Review: KEF LSX Wireless Loudspeakers
These compact and stylish wireless speakers possess all the superb coherence and detail we’ve come to expect from KEF. John Pickford dispenses with the speaker cables.
KEF’s new LSX wireless loudspeakers are, in many respects, a scaled-down version of the company’s highly regarded LS50W wireless speaker system. I lived with the passive LS50s for several weeks a couple of years ago, borrowed from an audiophile friend who reckoned them to be the best standmount speakers at or anywhere near their price point. He wasn’wrong. At half the price of the wireless LS50s, these diminutive active speakers present
a genuinely attractive proposition, offering a great deal of flexibility in a neat, compact package.
Much of the KEFs’ versatility is down to their digital audio capabilities, and they come with Spotify Connect and Tidal apps built in. KEF’s Control app makes connecting to Wi-Fi simple and keeps up to date with all the latest firmware. The app, accessible via the supplied remote control, also allows for adjusting the speakers’ equalisation to tailor the sound for your room.
Hang on, I hear you cry, this is a vinyl magazine for vinyl people – we’ll have no talk of digital here! Well, aside from dyed-in-the-wool anachronistic luddites, most of us can enjoy our analogue vinyl alongside digital technology. I frequently check out albums on Spotify before shelling out for the record on vinyl.
As an active design, all the power amplification is built in to the speaker cabinets, negating the need for separate amplifiers and speaker cables. I should point out, however, that it’s not possible to plug in a turntable directly; the LSXs do not have on-board phono stage amps and connection is strictly wireless. Fortunately, there are an increasing number of Bluetooth-compatible turntables and phono stages available, so if you want to use the KEFs with your current vinyl spinner, you’ll need to invest in
a Bluetooth phono stage.
Besides the convenience of bespoke amplification and wireless connectivity, the main feature of these speakers is the 4.5″ Uni-Q driver. This is a scaled-down version of the unit found in the larger LS50 and is a coaxial design. This means the tweeter is situated in the centre of the driver, rather than placed separately on the front baffle, above (or below) the woofer, as most loudspeakers are configured.
The beauty of this topology is the speaker operates as a ‘point source’, so the sound emanates from a single spot. I am an avowed fan of this type of design, which is most famous for being used in Tannoy’s classic Dual Concentric speakers, such as the huge 15″ Berkeley HPDs I use as my reference monitors. The coaxial point source arrangement has several advantages over conventional multi-driver designs, offering potentially greater focus and coherence, as well as effectively eliminating phase issues that can arise with multi-driver systems.
Powered by two Class D amplifiers per speaker, delivering 70 watts to each woofer and 30 watts to each tweeter, the KEFs have ample power. Frequency response is also impressive, with highs extending up to 28kHz, and while the laws of physics prevent them from producing subsonics, the rear firing port helps them reach down to 52Hz in standard mode (no equalisation). If more low-end weight is required, a subwoofer can be connected.
With complete disregard for the KEFs’ bijou proportions, I cue up Cinnamon Girl by Neil Young and Crazy Horse and dial up the wick. The generous, dynamic sound I hear defies the speakers’ size, with a disproportionate sense of scale. Dual guitars churn out the song’s gnarly riff with the right amount of attack and body, straddling the soundstage to present a stereo image that extends beyond the confines of the cabinets. This track has a tendency to plod when replayed with big old bloated boomboxes, but the fleet-footed KEFs follow the natural groove with ample rhythmic drive.
Toning things down with a few tracks from Nick Drake’s sparsely recorded Pink Moon album, I again notice the well-defined leading edges of acoustic guitar, while lead vocals sound natural with none of the exaggerated chestiness warmer speakers can impart on this recording.
The new KEF LSX is an excellent addition to the Uni-Q equipped range and comes highly recommended to those with Bluetooth-compatible vinyl set-ups who also value the convenience of music streaming. Available in a variety of funky colours, their neat, stylish looks will appeal to those who would rather not have a stack of hi-fi boxes in their home.