Design and Engineering: Minimalist Aesthetics, Maximalist Tech
KEF’s signature Uni-Q drivers—a staple in their high-end speakers—take center stage here, but reimagined. The XIO features five Uni-Q MX drivers: three forward-facing and two upward-firing for Dolby Atmos effects. These aren’t standard drivers; they utilize a dual-diaphragm design with a mechanical crossover, allowing high frequencies to operate independently for pinpoint accuracy.
The real surprise? Four rectangular “P185” bass drivers (51x180mm) replace traditional circular units, providing the radiating area of 10cm woofers while maintaining the bar’s sleek 60mm profile. This engineering lets the XIO deliver shockingly deep bass without a separate subwoofer—a rarity in single-bar designs.
Yet compromises emerge. Unlike competitors like the Sennheiser Ambeo Soundbar Max, the XIO lacks any display. Volume adjustments or input changes require tapping near-invisible buttons that blend into the matte-black chassis. During testing, we frequently reached for the companion app just to verify settings—a frustrating experience at this price point.
Sonic Performance: Precision Meets Cinematic Thrills
Where the XIO truly shines is sound quality. Testing John Wick: Chapter 4’s Rome car chase scene revealed astonishing separation: screeching tires tracked laterally across the room while gunfire snapped with tactile intensity. The upward-firing drivers created genuine overhead effects as bullets ricocheted off pillars—a Dolby Atmos showcase.
Music performance stunned us equally. Playing Radiohead’s “Codex,” Thom Yorke’s vocals floated with haunting clarity, while the piano’s decay resonated with studio-like authenticity. Switching to Billie Eilish’s “Bury a Friend,” the XIO handled subterranean bass lines without muddiness, each synth layer distinct yet cohesive.
Key Audio Advantages:
- Bass Precision: The P185 drivers deliver tight, textured lows—no boomy overhang
- Immersion: Height effects outperform most soundbars at twice the price
- Musicality: Rare ability to reveal studio nuances in complex tracks
Connectivity Constraints: The HDMI Dilemma
The XIO’s Achilles’ heel is connectivity. With just one HDMI eARC port, one optical input, and Bluetooth, it trails behind rivals. Gamers face a particular headache: without HDMI passthrough, you can’t connect consoles directly to the soundbar for lag-free audio. During testing, we had to choose between our PlayStation 5 and 4K Blu-ray player—a baffling compromise at £2,500.
The Competition: XIO vs. Sennheiser Ambeo Max
Compared to the former champion Sennheiser Ambeo Soundbar Max (£2,400), the XIO trades brute force for finesse:
Feature
KEF XIO
Sennheiser Ambeo Max
Bass Impact
Tighter, more controlled
Room-shaking but less precise
Height Effects
More accurate object tracking
Wider but diffuse
Connectivity
1x HDMI eARC, optical, Bluetooth
3x HDMI, optical, Bluetooth
Display
None
OLED status panel
The Verdict: Who Should Buy It?
For audiophiles seeking reference-grade sound in minimalist packaging, the KEF XIO soundbar is a revelation—its Uni-Q drivers deliver unmatched clarity that shames most competitors. Movie buffs will adore its immersive Atmos rendering, while music lovers can finally enjoy studio subtleties from a single bar. Yet gamers and multi-device users should pause; the lack of HDMI passthrough is a genuine frustration at this price. If pristine audio outweighs connectivity needs, the XIO reigns as the new high-end champion. Experience it at a KEF dealer before deciding.
Must Know
What audio formats does the KEF XIO support?
The XIO supports Dolby Atmos, DTS:X, and high-resolution streaming up to 24-bit/192kHz via Tidal Connect, Qobuz, and Amazon Music. Its HDMI eARC ensures lossless audio from compatible TVs and players.
Can you add a subwoofer to the KEF XIO soundbar?
No. Unlike many premium soundbars, the XIO lacks a subwoofer output. KEF engineered its four P185 bass drivers to provide full-range sound without external subs—a deliberate design choice that delivers tight bass but limits upgrade potential.
Does the KEF XIO work with voice assistants?
While the soundbar lacks built-in Alexa or Google Assistant, it integrates seamlessly with existing ecosystems via Bluetooth. You can stream from voice-controlled devices but can’t issue commands directly to the bar.
How does the KEF XIO handle dialogue clarity?
During testing, dialogue remained intelligible even during chaotic scenes like Dune’s sandworm attacks. The center-focused Uni-Q drivers minimize vocal muffling—a common soundbar flaw—without needing a “night mode.”
Is the KEF XIO worth £2,500?
For audio purists, absolutely. Its musical fidelity rivals separates systems costing far more. However, casual listeners might find similarly immersive performance from Sonos Arc (£899) or Samsung HW-Q990D (£1,699) with fewer connectivity compromises.
