REVIEW: KEF LS50 WIRELESS LOUDSPEAKER SYSTEM
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The Complete System
I was born to be the son of an audiophile.
While I missed most of the 70s, arriving in his world of turntables, cables and speaker boxes stuffed with drivers in 1978, little did my father know that within a decade he’d nurture what for me, is still a life-long audio passion.
A passion that’s still excited by a pair of affordable KEF LS50 Wireless speakers that have been playing in my room for some time now. These compacts redefine their genre and they remind me how my audio journey began.
As my father tinkered with his hi-fi gear tuning it to suit his room and his ears, it occurs to me now that he wasn’t a man who obsessed over specifications.
Sure, he paid respect to the technicalities of audio parameters including frequency response, measured distortion, and crossover points. But he didn’t think they were the final arbiters of sound.
Along the way, I subconsciously imbibed my father’s audio philosophy without him even realising what was seeping into my mind.
Upon arrival, I didn’t obsess about the LS50 Wireless’ technical parameters, preferring to simply scan the owner’s manual briefly before wiring and firing these wee dynamos.
In dad’s day, it was DIY audio on a shoestring budget; immensely popular around the world at the time. Researching the period, the 70’s was a golden age for audio with novel designs and booming sales.
Brands like Rogers, Spendor, Harbeth, and many others were steaming ahead in the world of loudspeaker design. Raymond Cooke, the electrical engineer that founded KEF in 1961, like many UK audio luminaries, would go on to commercial success based upon a steep learning curve forged at the BBC.
An audio system back in the 70s may have consisted of a Radford SC22 pre-amplifier and STA-25 valve amplifier, Garrard 301 or Thorens 124 turntable, either with an SME3009 tonearm, Shure V15 cartridge and of course, the now legendary LS3/5A BBC designed monitor speakers (which went on to sell more than 60,000 pairs). The only weak link was the preamplifier. Compared to contemporary designs, the older preamps sounded opaque and certainly lacked detail.
Even today, in top condition this system that many audiophiles still use but with a modern pre-amp, is still at the top of its game with an uncannily realistic mid-range, superb timing and a musicality that is truly gob-smacking.
KEF was one of the first manufacturers to embrace computer aided design for loudspeaker design and development. It was from this early research and advances in design and materials technology that would result in a loudspeaker that would become one of KEF’s proudest achievements to date, and celebrating KEF’s 50th anniversary, the LS50.
Inspired by the LS3/5A, the LS50 requires little introduction these days, regarded by most as a speaker that is ridiculously good, particularly for its size and footprint.
When rumours started circulating a couple of years ago, that the LS50 may be released in an ‘active’ form, it was hardly surprising. In fact, it made perfect sense. Compact, highly efficient amplifiers, DSP technology, and streaming platforms have become the norm, and combining all this connectivity with a speaker that represents outstanding value for money and proven popularity will likely prove a smart commercial decision.
So, what is it?
Put simply, almost a complete system. It could be your first, or your last HiFi system. I’ll come back to that.
KEF took the original LS50 and grafted in a preamplifier with a bunch of DSP functionality, DAC, amplifiers, and a network streamer.
That means, no additional speaker cables to purchase or obsess over, and more importantly, no more room-intrusive racks of gear.
You can connect the LS50 Wireless via your smartphone or tablet, either via Wi-Fi or Bluetooth (aptX) and stream Tidal, Spotify or your choice of local music. Or you can make the connection via USB or Toslink directly to your PC or laptop, or even your TV, taking advantage of the built-in 192/24 DAC.
Finally, you can connect any source, a turntable for example, via the AUX Line Level input.
At the time of writing, Tidal and Spotify integration has not yet been released for the ‘LS50 Wireless’ app for Android (4.1+) or iOS (8.0+). Maybe not a deal breaker for many, but so many of my music playlists are stored on these platforms now. We’re assured though, it is coming.
It’s also a shame that the inclusion of a Roon endpoint didn’t make the final feature list. As far as music library management, control, and multi-room streaming across non-brand specific products, Roon has cornered the market. Perhaps more of a personal indulgence than a mainstream necessity, but more on that later.
While ‘Wireless’ is the key marketing message here, in my mind it’s the active component of the LS50, rather than the wireless connectivity that is the major selling point. ‘LS50 Active’ would have been a more compelling title, at least in my opinion.
It’s offered in a choice of colours, including Titanium Grey/Red, Gloss Black/Blue, and Gloss White/Copper. KEF say, they’re “interior design friendly”.
In Australia, the LS50W retails for $3,799. Wander into a specialist store and add up the cost of a quality integrated amplifier with DAC and network streamer built-in, a pair of quality stand-mount speakers, plus cables, and the true value proposition of the LS50 Wireless becomes obvious.
No gurus required
Setup could not be easier. You won’t be speed dialling your trusted guru to make the connections with the LS50 Wireless.
Unbox and simply place each speaker on a stand or sideboard. Connect power to each speaker, and plug the supplied Cat6 Ethernet cable from the right speaker to the left. Done.
Turn on, and follow the instructions from the LS50 Wireless app to make the Wi-Fi connection. In my case, I had to repeat this process twice to successfully ‘on-board’ the speakers.
Specs and detail
Like the passive sibling, the LS50W uses the proprietary Uni-Q array, 5.25” single point source driver.
Without the compromises within a passive crossover to contend with, KEF has been able to highly tune the driver even further in the LS50W. With no losses or introduced distortion from crossover components, complete control of each driver’s output, crossover frequencies and phase via the DSP, you quickly discover why ‘active’ is a compelling step forward in the HiFi market.
The mid-woofer is powered by a 200w Class D amplifier, while the centre mounted tweeter is supplied by a 30w Class A/B amplifier.
At best (depending on DSP settings), per KEF’s specifications, the LS50 Wireless offers a frequency response of 45Hz to 28kHZ (+/- 3dB). For those baulking at the lower frequency response, remember this is a small driver and cabinet, there’s simply no defying physics. It’s no wonder there’s also a subwoofer output.
On the rear of the right speaker you can choose between desk/sideboard, or stand mounting, and wall/free-space positioning. Each choice will adjust the on-board DSP tuning accordingly. Via the app, more tuning is available, in either Basic or Advanced mode, along with the ability to tell the LS50W if you’re using them in bright/hard-surfaced room, mildly damped room, or heavily damped room. These settings and their corresponding tuning really do make a difference, so be sure to experiment.
Handy tip: to comply with European ErP requirements, the LS50W will go into standby mode after 20 minutes of inactivity. This bugged me right away, but can be extended to 60 minutes by pressing and holding the Desk/Stand button on the right speaker for 5 seconds. You’ll want to do this right away.
Living with LS50 Wireless
All too often, particularly with high-profile new products, loaner time for reviews is short, even just days. Not so this time. I wanted to live with these speakers and use them in a real-world application.
They would be with me for several weeks, starting life in my office where I spend most of my days. No critical listening really takes place here, but I still appreciate good sound between phone calls and courier deliveries.
An acoustician’s nightmare, my industrial styled office is L-Shaped, features polished floorboards, double brick walls, and not a rug or soft furnishing in sight.
Setting the LS50W room mode accordingly, they were set atop lead-shot filled Atacama stands and dropped into prime position.
The first experience would come via Wi-Fi connection and control via the LS50 Wireless app. My local music library is stored on a rackmount Synology NAS drive and served (in this case) via UPnP.
The app itself is simple and very easy to navigate, but feels more intuitive when playing local content from the device, rather than a network share. Scrolling through thousands of artists and even more albums via the network feels somewhat disconnected.
Moving to other UPnP apps (which fortunately allows you to use your preferred app of choice), felt a little more refined and improved the user experience for me. In fairness, the LS50W ‘app’ could be considered first generation, and will likely be updated by KEF and improve at a fast pace.
A few hours later I paired my desktop PC via Bluetooth AptX. This allowed more freedom as a source, and of course allowed me to use Roon. You know that feeling when you’ve been on a holiday and you climb back into your own bed for the first time?
Setting the output via Roon to Fixed Volume, having my review and audition playlists at hand, I’d now begin to get a better understanding of the LS50W’s capabilities.
From my desk about 4m from the speakers, the colour coded remote (in this case white, and maybe a bad long term choice) often seemed slow to respond to volume changes, at least in comparison to changes via the volume slider within the app.
Using the LS50W multiple times each day proved simple. Bluetooth would automatically re-pair upon powering up. Wi-Fi is not quite as reliable, and I did have to repeat the on-boarding process on one occasion.
How’s it sound?
The final week of listening was completed in my dedicated media room. A heavily damped, acoustically treated room that measures 7.1m x 5.5m x 2.7m.
I can say that the LS50 Wireless was just as at home in either room, particularly with the corresponding room mode DSP settings applied.
I was going to start off with a criticism of Bluetooth connectivity in regards to sound quality. But as I pondered my 11 pages of scribbled listening notes, something occurred to me. I’ve only ever reviewed Bluetooth AptX via headphones, portable speakers, and docks. The LS50W for me, highlighted the obvious limitations that still exists with this streaming method.
Quite simply, all products prior simply didn’t offer the full-scale bandwidth and resolution that the LS50W does. Compression was evident, along with a thin sound comparable in some cases to higher resolution MP3. Audiophiles will want to look to directly connected sources/devices. Other members of my family of course had no problem – oh to be so naïve to high-fidelity sound again. I’d be far better off financially!
Most of my auditioning would be completed via a DIY Arch Linux ARM running Roon Bridge connected via USB directly to the LS50W. This is my regular reference network player, typically paired to the EMM Labs DAC2X DAC.
I fired up my ‘Audition’ playlist on Roon, which is a combination of locally stored (NAS) music, along with some 16/44 and Masters sections from Tidal.
Like the predecessor, LS50 Wireless managed to construct a sound stage far greater in size than what such a small speaker should be capable of.
As I eagerly clicked through tracks, the capability of the built-in DAC, its transparency, resolution, and full-bodied sound became clear, so much so I had to remind myself I wasn’t using my DAC2X.
I recall the beauty of the LS50’s midrange, and Anne Bisson’s ‘In The Wee Small Hours’ reveals the breathtaking realism has not been lost in KEF’s amplification and processing of the incoming source.
Eva Cassidy’s ‘Stormy Monday’ is another example, capturing the stage placement, depth, live ambience, and honesty of the recording just as convincingly as any of the high-quality systems and speakers I’ve had through my room.
I was a bit of a late-comer to the Angus & Julia Stone appreciation society. They’ve become one of my go-to artists recently and the subtle textures and layer upon layer of harmonies are clearly defined in ‘Santa Monica Dream’.
There’s an apparent synergy that is achieved by default with the LS50 Wireless, and I’ve always thought that this is one of the hardest things to get right in audio. KEF has done all the hard work for you.
There are no speaker cables to add unintended coloration, the amps are in tune with the drivers, phase issues are virtually non-apparent. With much more control over the output, what you’re listening to is closer to what KEF’s engineers intended than ever before.
Track after track revealed a universal speaker that is energetic, lively, but displays confidence and authority. The 5.25” Uni-Q driver is in complete control.
While a subwoofer output exists, to review the LS50 Wireless with a sub wouldn’t be assessing the speaker’s capability within its intended application. Adding a subwoofer would of course provide more oomph and bottom end extension.
Glass Animals ‘Black Mambo’ – written by front man Dave Bayley and inspired by watching an episode of Breaking Bad, is intro’d via a series of bass sweeps. I’ve used this track on countless sets of speakers, and the coherence of the sweep is as balanced as my current reference, the Meridian DSP8000SE, which retails in Australia for $100,000. Not by any stretch of the imagination am I suggesting that the LS50W has the sheer output or digs as deep as the Meridian, but what it does do, it does extremely well.
The track that shall not be named, by Nils Lofgren, is impressive, but equally commensurate is the ‘Bass & Drum Intro’. Once again, LS50W demonstrates the amplifier’s ability to maintain control during the complexities of various drums and bass guitar all striving to be heard at the same time. When you consider the necessary compact size of the amplifiers, the absence of large power transformers and capacitor banks, you can’t help but be impressed.
When old meets new
As high-tech as KEF’s LS50 Wireless are, the humble LP’s return to glory means the connection of a turntable is likely to ensue. This was of interest to me, as anything connected to the line level AUX input is converted to 24/192 digital.
Perhaps grossly out of proportion from a monetary perspective, but connecting my TechDAS Air Force III turntable, via an RCM Sensor2 phono stage, would leave nowhere to hide for the analog to digital conversion process.
I’m pleased to say, not only were all the delicacies of Anne Bisson’s ‘September in Montreal’ from her Blue Mind LP left in-tact, but what followed was hour upon hour and LP upon LP of wonderful music.
It’s fair to say that digital technology has come a long way in recent years, and the supposed gap between the analogue and digital domains is decreasing rapidly.
Recently, there’s a lot of talk from audio journalists and publications that for Hi-Fi to survive, the products need to appeal to a broader audience; more affordable even. There’s merit to the argument, but if the high-end is the breeding ground for new technology that eventually filters down to the cheaper end of the market, then it’s an important part of the ecosystem.
KEF hasn’t buckled to market pressure for cheaper products. They’ve just made a smarter product. And by doing so, they’ve also managed to deliver BMW sound at Toyota pricing.
If I was starting my HiFi journey again, the KEF LS50 Wireless would be my first choice. Similarly, if I was downsizing from big floor-standing speakers and multiples of components, it would still be my choice.
The connectivity options are all apparent and plentiful. Sound quality is refined and reference grade.
The niggles relating to the user interface and app are likely to be improved by KEF via over-the-air software updates in time, or resolved now by using your choice of control app.
KEF’s LS50 Wireless really could be your first, or your last system. This new speaker will introduce loads more people to high-fidelity sound for a realistic and modest investment.
Whether you’re looking for a HiFi solution to handle your TV’s audio while being capable of wireless streaming for the whole family, or a dedicated stereo system in a small to medium living space, KEF LS50 Wireless ticks all the boxes.
It’s barely 2017, but we’ll be putting this one forward as a strong contender for Product of the Year.
KEF LS50 Wireless is available from Specialist Dealers.
For more information, visit the KEF brand page.