To Doug Schneider,

It was with a great deal of curiosity and interest that I read your review of the new KEF LS50 Meta loudspeaker.

I have five of the original LS50s in my theater and, having read the sales pitch, I was most curious how the Meta would measure. Pulling up the old SoundStage! Network measurements for the LS50 to compare, it looked as though you were just measuring another LS50. The differences, for the most part, could be put down to standard production variations as much as to any new refinements.

It was interesting that they really couldn’t improve the cabinets at this price point, but not altogether surprising.

The biggest difference I can see in KEF’s literature is that their Metamaterial Absorption Technology virtually eliminates the back wave of the tweeter and reduces total harmonic distortion (THD) by around 0.03%. So that’s, maybe, a 4dB reduction. I’d consider that to be no more than an incremental improvement.

The LS50 has as close to the ideal temporal response as you can get with a passive speaker. That being said, it’s not perfect -- it can be improved by forgoing the passive crossover and biamping the speaker with a digital speaker processor. Using FIR and steep IIR filters, you can tweak these speakers to be as close to perfect as they can be. Add in some serious digital signal processing (DSP) like Dirac or DEQX and you will have perfect group-delay response.

In other words, the improvement in sound quality from the slight reduction in THD afforded by the Meta can easily be matched by using room correction and an effective DSP crossover with the original LS50s. Yes, this is a more expensive way to go, but it does offer greater control than you can get with the wireless version of the Meta. Whether the sound would be drastically better is another story.

One thing that does suck is that KEF doesn’t offer a single LS50 Wireless II to use as a center speaker, so that model is out for me.

So, as it stands, I’m only three stereo Purifi Audio Eigentakt amps (for left, center, and right) and a couple of DSP units away from having as great a surround system as you can get with my LS50s. I’m good with that! And no, I won’t be going the active route with the surround speakers, either.

So, Doug, thanks for another very informative review.

All the best,
Jeff Henning
United States

Thanks for reading and responding. It’s true the differences between the LS50 and LS50 Meta are small, so there probably are other ways to improve the sound of a system rather than swapping out the older model for the newer one. Still, I think fans of the original will be pleased by the small improvements and, in many cases, will want to make the move. . . . Doug Schneider