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KEF's New Tech is Real

Matias

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#22
Their AES published paper is attached.
 

Attachments

GXAlan

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#24
The Bowers and Wilkins drivers used in BMW cars (produced by Harman under license) use a variation of this.

1600815211643.png
 

restorer-john

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#25
well im not buying into some maze resonator doing anything worthwhile
It immediately reminded me of one of those little ball bearing plastic mazes we had as kids.
 

restorer-john

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#27
The Bowers and Wilkins drivers used in BMW cars (produced by Harman under license) use a variation of this.
It's been done for years and years. From laptop and phone speakers, to HiFi speakers. Now, they'll go on about computer optimized this and FEM that, wave some slow motion hands and dreamy looks from amazed people in a highly produced video.

All the manufacturers are all over it like a cheap suit with their own variations.

1600817220146.png
 

Matias

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#30
Last edited:

jhaider

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#32

richard12511

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#33
So, who's gonna be buying these to send to Amir?
 
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#36
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. ;)
 

hmt

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#37
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
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I don't deny this but this sounds like this Problem has never been solved without that metamaterial. Most good Speakers already deat with resonances inside their Cabinets.
 

thewas_

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#38
I don't deny this but this sounds like this Problem has never been solved without that metamaterial. Most good Speakers already deat with resonances inside their Cabinets.
The usage in this case though is for dome tweeters which have their own little closed volumes behind where some used few mineral damping and others used exponential tubes like B&W, Vivid Audio and KEF in the past.
 
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