KEF LSX Wireless Review
Headphones SG on 18th Dec 2018
After bringing hi-fi lovers the world over the multi-award-winning LS50 Wireless streaming system, KEF is back to show off high-quality, uniquely-designed audio solutions in a pint-sized package. The KEF LSX is an audio system that is comparable in quality to the current LS50 model and features a Bluetooth receiver capable of connecting to multiple devices, network streaming with easy setup and maintenance, and truly hi-fi amplification, all packed into a compact and colorful casing with several options that add a pop of color to any home.
In order to keep the scale small but comparable in technical and performance standards to the LS50, the KEF LSX packs fully wireless-capable speakers into significantly smaller cabinets with smaller Uni-Q driver arrays, and 200 Watts total of solely Class D module-powered amplification between the two speakers combined to power the mid/bass drivers. Because of the unconventional choice of using Class D modules to power the driver arrays, the LSX is incredibly power-efficient compared to many hi-fi speaker models currently on the market, and eliminates the need for big, bulky heat sinks in order to provide reliable, high-quality performance. These speakers run cool 24/7 and provide excellent sound without the need for extra, unnecessary heft. The real question now is, “Can KEF live up to the name they made for themselves with the LS50?”
Build Quality
The build of these speakers is unusual and unconventional in many ways - and that’s a good thing! The visual design is smart, innovative, and contemporary in nature without sacrificing quality in the slightest.These tiny cabinets are 24cm x 16cm x 18cm, with the soft curves on their baffles and a 19mm aluminium dome tweeter mounted in the center of the 11.5cm aluminium/magnesium mid/bass driver. Despite the small size, this tight design delivers powerful sound and drives it outward instead of pulling it back into the speaker. The color varieties are fun and eclectic enough to blend into any decor while adding a little bit of extra flair, as well.Considering the materials used in the LS50, the LSX’s plastic frame may seem like a slight downgrade to some, but considering the lack of need for heat sinks, it’s an appropriate choice for the casing of these cabinets. Luxurious Kvadrat fabric was chosen for covering the speakers to create different finishes on all color varieties, except for a glossy white variety of the LSX with a silver cone and red tweeter. Other colors include red with a red cone and silver tweeter, blue with a blue cone and silver tweeter, black with a silver cone and red tweeter, and olive green with a gold cone and red tweeter.KEF is well-known for their numerous design collaborations over the years, from the multi-colored KEF Muos designed by Ross Lovegrave to the “Nocturne by Marcel Wanders” edition of the wildly successful LS50 Wireless, not to mention KEF’s Porsche Design Space One headphones. This time, KEF collaborated with legendary British industrial designer Michael Young for the LSX. The olive green variety of these speakers, with its gold and red accents, also features Young’s signature subtly integrated into the design.Overall, in the design department, KEF offers a unique, yet completely contemporary take on compact speakers that still delivers realistic, high-quality sound without all the heft that hi-fi enthusiasts might expect from such a powerful package.
Playback, Streaming & Connectivity
The KEF LSX speakers are packed with features to make the most of. The speakers themselves can be connected either via Ethernet cable or 2.4GHz/5GHz wi-fi connectivity, and comes with tons of streaming options from within the KEF Stream app like Tidal and DLNA. Apple AirPlay 2 stream compatibility was just added recently, as well as Spotify Connect and aptX Bluetooth.While there are no RCA or USB Type B connections, the LSX does include optical inputs and 3.5mm audio inputs for connecting everything from TVs to portable devices. A subwoofer adds a pleasantly unexpected bass kick that you wouldn’t normally associate with such a tiny hi-fi package, and KEF’s Control app gives you full control over the EQ settings to tweak audio to your liking. Control also helps you get the LSX set up on your network, applies room settings, adds firmware updates, and lets you easily switch audio sources as you please.
The KEF LSX also comes with a remote to let you switch audio sources and adjust volume manually. Unfortunately, the LSX doesn’t sport the same on-speaker touch controls that its larger cousin, the LS50 does, but that’s a small complaint in the face of the nearly endless options presented for audio enjoyment customized to your liking.Having to use two apps, Stream and Control, may be a bit unusual for this compact set of speakers, but fortunately you can switch between the two within one app without having to open or close either one. At times, the Stream app has some issues with Tidal playback, but no other streaming services presented these little hiccups in stream quality. For a more stable connection, definitely make use of the Ethernet cable that comes with the speakers, but the wireless Bluetooth connection holds up beautifully.
Ultimately, it’s a trade between convenience and quality when it comes to connectivity: while the wireless connectivity is very convenient, do keep in mind the downscaling of audio will keep quality around 24-bit/48kHz, while the more stable Ethernet will cap at around 24-bit/96kHz, but the LSX will accept files up to 24-bit/192kHz in quality.When it comes to the LSX speakers themselves, each speaker has an active loudspeaker powered by drivers with their own discrete amps built in. Each mid/bass driver is powered by 70 Watt Class D amplification, with an additional 30 Watts of Class D amplification for a combined total of 200 Watts packed into two compact cabinets. It’s not the cream of the crop when it comes to power, but it’s certainly nothing to turn your nose up at, either! The use of Class D modules to power the drivers allows for much greater efficiency in energy use, as well as allowing for the design of a lightweight, cool-running speaker unhindered by heat sinks that would otherwise bulk up or weigh down the LSX. Like an Olympic athlete in their prime, the KEF LSX is lean, powerful, and amazing to behold.
Sound Quality
One competing model of speaker that comes to mind when comparing the audio quality of the KEF LSX is Naim’s Mu-So: a powerful, sleek set of successful hi-fi speakers in its own right. It’s a worthy competitor in this case and delivers excellent sound in its own right. However, the LSX presents a wider, fuller, more satisfying and realistic soundstage that allows music to truly flourish. While the quality of KEF’s sound production capabilities has been consistently high-quality, it’s quite a marvel that the LSX can provide such sound quality in spite of its compact frame. You have to hear it to believe how well this hi-fi system delivers.
Even with downscaled audio on a convenient wireless connection, the audio performance is staggeringly strong and reliable, and switching between sources is as easy as choosing options on an app or a press of a button on a remote. Mid tones seem to be especially prominent when listening to music, but there’s a clear, warm, and highly detailed quality to the highs and lows on the LSX, as well. Bass-lovers will absolutely love the subwoofer: it really kicks! Treble is crisp without being shrill or unpleasant to listen to, and the audio overall presents reasonable levels of attacks in its tonality, but never gets overbearing or unpleasant.
Audio playback of all kinds is satisfying and awash with beautiful textures, and a surprisingly wide soundstage propped up by KEF’s patent-pending “Music Integrity Engine” digital signal processing. This system helps to ensure pinpoint accuracy in phase coherence and time alignment when playing back audio, and keeps rhythms consistent and pleasant.
Even when playing lower-quality audio such as a standard CD-quality file at 16-bit/44.1kHz, the difference is hardly noticeable except to the highly-trained and discerning ear, and remains satisfying nonetheless. The technology of the Uni-Q drivers aids in uplifting the sound of even lower-quality audio like this to a level previously unthinkable, especially in speakers as compact as the LSX. The modest subwoofer being left out speaks to certain limits of the build and size, but is a small gripe compared to all of the features and quality packed into these speakers.
Some listeners may notice the limits of the LSX’s dynamic range during, say, extremely high-quality live performances, but that speaks more to the limits of the hardware packed into these speakers. While the LSX may not deliver the incredible range of a live symphony to your living room, it delivers surprisingly powerful, realistic sound in a lean and colorful package that’s chock-full of features to take advantage of. The variation being displayed in spite of the technical limits of the LSX’s size is nothing short of remarkable.
Our Verdict
So, do the KEF LSX speakers live up to the hype created by the LS50? Absolutely. There’s no doubt about it. KEF has once again delivered a unique and high-quality product that easily matches their achievements with the LS50.These scaled-down, lightweight KEF speakers don’t disappoint in the slightest. Though having two apps for use might be a bit much for controlling streaming and audio settings, you can’t deny that for such a tiny package, the LSX speakers are an incredibly innovative take on the best aspects of the extremely successful LS50 Wireless system, and a worthy successor to such an impressive speaker system.
However, unlike the LS50, the LSX does not come with RCA inputs or USB Type B connections available, and instead uses proprietary wireless connectivity between the two speakers, a feature not found on the LS50. Ethernet cables can also be used to connect the LSX speakers to one another, much like their larger cousins. The KEF LSX can play files up to 240bit/192kHz, but will downsample to 24-bit/48kHz when relying on wireless connectivity. If using the provided Ethernet cable for connection, these speakers will downsample instead to 24-bit/96kHz quality instead and the connection will have more stability to back the higher-quality audio playback.
Having so many streaming options and features incorporated into something entirely new and unique for a convenient, authentic, hi-fi experience for every lover of quality sound is an absolute gift. Better still, having all this packed into a sleek, minimalist package that’s popping with vibrant colors and none of the bulk expected with many hi-fi systems of a similar caliber? It’s nothing short of impressive on KEF’s part. The KEF LSX speakers command quite the presence despite their small stature, and deserve to be heard and enjoyed thoroughly.