• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

KEF's New Tech is Real

Joined
Aug 17, 2020
Messages
20
Likes
11
#61

Zvu

Active Member
Joined
May 1, 2020
Messages
122
Likes
95
Location
Serbia
#62
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.
Umro sam od smjeha kada sam procitao visokotonac i bas na dijagramu. ;)
Actually, I'd say "smeha" but "smjeha" is also Ok :)

More about that you'll find here:

http://www.htguide.com/forum/showthread.php?44315-Measurements-of-Kef-LS50

There is final schematic for both left and right loudspeaker with gated measurements (this time in room, not at a basketball court).
 
Joined
Aug 17, 2020
Messages
20
Likes
11
#63
Actually, I'd say "smeha" but "smjeha" is also Ok :)

More about that you'll find here:

http://www.htguide.com/forum/showthread.php?44315-Measurements-of-Kef-LS50

There is final schematic for both left and right loudspeaker with gated measurements (this time in room, not at a basketball court).
Cao Zvu,

Kuzim nema problema. Ja sam iz stare Jugoslavije a taj dio je sada Hrvatska. Hleb, kruh ti znas sta ja mislim. ;)
Are you the guy who worked on the KEF R300 crossover? I have some KEF gear (R500, LS50W, R200C, and R400B) and always interested to learn more.
 

Matias

Major Contributor
Forum Donor
Joined
Jan 1, 2019
Messages
1,235
Likes
1,598
Location
São Paulo, Brazil
#64

Matias

Major Contributor
Forum Donor
Joined
Jan 1, 2019
Messages
1,235
Likes
1,598
Location
São Paulo, Brazil
#66
Here is everyone's favorite youtuber review.

 

phoenixdogfan

Addicted to Fun and Learning
Joined
Nov 6, 2018
Messages
735
Likes
636
#67
It's the prefix in the ancient Greek language for "beyond". For example the Greeks invented Metaphysics, which is the branch of speculative thought/philosophy through which they sought to explain a reality which they believed beyond was beyond the ken of physics, in other word, realities which they believed were beyond the abilities of their physical scientists to explain. So in this context, which is a marketing one, a "meta" material means some kind of material which transcends what ordinary material science has to date been able to accomplish.
 

AnalogSteph

Addicted to Fun and Learning
Joined
Nov 6, 2018
Messages
730
Likes
523
Location
.de
#69
And the white paper of their new LS50 models incorporating those is now also online
https://us.kef.com/pub/media/wysiwyg/ls50/20-KEF-LS50-Collection-WhitePapers.pdf
Both the woofer and the tweeter (!) feature copper shorting rings now. Given that both parts featured dominant 3rd harmonic at the 90 dB level in Erin's testing, that should be a welcome improvement. It does seem to have helped out the woofer at the very least - I bet if you'd look at the individual harmonics or IMD/multitone, the difference may turn out to be larger than the up to ~10 dB reduction in THD would suggest.

Should somebody be able to spare one of these, I would certainly like to see @hardisj test the new drive units as well.
 

bunkbail

Senior Member
Forum Donor
Joined
Feb 27, 2018
Messages
428
Likes
456
#70
Ej, sve je to moj jezik - šta god par fanatika na vlasti pričalo :)

Yup, i'm the villain who destroyed few factory made Kef crossovers. The more of it i destroy, the better it plays :)
Now do it with the KEF LS50 Meta as well:p.
 

Soniclife

Major Contributor
Forum Donor
Joined
Apr 13, 2017
Messages
3,292
Likes
3,284
Location
UK
#72
It's the prefix in the ancient Greek language for "beyond". For example the Greeks invented Metaphysics, which is the branch of speculative thought/philosophy through which they sought to explain a reality which they believed beyond was beyond the ken of physics, in other word, realities which they believed were beyond the abilities of their physical scientists to explain. So in this context, which is a marketing one, a "meta" material means some kind of material which transcends what ordinary material science has to date been able to accomplish.
I cannot tell if you are being incredibly meta about the term meta, or you are unaware of the other use of the word, that I was alluding to, that turns up in memes often.
 
Joined
Jun 23, 2019
Messages
80
Likes
76
#74
What are we looking at for active blades 3-4 amp packs plus dsp dac, thats a lot to package in a sculptural form.

Also ts not like kef are a mixed skill company, they do speakers, not amps, digital, software.

Id love to see them though
 
Joined
Aug 2, 2020
Messages
80
Likes
50
#75
Cao Zvu,

Kuzim nema problema. Ja sam iz stare Jugoslavije a taj dio je sada Hrvatska. Hleb, kruh ti znas sta ja mislim. ;)
Are you the guy who worked on the KEF R300 crossover? I have some KEF gear (R500, LS50W, R200C, and R400B) and always interested to learn more.
Ej, sve je to moj jezik - šta god par fanatika na vlasti pričalo :)

Yup, i'm the villain who destroyed few factory made Kef crossovers. The more of it i destroy, the better it plays :)
Pa gdje ste svi?

The price for a new pair of passive will be lower than it was for an original pair. I bought mine so cheap (completely new - closed box), that I'm really tempted to switch. Even today I might get the same price I payed when I bought them.
 

firedog

Active Member
Joined
Jun 19, 2016
Messages
201
Likes
242
#76
Very impressive! Doesn't seem like fluff to me.

KEF also essentially says that active speakers is an inherently superior design. Which makes me ask why there is still no active version of the blade, for example...
Because the market for Blades is for audiophiles who don't want actives. People for whom the hobby includes playing with boxes, etc.
 

firedog

Active Member
Joined
Jun 19, 2016
Messages
201
Likes
242
#77
Also, why all that pesky streaming and wireless stuff in the LS50W inflating the cost. There's a market for amplification and crossover-only active LS50 in the studio monitor market IMO, competing with Neumann and Genelec.
I think they know exactly what they are doing with the wireless. It's directed squarely at the consumer/lifestyle/audiophile markets. The previous version was extremely successful across all those markets, doubtless this one will be, too.
 

Soniclife

Major Contributor
Forum Donor
Joined
Apr 13, 2017
Messages
3,292
Likes
3,284
Location
UK
#78
Because the market for Blades is for audiophiles who don't want actives. People for whom the hobby includes playing with boxes, etc.
Nothing creates lots more boxes to play with than external active, look at the huge numbers of boxes that are required for active Linn / Naim systems. Maybe this is too many boxes these days.
 

lashto

Addicted to Fun and Learning
Forum Donor
Joined
Mar 8, 2019
Messages
535
Likes
240
#79
not exactly new tech (~2017) and also not Kef's technology. Kef's speakers might be the first commercial application, though. Nevertheless, pretty cool stuff.
A few bits from the AMG site & Darko's article that I find most interesting:
Darko said:
AMG has reportedly built an anechoic chamber prototype whose walls are lined only with 3-4 inch thick metamaterials
3-4" thickness should be ok for most rooms. And those mazes look kinda cool, might have a good WAF too.
Could also be perfect if you have a boiler room or other noisy house installations. Or for a dedicated cinema room. Assuming of course that they do not cost more than the house.

AMG said:
Metamaterial is not in itself a new material - we shape solids to form various geometries such as tiny chambers or channels for different resonances... MAT is a highly complex maze-like structure, where each of the intricate channels efficiently absorbs a range of specific frequencies. When combined, the channels act as an acoustic black hole, absorbing 99% of the unwanted sound.
...
We can maximise the absorption of a given space on specific targeted frequencies ... Our acoustic metamterials solution enables us to effectively provide customized noise control.
IIUC, it should be possible to build user-customizable absorber panels. I.e. one can adapt the panels to his own room conditions/frequencies by changing the 'maze' structure.
 
Last edited:

ahofer

Addicted to Fun and Learning
Forum Donor
Joined
Jun 3, 2019
Messages
683
Likes
1,037
Location
New York City
#80
Top Bottom