KEF's New Tech is Real

[Deleted member 14468]

Hi,

Unlike many technologies trumpeted in hi-fi, I can say that I've seen KEF's new absorber tech first-hand and it's "real." What do I mean by real? It actually works. Search around -- you'll find the AES paper on it. I've also talked to the designers, and now even have a speaker here to measure. It also shows something interesting -- there was definitely something to the tapered tube technology that was invented by Laurence Dickie and pioneered in the Bowers & Wilkins Nautilus. KEF's MAT is essentially that done the KEF way.

Here's our new KEF video:

As for the tapered-tube technology, a day after we shot the KEF video, I interviewed Laurence Dickie:

Doug Schneider
SoundStage!

 

[SECA_alan]

That was very cool, I enjoyed both videos very much.

 

[TimVG]

The biggest drawback of the LS50 was the suboptimal crossover. Looking forward to the measurements.

 

[Kachda]

The wireless ii seems very convenient. Maybe I should just chuck out my constant dithering over which pre-amp/amplifier to buy and get a pair of these. Will be cheaper and more convenient to boot (the wire between speakers is optional too)

 

[Deleted member 14468]

The biggest drawback of the LS50 was the suboptimal crossover. Looking forward to the measurements.

I'm not sure what you mean by "suboptimal" -- can you elaborate?

Doug
SoundStage!

 

[TimVG]

I'm not sure what you mean by "suboptimal" -- can you elaborate?

Doug
SoundStage!

Hi Doug

Sure. There are some summation issues that negatively affect the direct sound, due to a suboptimal implentation of the crossover.

Correlates well with Amir's measurements: https://www.audiosciencereview.com/forum/index.php?threads/kef-ls50-bookshelf-speaker-review.11144/

There have been several (succesful) attempts made to improve upon the crossover, one example:

I've been unofficially told the issue has been taken care of in the newest version, fingers crossed.

 

[aarons915]

I've been unofficially told the issue has been taken care of in the newest version, fingers crossed.

It will be very interesting to see some apples to apples measurements of the LS50 to the meta from either Soundstage or ASR. I'm not a fan of all the marketing talk, I want to see measurements to see exactly what the change was. The biggest problem was the extra energy around 2k so if they managed to fix that through the meta material, then this would actually be a revolutionary technology. Maybe I'm a pessimist but like most things that are hyped up I'm sure the reality won't quite match the claims being made but we'll see.

 

[pozz]

Cool to see KEF using Earthworks microphones.

 

[TimVG]

The biggest problem was the extra energy around 2k so if they managed to fix that through the meta material, then this would actually be a revolutionary technology.

Doubt it. Better crossover is more than likely the answer.. But meta does sound cool.

 

[aarons915]

Doubt it. Better crossover is more than likely the answer.. But meta does sound cool.

CTA-2034 Measurements are up in the other thread from the whitepaper, they are much smoother athough a bit different than the originals in voicing. Also, a crossover isn't going to be flat on axis and have excess energy off-axis like the originals, it really pointed to some other problem with the geometry. I listened to the podcast on Darko from Jack Oclee Brown and there were other changes to the driver and crossover to work with the new meta absorber so it's hard to say exactly what fixed it. Either way the response looks much smoother than the originals, I'm impressed but I'll probably stick with the R3.

 

[peanuts]

well im not buying into some maze resonator doing anything worthwhile

 

[McFly]

Im pretty sure it actually works. But the biggest improvement would be at frequencies below 1khz instead of above imo.

 

[RayDunzl]

But meta does sound cool.

What does "meta" mean?

 

[TimVG]

What does "meta" mean?

Short for metamaterials. Materials engineered to have specific properties.

 

[ElNino]

Usually the term is also restricted to materials where the engineered properties are exotic (can't be found naturally).

 

[Deleted member 14468]

As to those who question whether or not the MAT absorber works, I'll first off say that I personally take most manufacturers' claims with a grain of salt, which is why we measure, of course. However, in this case, KEF can be checked up on through their AES paper, which was peer reviewed. Now, that's still no guarantee that it has to work exactly as advertised, but Jack Oclee-Brown and Sebastien Degraeve would be pretty foolish to put their work out there like they have if it didn't.

Here's the story about how we came to create that video. In it is a link to their AES paper: https://www.soundstageglobal.com/index.php/blogging-on-audio/926

Thanks,
Doug Schneider
SoundStage!

 

[hmt]

May be it works but for me it seems like it is solving a problem that does not really matter. Like an answere to a question nobody asked.

 

[tomtoo]

Metamatireal comes from optics. It just says if u use proper forms you can get different waveshaping than the matirial would have usualy.

 

[Deleted member 14468]

May be it works but for me it seems like it is solving a problem that does not really matter. Like an answere to a question nobody asked.

I don't think that's true at all. If you watch our video or read the article, taming resonances inside cabinets has long been a goal for many/most designers. Put drivers in a cabinet with no concern for resonances inside and see what happens to the soundwaves outside.

As Jack said in the video, usually it's with soft material, but a more targeted approach is what B&W did in the Nautilus with the tapered tubes and carried on with. It was a Laurence Dickie idea that has continued through his newer Vivid Audio speakers. The result of unchecked resonances translates into the acoustic -- and can be seen quite readily in the frequency response.

That said, KEF came up with a clever way to deal with it -- apparently VERY effectively.

Doug Schneider
SoundStage!

 

[Soniclife]

What does "meta" mean?