We tested the KEF LS50 Meta bookshelf speakers!

The British brand KEF has been present in the market of audio and hi-fi products since 1961. The KEF brand name stands for “Kent Engineering and Foundry”. Raymond Cooke founded the company.

On the occasion of its anniversary, KEF launched the original LS50 speakers in 2012. These tripod speakers have been a huge success, so much so that they have since continued to manufacture without much change.

The company’s engineers don’t sit back, however, and the result is the fresh-looking LS50 Meta speaker.

Building and design

LS50-Meta-speakers

The LS50 Metas are no different from the original LS50, and in many ways they are not exactly the same. The Meta has a matte housing, which is also advantageous because it prevents the fingerprint and dust from appearing on it,
The shape and size of the cabinet is optimal and the curved front is made of polyester in combination with fiberglass and calcium carbonate – thus creating an impressively rigid and well-controlled foundation for Uni-Q technology, which is the company’s own development.

Some important features of KEF LS50 Meta:

-Maximum power 106dB

-Sensitivity 85dB

-Frequency transmission 79Hz – 28kHz

-Impedance 8 ohms

-Dimensions (height) 30.2 x 20 x 27.8 cm

-Weight 7.2 kg

The KEF LS50 Meta is the world’s first Metamaterial speaker with a 12th generation Uni-Q speaker. Two-way bass reflex system.

KEF-LS50-Meta-spekaer-colours
The rest of the speaker box is made of MDF, which is heavily stiffened and carefully damped to minimize resonances. The LS50 Metas is available in four colours – white, carbon black, titanium gray and Royal Blue Special Edition.

The thick, rigid speaker box provides adequate stability. The modern, clean exterior can be easily integrated into almost any style of room. It looks decorative and youthful.

The only obvious change from previous models was the rear panel. The holes in the mounting screws on the front baffle have disappeared, giving the speaker a nicer, more tidy look. The baffle is made of DMC compound, which together with the internal stiffeners reduces internal vibration. Thick MDF boards, thanks to CFD (Computational Fluid Dynamics) technology, delay turbulence and keep mid-ranges cleaner.

Using MAT-Metamaterial Absorption Technology, a maze-like system has been developed, resulting in a clearer, more natural, distortion-free sound.

With the help of MAT, the speaker successfully copes with the sound coming from the back of the 25 mm aluminum tweeter dome. In a conventional design, this sound usually flows into the chamber behind the dome, where it is mostly absorbed by the damping material. But some sound energy always bounces off the dome, causing distortion.

In this case, however, the backward sound passes through a system that looks like a plastic circular maze. It is layered and consists of 30 tubes, each of which takes on a different frequency. KEF claims that after combining the tubes, a wide range of frequencies – from about 600 Hz upwards – are recorded much more efficiently than with alternative methods. The result should be clearer, less distorted high. The reflex orifice has become wider so more air can flow in and out. The 130mm speaker was fixed to the front panel using screws. Both the Uni-Q membrane and the large magnet further improve the sound.

These are not particularly sensitive speakers, with a rated power of 85 dB / W / m, the minimum impedance is only 3.5 ohms, so it is worth associating them with a higher power amplifier.

The Meta speakers are only 30 cm high, so they are quite compact in size, but they may not need to be placed on a bookshelf or directly against the wall. They won’t sound bad if we do, but they will sound much better if they are placed 50cm away in a room, well away from the side walls.

Sound

We tested the LS50 Meta speaker pair in an average-sized living room. We paired the speakers with a Denon AVR X3700H home cinema receiver, which proved to be a good decision.
The acoustics of the room, according to our measurements, were ideal, which was due to the Art wood diffusers placed on the walls and the photo-printed sound-absorbing panels. Bass traps were placed in the corners so you didn’t have to worry about echoes, excessive bass.
It didn’t take long for us to notice that the LS50s were significantly improved over their predecessors. While the basic sound character has not changed, the newer models have provided clarity and subtlety that the original LS50s were not capable of at this level.
We experienced fine, accurate and detailed sound while listening to several musical genres. In the case of instrumental works, the different instruments were well separable.

These compact speakers, despite their size, produced surprisingly full-bodied, respectable sound.
Metamaterial technology seems to really work. These new KEFs sound much clearer and more sophisticated than before, especially at higher frequencies.
The large-scale dynamics are handled well and have considerable power. At very high volumes, they sometimes produced a slightly fainter production, but that wasn’t a serious mistake.

KEFs sound smooth and balanced, although it is not possible to cover the shortcomings of weak recordings, but their sound does not deteriorate.

The KEF Uni-Q design looks good, the LS50 Meta generates an extensive and tightly concentrated tone, and the sound spectrum stability is also perfect. The bass is also quite intense, of course, anyone who clings to wall-shattering, pounding bass should choose another speaker or get a subwoofer.

Conclusion

LS50-Meta-in a room

We’ve always loved the LS50s, and this new version takes their performance to a significantly higher level. We believe that KEF has made great strides with Metamaterial technology, and this is immediately noticeable in sound as well. These speakers deliver balanced, natural and clear sound, and you can expect distortion-free performance thanks to their rugged design and internal attenuation. We were also happy with the bass ranges, although for percussive, really serious bass, we would prefer a more powerful speaker. For optimal sound, it is very important to pair KEF speakers with a higher power amplifier. We heard detail-rich, dynamic and space-filling sounds, which was a really pleasant surprise with such a compact-sized speaker.

Written by Róbert Polgár