Locked
Show Text 

Dimensions - Bar  

Dimensions photo - bar 
 

Sonos Arc Ultra Dimensions photo - bar Sample

SAMPLE

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KEF XIO Dimensions photo - bar Sample

SAMPLE

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Width  

Lock" (Lock cm)
Lock" (Lock cm)

Height  

Lock" (Lock cm)
Lock" (Lock cm)

Depth  

Lock" (Lock cm)
Lock" (Lock cm)
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Dimensions - Subwoofer  

Dimensions photo - sub 
 

Sonos Arc Ultra Dimensions photo - sub Sample

SAMPLE

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KEF XIO Dimensions photo - sub Sample

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Width  

N/A
N/A

Height  

N/A
N/A

Depth  

N/A
N/A
Show Text 

Dimensions - Satellites  

Dimensions photo - satellites 
 

Sonos Arc Ultra Dimensions photo - satellites Sample

SAMPLE

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KEF XIO Dimensions photo - satellites Sample

SAMPLE

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Width  

N/A
N/A

Height  

N/A
N/A

Depth  

N/A
N/A

Mounting 
 

Bar Mounting Holes 
 

Sonos Arc Ultra Bar Mounting Holes Sample

SAMPLE

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KEF XIO Bar Mounting Holes Sample

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Satellite Mounting Holes 
 

Sonos Arc Ultra Satellite Mounting Holes Sample

SAMPLE

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KEF XIO Satellite Mounting Holes Sample

SAMPLE

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Mountable Bar 
 

Locked
Locked

Bar Brackets Included 
 

Locked
Locked

Mountable Satellites 
 

Locked
Locked

Satellite Brackets Included 
 

Locked
Locked
Show Text 

Build Quality 
 

N/A
N/A

Build quality photo 
 

Sonos Arc Ultra Build quality photo Sample

SAMPLE

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KEF XIO Build quality photo Sample

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In The Box 
 

In The Box photo  
 

Sonos Arc Ultra In The Box photo  Sample

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KEF XIO In The Box photo  Sample

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Show Text 
Sound

Stereo Frequency Response 
 

N/A
N/A

Stereo Setup 
 

Sonos Arc Ultra Stereo Setup Sample

SAMPLE

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KEF XIO Stereo Setup Sample

SAMPLE

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Raw Frequency Response  

Sonos Arc Ultra Raw Frequency Response Sample

SAMPLE

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KEF XIO Raw Frequency Response Sample

SAMPLE

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Frequency Response Small  

Sonos Arc Ultra Frequency Response Small Sample

SAMPLE

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KEF XIO Frequency Response Small Sample

SAMPLE

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Channels 
 

Locked
Locked

Tested Preset 
 

Locked
Locked

Slope 
 

Lock
Lock

Standard Error 
 

Lock dB
Lock dB

Low-Frequency Extension 
 

Lock Hz
Lock Hz

High-Frequency Extension 
 

Lock kHz
Lock kHz
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Stereo Frequency Response With Preliminary Calibration 
 

N/A
N/A

Frequency Response Calibrated  

Sonos Arc Ultra Frequency Response Calibrated Sample

SAMPLE

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KEF XIO Frequency Response Calibrated Sample

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Suggested Preset 
 

Locked
Locked

Suggested Bass Setting 
 

Lock
Lock

Suggested Treble Setting 
 

Lock
Lock

Slope 
 

Lock
Lock

Standard Error 
 

Lock dB
Lock dB

Low-Frequency Extension 
 

Lock Hz
Lock Hz

High-Frequency Extension 
 

Lock kHz
Lock kHz
Show Text 

Stereo Soundstage 
 

N/A
N/A

Crosstalk  

Sonos Arc Ultra Crosstalk Sample

SAMPLE

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KEF XIO Crosstalk Sample

SAMPLE

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Crosstalk Error 
 

Lock dB
Lock dB
Show Text 

Stereo Dynamics 
 

N/A
N/A

Dynamic Range Compression  

Sonos Arc Ultra Dynamic Range Compression Sample

SAMPLE

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KEF XIO Dynamic Range Compression Sample

SAMPLE

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SPL @ Max Volume 
 

Lock dB SPL
Lock dB SPL

DRC @ 90dB 
 

Lock dB
Lock dB

DRC @ Max Volume 
 

Lock dB
Lock dB
Show Text 

Center 
 

N/A
N/A

Center Setup 
 

Sonos Arc Ultra Center Setup Sample

SAMPLE

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KEF XIO Center Setup Sample

SAMPLE

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Frequency Response  

Sonos Arc Ultra Frequency Response Sample

SAMPLE

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KEF XIO Frequency Response Sample

SAMPLE

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Localization 
 

Locked
Locked

Slope 
 

Lock
Lock

Std. Err. 
 

Lock dB
Lock dB

SPL @ Max Volume 
 

Lock dB SPL
Lock dB SPL

Weighted THD @ 80dB 
 

Lock
Lock

Weighted THD @ Max Volume 
 

Lock
Lock
Show Text 

Surround 5.1 
 

N/A
N/A

Surround Setup 
 

Sonos Arc Ultra Surround Setup Sample

SAMPLE

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KEF XIO Surround Setup Sample

SAMPLE

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Frequency Response  

Sonos Arc Ultra Frequency Response Sample

SAMPLE

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KEF XIO Frequency Response Sample

SAMPLE

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Localization 
 

Locked
Locked

Slope 
 

Lock
Lock

Std. Err. 
 

Lock dB
Lock dB

SPL @ Max Volume 
 

Lock dB SPL
Lock dB SPL

Weighted THD @ 80dB 
 

Lock
Lock

Weighted THD @ Max Volume 
 

Lock
Lock

7.1 Rears 
 

Locked
Locked
Show Text 

Height (Atmos) 
 

N/A
N/A

Height Setup 
 

Sonos Arc Ultra Height Setup Sample

SAMPLE

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KEF XIO Height Setup Sample

SAMPLE

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H Frequency Response  

Sonos Arc Ultra H Frequency Response Sample

SAMPLE

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KEF XIO H Frequency Response Sample

SAMPLE

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Localization 
 

Locked
Locked

Slope 
 

Lock
Lock

Std. Err. 
 

Lock dB
Lock dB

SPL @ Max Volume 
 

Lock dB SPL
Lock dB SPL

Weighted THD @ 80dB 
 

Lock
Lock

Weighted THD @ Max Volume 
 

Lock
Lock
Show Text 

Sound Enhancement Features 
 

N/A
N/A

Room Correction 
 

Locked
Locked

Dialogue Enhancement 
 

Locked
Locked

Auto-Volume/Night Mode 
 

Locked
Locked

Subwoofer Level Adjustment 
 

Locked
Locked

Bass Adjustment 
 

Locked
Locked

Treble Adjustment 
 

Locked
Locked

EQ 
 

Locked
Locked

Surround Level Adjustment 
 

Locked
Locked

Rear Level Adjustment 
 

Locked
Locked

Height Level Adjustment 
 

Locked
Locked

Virtual Surround 
 

Locked
Locked
Show Text 
Connectivity

Inputs/Outputs - Bar 
 

Physical Connections Bar Photo 1 
 

Sonos Arc Ultra Physical Connections Bar Photo 1 Sample

SAMPLE

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KEF XIO Physical Connections Bar Photo 1 Sample

SAMPLE

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Physical Connections Bar Photo 2 
 

Sonos Arc Ultra Physical Connections Bar Photo 2 Sample

SAMPLE

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KEF XIO Physical Connections Bar Photo 2 Sample

SAMPLE

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Optical Audio In 
 

Locked
Locked

HDMI Out 
 

Locked
Locked

HDMI 2.1 Class Bandwidth 
 

Locked
Locked

Full HDMI In 
 

Locked
Locked

Analog Audio In 3.5mm (Aux) 
 

Locked
Locked

RCA In 
 

Locked
Locked

USB for Files 
 

Locked
Locked

Ethernet 
 

Locked
Locked

Subwoofer Output 
 

Locked
Locked
Show Text 

Audio Format Support: ARC/eARC 
 

N/A
N/A

Dolby Atmos 
 

Locked
Locked

Dolby Digital 
 

Locked
Locked

Dolby Digital Plus 
 

Locked
Locked

Dolby TrueHD 
 

Locked
Locked

DTS 
 

Locked
Locked

DTS:X 
 

Locked
Locked

DTS-HD MA 
 

Locked
Locked

PCM Channels 
 

Locked
Locked
Show Text 

Audio Format Support: HDMI In 
 

N/A
N/A

Dolby Atmos 
 

Locked
Locked

Dolby Digital 
 

Locked
Locked

Dolby Digital Plus 
 

Locked
Locked

Dolby TrueHD 
 

Locked
Locked

DTS 
 

Locked
Locked

DTS:X 
 

Locked
Locked

DTS-HD MA 
 

Locked
Locked

PCM Channels 
 

Locked
Locked
Show Text 

Audio Format Support: Optical 
 

N/A
N/A

Dolby Digital 
 

Locked
Locked

DTS 
 

Locked
Locked

PCM Channels 
 

Locked
Locked
Show Text 

Audio Latency: ARC 
 

N/A
N/A

ARC Latency Video  

Sonos Arc Ultra ARC Latency Video Sample

SAMPLE

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KEF XIO ARC Latency Video Sample

SAMPLE

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PCM-2.0 ch 
 

Lock ms
N/A

PCM-5.1 ch 
 

Lock ms
N/A

Dolby MAT (PCM) Atmos 
 

Lock ms
Lock ms

Dolby Digital 
 

Lock ms
Lock ms

Dolby Digital Plus 
 

Lock ms
Lock ms

Dolby Digital Plus Atmos 
 

Lock ms
Lock ms
Show Text 

Audio Latency: HDMI In 
 

N/A
N/A

HDMI Latency Video  

Sonos Arc Ultra HDMI Latency Video Sample

SAMPLE

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KEF XIO HDMI Latency Video Sample

SAMPLE

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PCM-2.0 ch 
 

N/A
N/A

PCM-5.1 ch 
 

N/A
N/A

Dolby MAT (PCM) Atmos 
 

N/A
N/A

Dolby Digital 
 

N/A
N/A

Dolby Digital Plus 
 

N/A
N/A

Dolby Digital Plus Atmos 
 

N/A
N/A
Show Text 

Audio Latency: Optical 
 

N/A
N/A

Optical Latency Video  

Sonos Arc Ultra Optical Latency Video Sample

SAMPLE

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KEF XIO Optical Latency Video Sample

SAMPLE

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PCM-2.0 ch 
 

N/A
N/A

Dolby Digital 
 

N/A
N/A
Show Text 

Video Passthrough To TV 
 

N/A
N/A

1080p Max Refresh Rate 
 

Locked
Locked

1080p @ 4:4:4 Max Refresh Rate 
 

Locked
Locked

4k Max Refresh Rate 
 

Locked
Locked

4k @ 120Hz @ 10-Bit 
 

Locked
Locked

4k @ 4:4:4 Max Refresh Rate 
 

Locked
Locked

8k Max Refresh Rate 
 

Locked
Locked

HDR10 Passthrough 
 

Locked
Locked

HDR10+ Passthrough 
 

Locked
Locked

Dolby Vision Passthrough 
 

Locked
Locked

HDMI Forum VRR Passthrough 
 

Locked
Locked

FreeSync Passthrough 
 

Locked
Locked

G-SYNC Passthrough 
 

Locked
Locked

ALLM Passthrough 
 

Locked
Locked
Show Text 

Wireless Playback 
 

N/A
N/A

Bluetooth 
 

Locked
Locked

Wi-Fi Playback 
 

Locked
Locked

Chromecast built-in 
 

Locked
Locked

Apple AirPlay 
 

Locked
Locked

Spotify Connect 
 

Locked
Locked
Show Text 
Additional Features

Interface 
 

Interface photo 
 

Sonos Arc Ultra Interface photo Sample

SAMPLE

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KEF XIO Interface photo Sample

SAMPLE

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Display 
 

Locked
Locked
Show Text 

Bar Controls 
 

Controls photo 
 

Sonos Arc Ultra Controls photo Sample

SAMPLE

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KEF XIO Controls photo Sample

SAMPLE

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Show Text 

Remote  

Remote photo 
 

Sonos Arc Ultra Remote photo Sample

SAMPLE

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KEF XIO Remote photo Sample

SAMPLE

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Show Text 

Voice Assistants Support 
 

Amazon Alexa 
 

Locked
Locked

Google Assistant 
 

Locked
Locked

Apple Siri 
 

Locked
Locked

Microphone Mute 
 

Locked
Locked
Show Text 

Check Price

Black
Arc Ultra
SEE PRICE
BestBuy.com
Silver Grey
XIO
SEE PRICE
BestBuy.com
White
Arc Ultra
SEE PRICE
BestBuy.com
Slate Black
XIO
SEE PRICE
BestBuy.com

Sonos Arc Ultra

KEF XIO

Comments

  1. Comparison

Sonos Arc Ultra vs KEF XIO: Main Discussion

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