KEF LS50

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In my opinion, the LS50 is an insane value at $1500. JA gave this speaker a class A rating. I can't believe that KEF is allowing that transducer to be used in such a way. Most companies would never allow it to happen.. They would use it only in their flagship. Thanks Jack. I'm pretty sure you had something to do with it..I'm saving up for it starting right now.
 
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ra7

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Joined 2009
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Be very careful about JA's measurements on Stereophile. Read the title of the on-axis measurement. The key words are, "...averaged across 30° horizontal window..." and then look at the off-axis measurements. The off-axis shows a narrowing response, which you'd expect from a tweeter. But then how come the 30 degree horizontal window response is flat? The only way it will be flat is if the on-axis has a rising response.

Then look at the in-room measurement. That is not a well-balanced speaker. It should follow a Bruel-Kjaer type of curve, where its flat between 100-500 Hz and then it's a continuous falling response. This LS50 will sound bright, hyper detailed at first, typical hi-fi sound, fatiguing in the long run.
 
Be very careful about JA's measurements on Stereophile. Read the title of the on-axis measurement. The key words are, "...averaged across 30° horizontal window..." and then look at the off-axis measurements. The off-axis shows a narrowing response, which you'd expect from a tweeter. But then how come the 30 degree horizontal window response is flat? The only way it will be flat is if the on-axis has a rising response.

Then look at the in-room measurement. That is not a well-balanced speaker. It should follow a Bruel-Kjaer type of curve, where its flat between 100-500 Hz and then it's a continuous falling response. This LS50 will sound bright, hyper detailed at first, typical hi-fi sound, fatiguing in the long run.

Here is the same driver in the KEF R500 from 500hz & up. True anechoic measurements..
NRC Measurements: KEF R500
 
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In my opinion, the LS50 is an insane value at $1500. JA gave this speaker a class A rating. I can't believe that KEF is allowing that transducer to be used in such a way. Most companies would never allow it to happen.. They would use it only in their flagship. Thanks Jack. I'm pretty sure you had something to do with it..I'm saving up for it starting right now.

I don't think these are an insane value when you figure in the cost of materials.
You might think so based on performance, but I like to look at the whole package.....design, materials, labor and performance.
Magnepan MMG's are an insane value, not these.
 

ra7

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Joined 2009
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Hmm... those are better looking measurements... The woofer is beaming by the time the tweeter comes in and there is a broad depression between 1 kHz and 3 kHz. Not super linear, but not bad.

Agree with Melo. They are okay at $1500. You'd need subs for sure. Can do much better with diy.
 
Hmm... those are better looking measurements... The woofer is beaming by the time the tweeter comes in and there is a broad depression between 1 kHz and 3 kHz. Not super linear, but not bad.

Agree with Melo. They are okay at $1500. You'd need subs for sure. Can do much better with diy.

That transducer is reason behind my thinking. It's the same one used in the blade. It is also the culmination of millions of dollars(Pounds?) worth of research in concentric driver technology. It is arguably the most advanced driver ever made. You also can't clone it in any way with DIY.
 

Here is a guy who I assume is sourcing his KEF drive units from the speaker exchange(You can see the question I asked him back in march). He's based in they same city. I wonder how many they have left in stock. I also wonder why KEF is letting him use them in a commercial design. He and KEF were both exhibiting at the Newport show. I must say, his speaker sounded very good..
http://www.stereophile.com/content/soundfield-audio-0
 
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That transducer is reason behind my thinking. It's the same one used in the blade. It is also the culmination of millions of dollars(Pounds?) worth of research in concentric driver technology. It is arguably the most advanced driver ever made. You also can't clone it in any way with DIY.

Well, sure they spent a lot on research for there drivers but that's over many years and a lot of sales. Wording like this make it sound like this one driver cost millions in research!
This is just the next step for the uni-q drivers.
I had some uni-q bookshelves and they cost 250, I'm sure at that point they spent 800,000 bucks according to the million dollar reasoning.
Now just because these new ones improve on those surely doesn't justify the huge price difference for slightly more costly materials.
I mean, this is a case of charging the most for the least amount of materials, just because it performs great shouldn't justify the cost. The designing team doesn't see that extra loot.
Great designs should only be good for a brand getting respect and greater sales based on competitive prices for the amount of materials and labor.
Well, that's how I think about it, but I would make a poor capitalist :p
 
Well, sure they spent a lot on research for there drivers but that's over many years and a lot of sales. Wording like this make it sound like this one driver cost millions in research!
This is just the next step for the uni-q drivers.
I had some uni-q bookshelves and they cost 250, I'm sure at that point they spent 800,000 bucks according to the million dollar reasoning.
Now just because these new ones improve on those surely doesn't justify the huge price difference for slightly more costly materials.
I mean, this is a case of charging the most for the least amount of materials, just because it performs great shouldn't justify the cost. The designing team doesn't see that extra loot.
Great designs should only be good for a brand getting respect and greater sales based on competitive prices for the amount of materials and labor.
Well, that's how I think about it, but I would make a poor capitalist :p

The Uni-Q has been in a constant state of refinement for what? 30 years? They are never satisfied. The design just keeps getting better and better and better.. Look at the 95 db THD graphs from the CNC. They are among the best I've ever seen from 500 hz(crossover point) & up.. Markedly better than the previous generation that Krutke tested..
 
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I don't think these are an insane value when you figure in the cost of materials.
You might think so based on performance, but I like to look at the whole package.....design, materials, labor and performance.
Magnepan MMG's are an insane value, not these.

Are these the same MMG's you were talking about being an insane value? Heh Heh..
Magnepan MMG Speaker System Measurements | Home Theater
"Before you go into shock.."
To me, it's all about performance. I don't care if it's concrete or cardboard..
I believe the lowest priced class A speaker in Stereophile is $15,000. Yes, ten times less than that is an insane value.
 
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Are these the same MMG's you were talking about being an insane value? Heh Heh..
Magnepan MMG Speaker System Measurements | Home Theater
"Before you go into shock.."
To me, it's all about performance. I don't care if it's concrete or cardboard..
I believe the lowest priced class A speaker in Stereophile is $15,000. Yes, ten times less than that is an insane value.

Wrong ones.
Those are the mmg-w.
You go ahead and save up. Ill continue to make my own.
Maybe this thread should be moved to the review section. Oh wait........we don't have one.
:rolleyes:
 
That transducer is reason behind my thinking. It's the same one used in the blade.

No. The Blade driver is dedicated mid (thin suspension, not Z-surround). Also, I think the Blade has a neo-based motor.

I must say, his speaker sounded very good..
Soundfield Audio | Stereophile.com

I had the Soundfield Audio Monitor 1's in my loft, and thought them excellent. See here for more.

I didn't buy them because the amps would have been visible to someone entering my living room, and I didn't like that.
 
KEF LS50 - What Hi-Fi? Awards - Product of the Year 2012 - Stereo Speakers - YouTube

Keep in mind that this second video was not meant for the DIY set(Obviously). A little hard to watch.. Does give some good insight into construction methods that the diy community could use though..
LS50 Ultimate Mini Monitor - KEF 50th Anniversary - YouTube

A flexible port???
ooooooweee what's up with dat? What's up with dat.

Hmmmm, now we have something to talk about.
I never do BR's but it's interesting none the less.
 
No. The Blade driver is dedicated mid (thin suspension, not Z-surround). Also, I think the Blade has a neo-based motor.



I had the Soundfield Audio Monitor 1's in my loft, and thought them excellent. See here for more.

I didn't buy them because the amps would have been visible to someone entering my living room, and I didn't like that.

Thanks for pointing that out about the blade. My bad..

Also, thanks for the Soundfield link.
 
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