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KEF Q Meta is Coming

This man of audio advice claims things like tweeter gap damping and motor decoupling of the 10 cm uni-q's, with an example picture of a reference driver array. (from about 3:50) Would they have opened a cabinet and studied that, or where does that information comes from?
We give many reviewers, especially the ones who have the product before launch, an info sheet containing things like tech specs, new and interesting technologies, finishes and prices. As they have to make their reviews and film them before much of the information is publicly available, we need to give them the info specifically.
It's true, though. The UniQs all have a gap damper and there's motor decoupling in the small UniQ.
 
We give many reviewers, especially the ones who have the product before launch, an info sheet containing things like tech specs, new and interesting technologies, finishes and prices. As they have to make their reviews and film them before much of the information is publicly available, we need to give them the info specifically.
It's true, though. The UniQs all have a gap damper and there's motor decoupling in the small UniQ.
That's great. I'm very interested in the white paper. I allready liked KEF in the eighties, but couldn't afford my favorite ones. Then my Tannoy mercuries were stolen and the insurance money was just enough for the KEF RR 104AB that a local shop happened to have second hand. Since than I am sort of married to the brand, also because the 3 hifi stores in my town Groningen don't have KEF...
 
Same way Mesanovic does.

I see. I was confused because the concept I was discussing was not using a woofer on the baffle, but instead only using two side-firing woofers. I thought you were taking about the same setup.

It looks like Mesanovic is using a front woofer, then using the side-firing woofers for cancellation. Interesting design. I'd like to hear it some day.
 
Czech review of the KEF Q Concerto Meta with some measurements:


Attached screenshot is the frequency response on-axis (red, 0 degrees) and off-axis (black, 30 degrees).
 

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Hi Opal, Rõlnnbacke,

Don't worry, the new Q Meta doesn't sound as good as R Meta. Besides, the R Series has a more robust construction, nicer finishes and higher maximum output.
The aim with Q series is to bring the best sound to as many people as we can. Our opinion on "the best sound" is a 3-way speaker. This is why it was a priority to bring this architecture to the Q Meta.

Hi AOR, I can definitely see the distortion/SPL improvements going to a 3-way but what I've personally noticed when comparing the LS50 to the R3 being able to instantly switch back and forth is the LS50 is a more pure "point-source" and what I perceive as more natural. I get that the benefits of a 3 way may outweigh the point source presentation for most people but has anyone noticed this in listening tests? I'm curious why KEF hasn't used something similar to the 2-way driver in the LS50 crossed around 150-200Hz in a 3 way, it seems that you would have the lower distortion of the 3 ways combined with the more pure point source of the 2 ways if you did this.
 
Very curious to see the actual measurable difference between the Q150 which can be had easily for $300-349 and the new Q1 Meta which is listed as retail $599 at retailers, I have my doubts its worth the double price over what the previous gen can be had for.
 
Hi AOR, I can definitely see the distortion/SPL improvements going to a 3-way but what I've personally noticed when comparing the LS50 to the R3 being able to instantly switch back and forth is the LS50 is a more pure "point-source" and what I perceive as more natural. I get that the benefits of a 3 way may outweigh the point source presentation for most people but has anyone noticed this in listening tests? I'm curious why KEF hasn't used something similar to the 2-way driver in the LS50 crossed around 150-200Hz in a 3 way, it seems that you would have the lower distortion of the 3 ways combined with the more pure point source of the 2 ways if you did this.
Hi Aaron,

That's a good question. I don't know if I can give a short answer to that...

When coming up with a loudspeaker design, the first thing that's decided, is usually the number and type of drivers. This decision is informed from the science of electroacoustic comprise and the art of balancing those compromises. Many people (including me at one point) decide that the best loudspeaker is a full range driver in a sealed cabinet. This is maybe the "purest" loudspeaker architecture. All the sound actually comes from a single drive unit, and the binding posts are directly connected to the terminals of the driver. However, as many on here would point out, a speaker like that is not very good at many aspects of sound reproduction - Can't play loud, can't play low, can't really play high, can't deliver an even on and off-axis sound. That being said, they've always had a great following from their "point-source-like" qualities.

I believe the LS50 is so popular for similar reasons, albeit with fewer compromises. It can play lower, it has a nice tweeter for HF, and the sound is very spatially consistent. This has only been possible with around 40-45 years (at time of writing) of focussed development. As such, the drive units are very specialised, pushing the 2-way coaxial acoustic concept as far as possible. There are, of course, penalties to pay for this. One facet of the performance of the LS50 that can really benefit from having an extra drive unit is the distortion. The THD is pretty reasonable, but, the IMD suffers. This is the same for all 2-way coaxs, and aside from using a larger coax, such as an 8" or a 10", there's nothing to be done. As the little 5.25" LMF (with a hole in the middle) on the LS50 is told to reproduce bass, they can be overdriven relatively easily, especially with modern high power amplifiers. This, again, would benefit from handing over to a "real" bass driver that's much more resilient.

Once a third driver is added, the design direction opens up. The main decision at this point, IMO, is whether your midrange will use an underhung or overhung voice coil. Quite a specific thing, but here's where that choice could lead.

Overhung:
  • More excursion so can be crossed lower (More like a point source + sub)
  • Heavier coil (less efficient)
  • More motion (more IMD)
  • More motor non-linearities (due to more non-linear BL(x))
  • More expensive due to the extra copper in the coil
  • Higher power handling
  • Taller motor (physically bigger, and you have to use larger shorting rings etc.)
OR
Underhung:
  • Less excursion so must be crossed higher
  • Light coil (efficient)
  • Light surround
  • Less motion (less IMD)
  • Very linear motor (Very consistent BL(x))
  • Cheaper (all other things being equal)
  • Lower power handling
  • Smaller

So if we can use an underhung design, we will, in which case the only outstanding problems/points to consider are:
Higher crossover - solved (mostly) by designing a really good crossover using the absolute best measurements we can get our hands on.
Lower power handling - Usually not a problem on midranges in hifi, due to the pretty high crest factor. (See the LS60W Whitepaper for more details on research we've done in this area). Basically if you were pumping enough music power into a Q Concerto Meta such that the midrange burnt, you'd fry your eardrums.

Back to your original question, taking an LS50 and adding a sub, but crossing it quite high (150-200) would certainly work, and certainly improve the sound. I believe YouTuber Jay's Iyagi did just that. However, when presented with the opportunity to make a 3-way from scratch, the crossover points usually fall about an octave above that due to some of the specifics of what makes a good dedicated midrange driver.
 
It looks like Mesanovic is using a front woofer, then using the side-firing woofers for cancellation. Interesting design. I'd like to hear it some day.
The front drivers are HF and MF, down to 150 Hz. So the side woofers are for everything below 150 Hz and also cardiod cancellation from 150 Hz to 500 Hz. Works as advertised for me with eq only necessary up to about 275 Hz. From there in-room-response follows their "estimation" in my living room.
 
Hi AOR, I can definitely see the distortion/SPL improvements going to a 3-way but what I've personally noticed when comparing the LS50 to the R3 being able to instantly switch back and forth is the LS50 is a more pure "point-source" and what I perceive as more natural. I get that the benefits of a 3 way may outweigh the point source presentation for most people but has anyone noticed this in listening tests? I'm curious why KEF hasn't used something similar to the 2-way driver in the LS50 crossed around 150-200Hz in a 3 way, it seems that you would have the lower distortion of the 3 ways combined with the more pure point source of the 2 ways if you did this.
This is basically the approach of the Blade which uses the Reference/Blade Uni-Q and clusters the woofers closely around the coax driver.
 
Hi Aaron,

That's a good question. I don't know if I can give a short answer to that...

When coming up with a loudspeaker design, the first thing that's decided, is usually the number and type of drivers. This decision is informed from the science of electroacoustic comprise and the art of balancing those compromises. Many people (including me at one point) decide that the best loudspeaker is a full range driver in a sealed cabinet. This is maybe the "purest" loudspeaker architecture. All the sound actually comes from a single drive unit, and the binding posts are directly connected to the terminals of the driver. However, as many on here would point out, a speaker like that is not very good at many aspects of sound reproduction - Can't play loud, can't play low, can't really play high, can't deliver an even on and off-axis sound. That being said, they've always had a great following from their "point-source-like" qualities.

I believe the LS50 is so popular for similar reasons, albeit with fewer compromises. It can play lower, it has a nice tweeter for HF, and the sound is very spatially consistent. This has only been possible with around 40-45 years (at time of writing) of focussed development. As such, the drive units are very specialised, pushing the 2-way coaxial acoustic concept as far as possible. There are, of course, penalties to pay for this. One facet of the performance of the LS50 that can really benefit from having an extra drive unit is the distortion. The THD is pretty reasonable, but, the IMD suffers. This is the same for all 2-way coaxs, and aside from using a larger coax, such as an 8" or a 10", there's nothing to be done. As the little 5.25" LMF (with a hole in the middle) on the LS50 is told to reproduce bass, they can be overdriven relatively easily, especially with modern high power amplifiers. This, again, would benefit from handing over to a "real" bass driver that's much more resilient.

Once a third driver is added, the design direction opens up. The main decision at this point, IMO, is whether your midrange will use an underhung or overhung voice coil. Quite a specific thing, but here's where that choice could lead.

Overhung:
  • More excursion so can be crossed lower (More like a point source + sub)
  • Heavier coil (less efficient)
  • More motion (more IMD)
  • More motor non-linearities (due to more non-linear BL(x))
  • More expensive due to the extra copper in the coil
  • Higher power handling
  • Taller motor (physically bigger, and you have to use larger shorting rings etc.)
OR
Underhung:
  • Less excursion so must be crossed higher
  • Light coil (efficient)
  • Light surround
  • Less motion (less IMD)
  • Very linear motor (Very consistent BL(x))
  • Cheaper (all other things being equal)
  • Lower power handling
  • Smaller

So if we can use an underhung design, we will, in which case the only outstanding problems/points to consider are:
Higher crossover - solved (mostly) by designing a really good crossover using the absolute best measurements we can get our hands on.
Lower power handling - Usually not a problem on midranges in hifi, due to the pretty high crest factor. (See the LS60W Whitepaper for more details on research we've done in this area). Basically if you were pumping enough music power into a Q Concerto Meta such that the midrange burnt, you'd fry your eardrums.

Back to your original question, taking an LS50 and adding a sub, but crossing it quite high (150-200) would certainly work, and certainly improve the sound. I believe YouTuber Jay's Iyagi did just that. However, when presented with the opportunity to make a 3-way from scratch, the crossover points usually fall about an octave above that due to some of the specifics of what makes a good dedicated midrange driver.

Thanks for the detailed response. Just to clarify when I mentioned using an LS50 driver as a midrange I meant like in a 3 way bookshelf to maintain the point source down to 150-200Hz. When subwoofers are in the mix I usually cross my LS50 in the 90-120Hz range which also greatly reduces cone excursions.
 
Hi AOR, I can definitely see the distortion/SPL improvements going to a 3-way but what I've personally noticed when comparing the LS50 to the R3 being able to instantly switch back and forth is the LS50 is a more pure "point-source" and what I perceive as more natural. I get that the benefits of a 3 way may outweigh the point source presentation for most people but has anyone noticed this in listening tests? I'm curious why KEF hasn't used something similar to the 2-way driver in the LS50 crossed around 150-200Hz in a 3 way, it seems that you would have the lower distortion of the 3 ways combined with the more pure point source of the 2 ways if you did this.
Whilst very different in a lot of ways, this is what the Amphion One25a does.

Point source/time aligned mid and tweeter handing off to a 10” sub crossed over at 100hz.

But the bass driver is big and it’s active.
 
I auditioned Q Concerto in comparison with R3M and Q3M at a local dealer today, here are my thoughts:
1. It's not on par with R3M in pretty much every field, especially of bass extension, clarity and overall smoothness.
2. The sensitivity seems lower than R3M, same amplifier settings resulted a lower output level.
3. Concerto's tonality is brighter than R3M and Q3M, more energy in the 10k region, I think R3M and Q3M is easier on my ears and flatter.
4. Directivity is great, stereo imaging is fine.
5. Can't judge the bass due to poor room treatment and placement, but what I hear is a bit disappointing considering the woofer size.
 

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Looks like a nice set of upgrades. Like the smaller coax + 3-way direction too.
 
I auditioned Q Concerto in comparison with R3M and Q3M at a local dealer today, here are my thoughts:
1. It's not on par with R3M in pretty much every field, especially of bass extension, clarity and overall smoothness.
2. The sensitivity seems lower than R3M, same amplifier settings resulted a lower output level.
3. Concerto's tonality is brighter than R3M and Q3M, more energy in the 10k region, I think R3M and Q3M is easier on my ears and flatter.
4. Directivity is great, stereo imaging is fine.
5. Can't judge the bass due to poor room treatment and placement, but what I hear is a bit disappointing considering the woofer size.
Were you not tempted to test those Ref1M behind? :D
 
Hi Aaron,

That's a good question. I don't know if I can give a short answer to that...

When coming up with a loudspeaker design, the first thing that's decided, is usually the number and type of drivers. This decision is informed from the science of electroacoustic comprise and the art of balancing those compromises. Many people (including me at one point) decide that the best loudspeaker is a full range driver in a sealed cabinet. This is maybe the "purest" loudspeaker architecture. All the sound actually comes from a single drive unit, and the binding posts are directly connected to the terminals of the driver. However, as many on here would point out, a speaker like that is not very good at many aspects of sound reproduction - Can't play loud, can't play low, can't really play high, can't deliver an even on and off-axis sound. That being said, they've always had a great following from their "point-source-like" qualities.

I believe the LS50 is so popular for similar reasons, albeit with fewer compromises. It can play lower, it has a nice tweeter for HF, and the sound is very spatially consistent. This has only been possible with around 40-45 years (at time of writing) of focussed development. As such, the drive units are very specialised, pushing the 2-way coaxial acoustic concept as far as possible. There are, of course, penalties to pay for this. One facet of the performance of the LS50 that can really benefit from having an extra drive unit is the distortion. The THD is pretty reasonable, but, the IMD suffers. This is the same for all 2-way coaxs, and aside from using a larger coax, such as an 8" or a 10", there's nothing to be done. As the little 5.25" LMF (with a hole in the middle) on the LS50 is told to reproduce bass, they can be overdriven relatively easily, especially with modern high power amplifiers. This, again, would benefit from handing over to a "real" bass driver that's much more resilient.

Once a third driver is added, the design direction opens up. The main decision at this point, IMO, is whether your midrange will use an underhung or overhung voice coil. Quite a specific thing, but here's where that choice could lead.

Overhung:
  • More excursion so can be crossed lower (More like a point source + sub)
  • Heavier coil (less efficient)
  • More motion (more IMD)
  • More motor non-linearities (due to more non-linear BL(x))
  • More expensive due to the extra copper in the coil
  • Higher power handling
  • Taller motor (physically bigger, and you have to use larger shorting rings etc.)
OR
Underhung:
  • Less excursion so must be crossed higher
  • Light coil (efficient)
  • Light surround
  • Less motion (less IMD)
  • Very linear motor (Very consistent BL(x))
  • Cheaper (all other things being equal)
  • Lower power handling
  • Smaller

So if we can use an underhung design, we will, in which case the only outstanding problems/points to consider are:
Higher crossover - solved (mostly) by designing a really good crossover using the absolute best measurements we can get our hands on.
Lower power handling - Usually not a problem on midranges in hifi, due to the pretty high crest factor. (See the LS60W Whitepaper for more details on research we've done in this area). Basically if you were pumping enough music power into a Q Concerto Meta such that the midrange burnt, you'd fry your eardrums.

Back to your original question, taking an LS50 and adding a sub, but crossing it quite high (150-200) would certainly work, and certainly improve the sound. I believe YouTuber Jay's Iyagi did just that. However, when presented with the opportunity to make a 3-way from scratch, the crossover points usually fall about an octave above that due to some of the specifics of what makes a good dedicated midrange driver.
As someone who clearly understands the tradeoffs and is familiar in detail with the speakers. What is better in your opinion LCR Q6s or LR Concerto and Q6 centre?
 
As someone who clearly understands the tradeoffs and is familiar in detail with the speakers. What is better in your opinion LCR Q6s or LR Concerto and Q6 centre?
The Q6 and Q Concerto will have different bass. Aside from that, they are pretty similar. It's more a matter of size and placement. You can put the Q6 right up against a wall as it's sealed. The Q Concerto can't be put right against a wall due to the rear port, but the cabinet is smaller. The Q Concerto will have better bass extension, but the Q6 will have tighter bass, due to the sealed cabinet.
Neither is better than the other, both are great speakers.
The tonality of the speakers are very similar, so there's no concern there...
 
The Q Concerto will have better bass extension, but the Q6 will have tighter bass, due to the sealed cabinet.
When put up against a wall/eq-ed for compensation, could the Q6 eventhough go deeper, below the tuning frequency of the Q Concerto?
 
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