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New KEF LS50 collection with new Metamaterial Absorption Technology (MAT) coming.

napilopez

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Thanks for the first impressions. It sounds like a worthwhile upgrade.

Are you going to measure and post the spinorama for these puppies as well?

Yep, the usual suite. Since these are coaxial, I might be able to get useful full range distortion measurements out of them too. MIght be a while until I can get to the spins though. My old stand setup doesn't really work for measuring in the new place's back yard, so I'm trying to figure that out; I got away with measuring the nest audio because they were small enough to fit on a tripod
 

Darwin

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I had the previous version LS50W, eventually found out it came with only 12month warranty for electronics for a reason. Lasted 2 years, needed both boards on both speakers replaced. Preferred the simpler setup, but have now gone back to passives. Keen to hear the new LS50 Meta though.

Ditto, plus they were missing many things like Airplay. I sold mine after two repairs and terrible service from Kef.
 

whazzup

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What is interesting here is that the LS50 meta (owing to the fame of the LS50) is one of the most recognizable consumer hifi speaker that has a very linear frequency response and consistent directivity.

It's going to be awesome fun to see subjectivist reviewers, in their future speaker reviews, trying to find 'poetic words' to describe how another speaker sounds better.
 

Steve Dallas

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First impressions after a few hours of listening. 100% subjective and I'm obviously I've already seen KEF's measurements, so that may be coloring my impressions. Grain of salt and all that.

But so far... man, these are sounding great.

The one thing that I can say with a fair bit of confidence is that the LS50 Meta sounds like a very different speaker to the original. Granted, I haven't heard the LS50 a couple of years, but from my recollection, this speaker sounds totally different. I'm not getting any hint of brightness. It sounds fuller and, dare I say it, a hair "warm" of neutral. I always thought the original passive LS50 sounded forward/brightish' but a little cold and slightly hollow. The LS50 Metas are sounding excellent at very low volumes too.

Even though KEF rates these the same as the original for bass extension, these seem surprisingly weighty. I mean, I'd still cross them with a sub, but I didn't find them lacking in bass the way I did the original. Granted, I have them quite near to the rear wall and have not tried the bungs yet.

I'm not trying to build more hype for these speakers and have tried to actively prevent myself from thinking that way. I mostly liked the originals, but I wasn't crazy about them, so I'm not exactly feeling nostalgia. The metamaterial is cool, but I don't know what impact it has on audible sound quality beyond the actual frequency response. Whatever the case, it seems pretty clear to me that KEF has made a significantly better speaker.

They also don't sound slightly recessed in the mids to me the way the R3 did. Slightly laid back, perhaps, but the R3 had a slight dullness as its worst bit of coloration.

I even think I'm enjoying them more than the Chora 806 that's my usual reference -- or perhaps they jive with the new space better. That's a pretty big deal -- there have been a few speakers that I know are technically better than the Choras that I haven't enjoyed as much, largely because of my preference for its extended wide directivity.

But the LS50 are imaging really well. It's possible their narrower-than-the-focals (I think!) directivity is helping negate the asymmetrical setup in my new place, or their directivity is just better. The vertical reflections will obviously be better controlled. They seem to be more stable about head movement/listening window than the Chora too.

I haven't even finished setting up my sound system and placement in my new place, so who knows. But to be fair, the speakers are currently just sitting on top of the Choras, so the different height might have something to do with it.

My impressions aside, thought I'd point out something interesting in the manual. I've previously complained that the R3 shows the speaker with toe in when KEF has told me the speakers are designed to be heard without toe-in and they measure better that way.

The LS50 Meta manual, however, specifically suggests using little to no toe-in, even for home theater.

View attachment 88132

So at the very least, this KEF speaker is designed to be heard off-axis. I'd like to think me complaining about it had something to do with the manual change, but I'm not that important :)

This is what we'd expect to be the optimal setup, given the on-axis diffraction in the spin but a much smoother listening window and front early reflections curve.

More impressions to follow -- should get a lot more listening time over the weekend.



Your latter impressions echo my thoughts a lot. I had already started typing my impressions before I saw your post, but as you see I thought much the same.

FWIW, I have always found my LS50s to sound best with little to no toe-in. I usually position them 12 to 16" from the front wall to leverage some boundary effect on the low end, which works well.

I would love to hear the new ones, but I think I am near the end of my LS50 experience.
 

JohnnyHonda

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I haven’t seen many reviews of the KEF LS50 Wireless ii so I thought I would chime in on my experience, especially since I have come directly from the KEF LS50 Wireless. I really enjoyed the original Wireless with pristine and clear sound, with excellent width of imaging and reasonable bass that I extended through an SVS SB3000 subwoofer through the KEF app, using their digital crossover. The imaging of the speakers was quite good, the digital time delay of the concentric speaker really doing its work. I really enjoyed the sound but it took some time to tame the high frequencies. Primarily, I angled the speakers a bit straight ahead which took advantage of their improved frequency response slightly off-axis as it relates to the high frequencies. Sometimes, I would cut the high frequencies by 0.5 db to tame the edge. The KEF app was frustrating, to say the least, and the stability was the worst part of this experience. I did enjoy the digital app to integrate the subwoofer and the Wireless, quick and seemless. The speakers would go fairly loud but compressed a bit at headbanging levels. My room is 12 x 21 x 9, not too bright or dark, with bass traps, absorption behind and to the side of the speakers and GIK diffusion/absorption panels on the back wall and on my ceiling.

I received my KEF LS50 Wireless ii’s 11 days ago and they have exceeded my good but realistic expectations. 1) The app has not caused me any problems yet....crossing my fingers but the original app was so unstable 2) The high frequencies are sooo smooth that the speaker sounds different, and better. Gone is the edge. The speakers are still clear but with a different smoothness than the sharp clarity of the original. I like clear highs but dislike the edge, so this is quite a relief. The smoothness of frequency, on-axis, off-axis is so good. 3) The extra power just gives the speakers more life and less compression, just sounds more like real instruments and voices 4) The imaging of the original was great but these are even better! There is more depth and instead of the images being as pointed, they seem to be more round with space. Even listening off-axis, the imaging is definitely better. 5) Being a Tidal user, I like the MQA compatibility.

I’ve owned Pioneer, Polk, Boston Acoustics, Rogers, electrostatic Acoustat Spectra 22s, Paradigm, Thiel 2.3, Energy Veritas. I heard many times Sanders electrostatics, B&W, Magneplanar 3.6, Martin Logan, Quad ESL 63, Vandersteen 5A, so many boutique speakers that no longer exist...I try not to listen to speakers that I can’t afford. I enjoy Stax headphones, currently L700....but these speakers are something to listen to and if you like bass, I can’t recommend high enough the SVS SB3000, I cross them over at 75hz. Maybe horn speakers for pure loudness but for everyone else, take a listen, these speakers will have you enjoy your music for many years to come. Highest recommendation for rooms of a moderate size.
 
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Kachda

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I really enjoyed the sound but it took some time to tame the high frequencies. Primarily, I angled the speakers a bit straight ahead which took advantage of their improved frequency response slightly off-axis as it relates to the high frequencies. Sometimes, I would cut the high frequencies by 0.5 db to tame the edge. The KEF app was frustrating, to say the least, and the stability was the worst part of this experience. I did enjoy the digital app to integrate the subwoofer and the Wireless, quick and seemless. The speakers would go fairly loud but compressed a bit at headbanging levels. My room is 12 x 21 x 9, not too bright or dark, with bass traps, absorption behind and to the side of the speakers and GIK diffusion/absorption panels on the back wall and on my ceiling.
.

I think I know exactly what you mean by this. I have the KEF R3 and on certain songs it was painful. I had an amp with tone controls and treble would always be at -3 and even then I would feel some songs jarring (God only knows by Beach Boys was always good to set of ear pain).

I recently switched to a Minidsp SHD and a March Audio NC502 based amp (just got it in a couple of days ago). I don't know if it's the Dirac or the more powerful amplifier, but the harshness is now gone completely. I could listen to songs for hours yesterday with no fatigue. (Thought I haven't dared queue up God only knows yet :). )

So along with their new meta material, they may have beefed up the amp or improved the DSP as well to remove that sizzle from the sound.
 

JohnnyHonda

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Funny you should mention The Beach Boys as that is my favorite song from them. I think the meta material really is absorbing the back wave and cleaning up the mids to treble and you can also see that the response is much smoother in the new Wireless ii. It feels so much more relaxing, like few speakers that I’ve heard. My Stax headphones have a similar lack of distortion and ease of sound. I hope your new dsp and amp are doing the same for you (and continues to do so).
 

thewas

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(very good) NRC measurements of the new passive LS50 Meta
https://www.soundstagenetwork.com/i...ef-ls50-meta-loudspeakers&catid=77&Itemid=153
KEF seems to have successfully corrected the FR problems of the first passive one
https://www.soundstagenetwork.com/i...&catid=77:loudspeaker-measurements&Itemid=153
rest looks as excepted very similar, "unfortunately" already the distortion measurements of the old tweeter were beyond the plot scale so we cant see the differences of the new one with the META absorption material, also as per NRC standard unfortunately no decay spectrum measurements.
 

aarons915

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(very good) NRC measurements of the new passive LS50 Meta
https://www.soundstagenetwork.com/i...ef-ls50-meta-loudspeakers&catid=77&Itemid=153
KEF seems to have successfully corrected the FR problems of the first passive one
https://www.soundstagenetwork.com/i...&catid=77:loudspeaker-measurements&Itemid=153
rest looks as excepted very similar, "unfortunately" already the distortion measurements of the old tweeter were beyond the plot scale so we cant see the differences of the new one with the META absorption material, also as per NRC standard unfortunately no decay spectrum measurements.

Very nice indeed and you can see it matches very well with KEF's own measurements in the whitepaper, meaning they could be used to make them even better.
 

Joaquinín

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I am not technically educated, but isn´t this noticeable higher distortion that the one from Neumann´s Kh-120? May be the difference is due to this second chart not including noise, just THD?
 

ElNino

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I am not technically educated, but isn´t this noticeable higher distortion that the one from Neumann´s Kh-120? May be the difference is due to this second chart not including noise, just THD?

On the bass end, yes. The NRC measurements don't provide enough information to compare the rest of the spectrum.
 

thewas

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Yes, on bass max SPL the KH120 is on a different league (I have them both).
We shouldn't forget that the LS50 woofer has also quite less surface due to the tweeter and its waveguide inside.
 
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Xyrium

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Here are those measurements with proper scaling, using the scientifically-determined best spinorama color-scheme:

LS50 Meta:

View attachment 84343

LS50 Wireless 2:

View attachment 84344

For reference, here's how the listening window and ER, the two most important curves, imo, compare to Amir's spin for the Genelec 8341:

So very much comparable. Eagle-eyed observes will note the Genelec appears to have ever so slightly better directivity while the LS50W II has an ever so slightly smoother listening window. Probably at the point of being negligible considering the different measurement sources. Though I'm curious how the small woofer will handle higher SPLs, it seems the LS50W will sound excellent in its comfortable range.

EDIT: Also note that the LS50 Meta and Wireless II have absolutely identical DI curves, so getting the passive version to sound like the active one should be a matter of basic EQ. Basically just needs a 1-2dB lift between 2k and 4k and a slight pulling down around the mids.

Here's how the two on-axis graphs compare and the difference between them(offset by 60 dB for display purposes):

So the difference is quite subtle overall, though of course the LS50W II has some built in extra EQ via the app.

Funny, when I measure my cheapo Dyn Emit 10s, they have that same ugly hump in the presence region. Creating that fake "window into the recording" as so many like to claim.

That said, I'm infinitely interested in the LS50W....or any of the latest crop of powered, DSP-tweaked monitors that can produce 40Hz at -3dB with a 5 in. woofer, if the distortion is managed as well. As it stands, it appears that the Genelec 8030 still outperforms these, at a similar price.

The marketing nonsense with unobtanium materials is truly a turn off however. I wish they didn't have to resort to such practices. Just say you stuffed the box with different/more polyester or something.....poly isn't naturally occurring.... Sorry, ugly marketing makes me grouchy. I'll still buy 'em if they measure well, and I won't return them if they sound good. :)
 

Sancus

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The measurement of LS50 I'd be most curious to see is an IMD comparison between it and a good non-coaxial. Mostly because as I understand it 2-way coaxials usually have bad IMD, and Kef's have been called out for that elsewhere. Unfortunately the only source I'm aware of that produces consistent IMD measurements is S&R. And since I haven't seen any real standard for IMD measurements I don't know that you can even compare across sources.
 

napilopez

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Funny, when I measure my cheapo Dyn Emit 10s, they have that same ugly hump in the presence region. Creating that fake "window into the recording" as so many like to claim.

That said, I'm infinitely interested in the LS50W....or any of the latest crop of powered, DSP-tweaked monitors that can produce 40Hz at -3dB with a 5 in. woofer, if the distortion is managed as well. As it stands, it appears that the Genelec 8030 still outperforms these, at a similar price.

The marketing nonsense with unobtanium materials is truly a turn off however. I wish they didn't have to resort to such practices. Just say you stuffed the box with different/more polyester or something.....poly isn't naturally occurring.... Sorry, ugly marketing makes me grouchy. I'll still buy 'em if they measure well, and I won't return them if they sound good. :)

Well, ignoring the nigh-irrelevant on-axis measurement, performance looks extremely similar to the genelec while arguably looking nicer and being more room independent due to vertical directivity. Imo they're completely comparable, with the LS50 being a bit better in the directivity department and the 8030C (probably) being able to get louder and coming with integrated amplification. (but requiring more cables). The Meta is also a hair warm of neutral. Pick your poison!

LS50 Meta(Blue) vs 8030C(Red), comparing the two most important curves, LW and ER. I took the liberty of splicing the bass from the on-axis curve for the Metas LW.

LS50 Meta vs 8030C.png


If anything, it's pretty notable the meta performs so well sans DSP. Based on the spin alone and knowing the LS50 is coaxial, I'd probably pick it over the genelec, at least if pairing with a sub, due to the lack of vertical lobing.

We'll also have to wait until we see some more distortion metrics, but I think KEF is justified in its marketing this time around when they share the data for you to assess. The metamaterial is clearly doing exactly what KEF says it does. As noted in another post, KEF set out to achieve something with the metamaterial in a way that it hadn't quite been done before, and by all indications, they appear to have done it.
 

Xyrium

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Hmm, good point(s) on it being non-DSP!

I think the whole metamaterial and then naming it such really irked me enough to nitpick! If you consider that metamaterial is just a term fairly synonymous with "synthetic" from what I can discern.

Edit: Would still love to see the LS50W measured here

Edit 2: I dig the watermark! Amir should consider doing that to his graphs!

Edit 3: Amir does sign his charts...geez....
 
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napilopez

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Hmm, good point(s) on it being non-DSP!

I think the whole metamaterial and then naming it such really irked me enough to nitpick! If you consider that metamaterial is just a term fairly synonymous with "synthetic" from what I can discern.

Edit: Would still love to see the LS50W measured here

Edit 2: I dig the watermark! Amir should consider doing that to his graphs!

KEF didn't come up with that name though, I'd been heading about metamaterials for years =] But yes, the term does have a certain fancifulness to it.
 

mhardy6647

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it takes disruptive, innovative nanotechnology to make metamaterials.
:facepalm:

1605271695318.png


Now -- mind you -- I love jargon. It's tailor-made to separate the insiders from the outsiders.
But I get pretty tired of jargon for its own sake.

A long time favorite of mine -- someone had a decaffeinated coffee or tea product which they touted as being decaffeinated using Nature's own effervesence. In reality-speak, the product was decaffeinated using supercritical fluid extraction (which uses carbon dioxide at very high pressure to act as a good nonpolar solvent, instead of nastier organic solvents traditionally used). It was pretty new technology at the time, and it is cool and a Good Thing and all... but... jeepers.

For those of you (us) who do -- or have done -- time in the for-profit world... here's a handy tool.
I think we were talking about this elsewhere on this site recently(?) I know we were talkin' about it at another hifi site recently.
https://www.atrixnet.com/bs-generator.html

1605272033804.png


Now, if you'll excuse me, I have to go and ... umm... <click> objectively optimize user-centric supply chains.
I'll be finished in time for lunch!
:cool:
 
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