KEF XIO Soundbar - The Perfect All-in-one Atmos Solution?

This is the Xio sound bar from KEF, a British audio company that has been in the high-fidelity audio game for more than 60 years. This soundbar isn't like your usual soundbar. There are a few key features and three unique selling points that make it stand out and possibly surpass the competition. However, there is something really important you need to know before you proceed and add to the cart.

Sound Quality

Typically, in videos like this, I start with design, but this time I want to start with the sound, and you'll see why. A lot of soundbars promise immersive audio, that's a good way to sell products. But this one delivers in a way you have to hear to believe. Out of all the Atmos soundbars I've tested, this one delivers the best height and spatial audio soundstage to date, standalone. And what I mean by that is that if you sit directly in front of the Xio,  you can clearly hear sounds to the left and right of you, as if there are speakers parallel to where you're sitting. 

I was playing The Last of Us 2 on my PS5, and some of the sounds in that game freaked me out. Because sometimes it sounds like the clickers are right next to you. On the vertical audio side of things, when watching Atmos content, it sounds like there are sound sources positioned at a 45-degree vertical angle to the left and right from where I sit to watch TV. And it's really present and noticeable. I'm impressed by KEF XIO's ability to project the audio so precisely.

Speakers & audio tech

The Xio has been designed from the ground up for Spatial audio; it even utilises what KEF calls their Music Integrity Engine, a DSP algorithm for adaptive audio placement and virtualisation. You can also emulate this using Dolby or DTS X.  It does, of course, sound best when playing back proper Atmos, DTS X and 360 Reality Audio. Here's the tech magic behind the scenes of this soundbar. The Kef Xio is officially a 5.1.2 channel soundbar. It features 12 Class D amplifiers, with 8 dedicated to high frequency and mid-range, and 4 to bass. And these amps power three forward-facing UNI-Q MX drivers, which are mini versions of the iconic UNI-Q drivers that KEF uses on their LSXII speakers. Put simply, there's a high-frequency cone at the centre and a mid-frequency cone. It's an all-in-one, but with the help of a decoupler, they can operate independently.

There are also two outward-facing drivers & three more UNI-Q MX drivers for the overhead channels, and then there are four interesting P185 LF drivers with P Flex. These are in left and right pairs and placed back to back & because they're set up like this, they reduce unwanted vibrations using KEF's Velocity control technology. Also known as VECO. It's pretty complicated, but what you need to know is that this improves the resonance and control of the bass frequencies.  It's the exact same technique KEF uses on their KC62 and 92 dedicated subwoofers. And in case you were wondering, the max sound pressure level here is 102db and the amplifier output power is 820 W. And I will return to the bass and discuss how it sounds. Don't worry.

Design

So, sound was the first of the three things that separate this XIO from many soundbars. Here's the second: there's something special about this design that isn't immediately obvious. Many soundbars today are designed to be heard and not seen so much. This is a good approach that many people appreciate. However, there will be some who want something that looks classy, premium, like a luxury item, a statement piece…but also something with soft lines that doesn't look intrusive.

And that is what KEF is going for here. There are two colours: Slate Black & Silver Grey. The majority of the Xio is wrapped in this acoustic fabric. And I really like how the fabric wraps around and even under the left and right edges. It just looks excellent. You also have a circular dip in the middle where the bass drivers meet. The body is made of premium metal, and it features a heads-up display information at the top. Many soundbars no longer have these features. That definitely differentiates the Xio quite a bit.

However, take a look at this: this is what really sets the Xio apart. Thanks to the positioning of the Uni Q MX drivers the XIO can be wall-mounted upright or flat against the wall. It can adapt its sound to this orientation. This is brilliant because the Xio when flat on a TV stand has a lot of depth but it’s quite flat, so when mounted to the wall in this way, it doesn't stick out too far under the TV, and it will look awesome. And a couple of things I need to know. This speaker is a heavyweight, weighing 10.5 kg. A solid wall would be ideal. The good news is that KEF does throw the wall mounting brackets in the box. 

When it comes to controls. There's a control panel located at the top or on the front, depending on how you set it up. It has these nicely recessed buttons and backlighting. Which is excellent for darker rooms. You get a decent remote control with it, which has all the basic functions and access to two EQs; more on that in a moment. And yes, there is an app. If you're familiar with KEF audio products, you will likely already have this app. We will look at that shortly, but first, let me show you the ports and buttons on the back.

Ports

The setup process for the XIO with a TV is straightforward: you simply use the HDMI input port from your TV's ARC or eARC port. Plug in the figure 8 power lead, and that's really it. However, there are a couple more options available, including optical audio.

There's also a BT pairing button on the back, which might be dangerously close to the reset button, but having BT as an option is nice.  There's also the option to wire in a Sub. You can also hardwire your internet connection if you prefer not to use WiFi. 

Software & Audiophile Options

The Xio is a modern WiFi speaker, but with a classic Hi-Fi luxury design. And KEF's app unlocks a lot of Xio's potential and will help stay future-proof with over-the-air updates. On the homescreen, you get quick access to switch between content sources. There's also fast access to HiFi streaming apps like Amazon Music, Qobuz and Tidal. And then there's Spotify, which charges the same as the others but doesn't offer any HiRes. There's a dedicated radio and podcast section, and if you've set up a hard drive on your local area network, you can access it via this UPnP feature. You can also use Chromecast to throw content to it over WiFi.

And there are numerous options and custom tweaks to explore within the settings. But this is what I like the most about the software. When you enter the EQ settings, there is an EQ wizard that allows the Xio to adjust the sound profile automatically using IPT Intelligent Placement Tech for you, based on the room size and position within the room. This is very convenient during the setup process, and this same technology can convert regular stereo into spatial audio.

But if you're a proper audiophile or know someone who is, then you're going to love this the most. You can create more EQ profiles, and if you want, you can enter Expert Mode here. This gives complete control over the sound signatures' treble trim, bass extension, and high-pass frequency. Additionally, if you have a sub, you can dial that in here as well. So unlike some other soundbars, the Xio caters for not just audio fans but also audiophiles.

There are many excellent soundbars available today. However, it's essential to note that some of those soundbars serve as gateways for the brands to upsell you additional products in the future. And there's nothing wrong with that. It’s nice to have those options. Kef Xio, on the other hand, isn't just a starting point. It's a complete audio solution that sounds incredible right out of the box, without needing any extra equipment. It is a fantastic all-in-one solution for individuals who appreciate high-quality audio but prefer to avoid the clutter and complexity of a full surround sound system.

Now, I promised to discuss the sound quality and bass in more detail. The bass on the Xio soundbar, by itself, is very impressive and ranks among the best I've tested. And it will be more than enough bass for most people. The audio's real strength lies in its clarity and spatial soundstage. Something that's really important to know is that EQ1 by default is Kef's signature sound, and EQ is a dedicated dialogue mode which boosts the vocal range up if you need it. The great news is that if you do want the room rumbling with bass when you're watching movies and listening to bass-heavy music, that is an option. You can connect a sub via the RCA subwoofer output or use the KW2 RX Receiver for rear wireless subwoofer functionality. So there are still options, but you might not need them.