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LS50 vs LS50 Meta Comparison

HarmonicTHD

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Could someone check please. I remotely remember that the above mentioned UniQ are not identical, at least not with regard to their motor units. I might remember incorrectly though.
 

phoenixdogfan

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Could someone check please. I remotely remember that the above mentioned UniQ are not identical, at least not with regard to their motor units. I might remember incorrectly though.
If you are talking about LS 50 vs LS 50 Meta, different generations of Uni-Q, so therefore different units. The Uni-Q in the Blades and Reference Models, both Meta and OG, are also different premium units with better magnets, etc.

So different drivers among models as well as different generations used in the Meta models.
 

ROOSKIE

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To piggyback off this.... a poor man's blade/reference

I'm building a woofer/sub module for the LS50M. 25" high, with a 12" rs315hf per unit, and a minidsp 2x4hd for crossover duty. The idea being that I can crossover as high as needed, likely between 150 to 300hz 4th order. I can play with that as needed.

The only concern I have is how low I can safely mount the woofer on the baffle to alleviate some floor bounce cancellation, but still remain high enough to crossover seamlessly for 2-3m sitting distances. I'm hoping this will free up some spl and make the whole experience full range.

This begs the question, based on distortion data, what is the ideal place to crossover the LS50M into a 3 way without messing with the point source effect.
I have made a number of 2 ways into 3 ways this way.
1/4 wavelength is the typical distances not to exceed, though in the bass there is likely more leeway.
You should be able to place the drivers at the floor and depending on the exact frequency place them closer to the side walls to help alleviate SBIR.

Make sure all distance from boundaries are different.(SBIR)

I sometimes place the monitors on the woofers and other times have placed the woofers closer to the room boundaries and just time aligned them. In my situation crossing at about 150hrz this is no issue.

I suspect near zero benefit to crossing the LS50 META above 150-180hrz*. Obviously test your woofers to ensure they plan there with lower distortion that the LS50 Meta. Some woofers are already starting to 'break-up' and at 200-300hrz and will actually emit higher distortion levels than a high quality mid woofer. Measure them.

My LS50's measure with very low HD distortion above 150 hrz. By 165hrz 3rd order is below 0.2% and 2nd below 1%. 3rd order never rises above 0.2% from 150-20k and 2nd is at or below 0.5% for most of the range from 200-20k.
Below 130hrz Harmonic Distortion rises fairly rapidly and by 90hrz these are hurting.
Small woofers moving at higher excursions can create doppler distortion as well as the IMD issues so a bigger woofer will help there below 90hrz as well along with the easy to measure HD I mention above.

*I plan to cross them in my set-up at 125hrz LR4 to 2 woofers, since they will be 6db down by 125hrz I suspect that will be a great point. Higher would lead to a bit lowered measured distortions but likely zero audible gains. 2% 2nd order distortion at 100 where the LS50 will be down by 8db is hardly going to audible. Woofer excursions are not likely an issue anymore with these numbers either.

*EDIT* published my HD 'specs' without stating they are at [email protected] Can really only be compared with other tests taking with my exact set-up. To summarize the LS50 woofer is exceptional for such a small driver with a great tweeter. That said it is a small driver and higher SPL warrants a 100+ or even better 125+ X-over to minimize potential audible issues.
 
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ROOSKIE

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Very different details with obviously a baseline of similarity

Reference 1 Meta
1666717319496.png


LS50 Meta
1666717377766.png
 
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muad

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I have made a number of 2 ways into 3 ways this way.
1/4 wavelength is the typical distances not to exceed, though in the bass there is likely more leeway.
You should be able to place the drivers at the floor and depending on the exact frequency place them closer to the side walls to help alleviate SBIR.

Make sure all distance from boundaries are different.(SBIR)

I sometimes place the monitors on the woofers and other times have placed the woofers closer to the room boundaries and just time aligned them. In my situation crossing at about 150hrz this is no issue.

I suspect near zero benefit to crossing the LS50 META above 150-180hrz*. Obviously test your woofers to ensure they plan there with lower distortion that the LS50 Meta. Some woofers are already starting to 'break-up' and at 200-300hrz and will actually emit higher distortion levels than a high quality mid woofer. Measure them.

My LS50's measure with very low HD distortion above 150 hrz. By 165hrz 3rd order is below 0.2% and 2nd below 1%. 3rd order never rises above 0.2% from 150-20k and 2nd is at or below 0.5% for most of the range from 200-20k.
Below 130hrz Harmonic Distortion rises fairly rapidly and by 90hrz these are hurting.
Small woofers moving at higher excursions can create doppler distortion as well as the IMD issues so a bigger woofer will help there below 90hrz as well along with the easy to measure HD I mention above.

*I plan to cross them in my set-up at 125hrz LR4 to 2 woofers, since they will be 6db down by 125hrz I suspect that will be a great point. Higher would lead to a bit lowered measured distortions but likely zero audible gains. 2% 2nd order distortion at 100 where the LS50 will be down by 8db is hardly going to audible. Woofer excursions are not likely an issue anymore with these numbers either.
What spl were your distortion measurements performed at? The rs315hf has very low distortion and really excellent breakup behaviour for a 12" subwoofer. I chose it for to give me the option to cross as high as necessary.

Would crossing up to 200hz be acceptable with the woofer close to the ground? 1/4 wave length at 200hz is around 16inches, so it would exceed the 1/4 wavelength difference. But if ls50m distortion at 96db at 150hz is that low... Maybe I don't need to cross at 200hz.

I really don't think I have space for seperate subs and mains on stands. I was just going to make the sub/woofer module double as stands. I might just design it so I can flip it over to try to try the woofer high vs low.

Edit: you being up a good point about the LS50M being down 6db at the crossover point. So 150hz might be good enough for home theater.
 
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HarmonicTHD

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If you are talking about LS 50 vs LS 50 Meta, different generations of Uni-Q, so therefore different units. The Uni-Q in the Blades and Reference Models, both Meta and OG, are also different premium units with better magnets, etc.

So different drivers among models as well as different generations used in the Meta models.
Yes. Thanks. So I indeed remembered correctly.
 

HarmonicTHD

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What spl were your distortion measurements performed at? The rs315hf has very low distortion and really excellent breakup behaviour for a 12" subwoofer. I chose it for to give me the option to cross as high as necessary.

Would crossing up to 200hz be acceptable with the woofer close to the ground? 1/4 wave length at 200hz is around 16inches, so it would exceed the 1/4 wavelength difference. But if ls50m distortion at 96db at 150hz is that low... Maybe I don't need to cross at 200hz.

I really don't think I have space for seperate subs and mains on stands. I was just going to make the sub/woofer module double as stands. I might just design it so I can flip it over to try to try the woofer high vs low.

Edit: you being up a good point about the LS50M being down 6db at the crossover point. So 150hz might be good enough for home theater.
I would not consider distortion at 96dB at 150Hz low. The speaker works great up to 86dB, but beyond physics simply takes its toll.

1666721962239.png


Yes you most likely need to crossover around 150 to 200 but it will all be a compromise as the subs would still have to work at around 300 to 400Hz assuming 12 to 24dB/Oct filters. So check your sub distortions at those frequencies. If it works out ok, than definitely two subs closely located to the LS50 themselves which in turn takes away the advantage of subs as you are now limited to address room nodes by strategic sub placement. As I said all a big compromise imho and far away from a poor man’s Blade.
 

Cote Dazur

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they sounded exactly like they measured
it is no contest that the Meta are the more neutral speaker and would be preferred by most people
Do you mean that you conducted a ABX testing and people taking part in the test actually preferred the Meta?
Or there was no abx comparison and those comments are just your biased opinion?
 

muad

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I would not consider distortion at 96dB at 150Hz low. The speaker works great up to 86dB, but beyond physics simply takes its toll.





View attachment 239402

Yes you most likely need to crossover around 150 to 200 but it will all be a compromise as the subs would still have to work at around 300 to 400Hz assuming 12 to 24dB/Oct filters. So check your sub distortions at those frequencies. If it works out ok, than definitely two subs closely located to the LS50 themselves which in turn takes away the advantage of subs as you are now limited to address room nodes by strategic sub placement. As I said all a big compromise imho and far away from a poor man’s Blade.
If you lower your expectations.. a Logitech speaker can be a poor man's blade ;)

To be fair, any speakers in any room is a compromise. It's up to the end user to decide on where their priorities lie, and to design their system around it. Take a look at the $30000 speaker recommendation thread that's going on as an example...

For my space and my needs, having the subs under the mains works for me. I don't listen to music glued to one seat, and I enjoy music from all over my untreated open concept living space. Yes it's not the ideal sub position but floor space is a commodity.

No I don't think they will be the same as blades, but will get me most of the way there. SPL will be limited, but if I wanted concert level spl, I would have chosen different speakers.

All I asked for was where the ideal crossover is to minimize imd, and ihd, without disrupting the point source effect. I love the meta and just want to optimize them to let them reach their potential.
 

HarmonicTHD

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If you lower your expectations.. a Logitech speaker can be a poor man's blade ;)

To be fair, any speakers in any room is a compromise. It's up to the end user to decide on where their priorities lie, and to design their system around it. Take a look at the $30000 speaker recommendation thread that's going on as an example...

For my space and my needs, having the subs under the mains works for me. I don't listen to music glued to one seat, and I enjoy music from all over my untreated open concept living space. Yes it's not the ideal sub position but floor space is a commodity.

No I don't think they will be the same as blades, but will get me most of the way there. SPL will be limited, but if I wanted concert level spl, I would have chosen different speakers.

All I asked for was where the ideal crossover is to minimize imd, and ihd, without disrupting the point source effect. I love the meta and just want to optimize them to let them reach their potential.
Sure. And I love Kef and have myself some. I hope I was able to point out the few aspects to choose the best option in crossover etc for your application.
 

phoenixdogfan

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I would not consider distortion at 96dB at 150Hz low. The speaker works great up to 86dB, but beyond physics simply takes its toll.

View attachment 239402

Yes you most likely need to crossover around 150 to 200 but it will all be a compromise as the subs would still have to work at around 300 to 400Hz assuming 12 to 24dB/Oct filters. So check your sub distortions at those frequencies. If it works out ok, than definitely two subs closely located to the LS50 themselves which in turn takes away the advantage of subs as you are now limited to address room nodes by strategic sub placement. As I said all a big compromise imho and far away from a poor man’s Blade.
True, a pair of Metas plus 12" subs crossed over at 150hz with a L-R filter, with the subs place around 2 ft away from the mains (1/4 wavelength), and using Dirac Live to tame what can be tamed won't be as good as a pair of Blade Metas (especially at higher volumes, but who listens at 90db+ consistently)? But for most people they will be one of the very best systems they could have--especially in a smaller listening space.

And of course without external subs, the Blades will also lack the capability of taming room nodes, and no one says you could not add a third stragegically placed small sub to the LS50 Meta + subs to tame a room node or two if that proves to be a major problem.

Ultimately, the biggest issue with the Meta set up is it might on occasion seem slightly strained (distorted) and less effortless than the Blades, particularly in the midbass/lower midrange during peaks (90+ db). Undoubtedly means they won't sound as big as the Blades, but what does?

Considering a LS 50 Meta + subs +Dirac can be obtained for between $4-5k, maybe less, that seems like a shockingly small performance compromise to me.
 
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ROOSKIE

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What spl were your distortion measurements performed at? The rs315hf has very low distortion and really excellent breakup behaviour for a 12" subwoofer. I chose it for to give me the option to cross as high as necessary.

Would crossing up to 200hz be acceptable with the woofer close to the ground? 1/4 wave length at 200hz is around 16inches, so it would exceed the 1/4 wavelength difference. But if ls50m distortion at 96db at 150hz is that low... Maybe I don't need to cross at 200hz.

I really don't think I have space for seperate subs and mains on stands. I was just going to make the sub/woofer module double as stands. I might just design it so I can flip it over to try to try the woofer high vs low.

Edit: you being up a good point about the LS50M being down 6db at the crossover point. So 150hz might be good enough for home theater.
Sorry I forgot to post that part of my spec.
90db @ 1meter

@90 @ 2meters([email protected]) the 2nd order is about exactly double and the 3rd creeps up a bit but is still extremely well controlled above 150hrz.

Plus factor in distortion from my $100 mic, UMIK calibrated. There is no way that mic is not adding it's some amount of it's own issues even if minor, so the LS50 is lower that what I have.

HD distortion is most likely not the real issue, IMD and Doppler from large excursions would be but a 125+ LR4 crossover very likely takes complete care of that (within the potential of these drivers) and you can try LR8 but I have had much better success with a larger overlap with my additional woofers.
 

Tom C

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To piggyback off this.... a poor man's blade/reference

I'm building a woofer/sub module for the LS50M. 25" high, with a 12" rs315hf per unit, and a minidsp 2x4hd for crossover duty. The idea being that I can crossover as high as needed, likely between 150 to 300hz 4th order. I can play with that as needed.

The only concern I have is how low I can safely mount the woofer on the baffle to alleviate some floor bounce cancellation, but still remain high enough to crossover seamlessly for 2-3m sitting distances. I'm hoping this will free up some spl and make the whole experience full range.

This begs the question, based on distortion data, what is the ideal place to crossover the LS50M into a 3 way without messing with the point source effect.
This should be outstanding.
 

pablolie

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My experience was that I prefer the sound of my original LS50 (I love the racing red special edition) -crossed over at a low 70Hz with a single sub- to the Reference 1s in my room. The latter needed no sub for me, but were still too "boomy" in some ways when positioned where I need my stereo speakers to be.

Sub positioning and xover was optimized with a room correction tool.

To me the fundamental issue is that if the <80Hz frequencies are integrated into the speaker, positioning gets more challenging. And if your room correction dials down the main speakers' bass, it means you paid for performance potential you're not using.

I intended to keep experimenting, then decided I'd move to a new place... but now stopped that initiative to await house market developments.

So following this discussion with interest.
 

Doodski

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To me the fundamental issue is that if the <80Hz frequencies are integrated into the speaker, positioning gets more challenging. And if your room correction dials down the main speakers' bass, it means you paid for performance potential you're not using.
How many good speakers don't go <80Hz? I usually cross over a active sub @~80Hz and avoid all that fatty booming sounding bass when the speakers are merged with the subs @ too high a freq. There are peeps using 120Hz and are recommending that too. But 80Hz and below is not paying for potential that is wasted because those speakers where probably not designed for combined active subwoofer use.
 

Tom C

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I heard Muons at the HiFi News audio show in Windsor about five years ago. They played loud and clean, to be sure, but I didn’t find the sound quality of my LS50’s to be less enjoyable. The Muons were set up in a very large room, and they filled the space nicely, but the sound was just louder, not so much better quality.
Now, Blades aren’t Muons, and LS50’s aren’t Blades or Muons. I’m encouraged to hear that those who pay such high prices for speakers actually get something for their money. But as these things are an individual’s choice, I think doing 7.1 or 5.2.4 in LS50 makes much more sense, cost wise. A person’s got to have some self control.
 

Tom C

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I like fries with mayo, rib eye steaks, and subs crossed at 125Hz.
 

Tom Schneider

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I have KEF LS50 Metas with a KEF KC62 sub that is crossed over in LFE mode at 90Hz. This combo seems to work well in my room and takes the low frequency struggle of the LS50s out of the equation in my room. I'm currently working on room correction now which will trigger some speaker and sub movement but at this point I have not yet looked into any EQ solution.
 

ROOSKIE

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How many good speakers don't go <80Hz? I usually cross over a active sub @~80Hz and avoid all that fatty booming sounding bass when the speakers are merged with the subs @ too high a freq.
I have yet to find a 5/5.25 driver based 2 way that does 80hrz well. Most 6.5" can barely do so at SPL in a medium large or bigger room.

There is no reason for boomy bass no matter what frequency you use. I do not have boomy bass in any of my testing situations which range from mains crossed @50 to mains crossed over 150.(making the mains essentially towers or 3 ways with separate woofers) I do use PEQ but even without it I could get great sound with effort, much better than mains alone.
 

muad

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True, a pair of Metas plus 12" subs crossed over at 150hz with a L-R filter, with the subs place around 2 ft away from the mains (1/4 wavelength), and using Dirac Live to tame what can be tamed won't be as good as a pair of Blade Metas (especially at higher volumes, but who listens at 90db+ consistently)? But for most people they will be one of the very best systems they could have--especially in a smaller listening space.

And of course without external subs, the Blades will also lack the capability of taming room nodes, and no one says you could not add a third stragegically placed small sub to the LS50 Meta + subs to tame a room node or two if that proves to be a major problem.

Ultimately, the biggest issue with the Meta set up is it might on occasion seem slightly strained (distorted) and less effortless than the Blades, particularly in the midbass/lower midrange during peaks (90+ db). Undoubtedly means they won't sound as big as the Blades, but what does?

Considering a LS 50 Meta + subs +Dirac can be obtained for between $4-5k, maybe less, that seems like a shockingly small performance compromise to me.
Assuming no crossover to a sub, a single LS50M gets 1.5mm xmax playing 96db at 150hz. (Calculated as a 4.5in driver). I'm surprised there would be distortion at 90db in the midbass.
 
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