KEF R8 Meta Dolby Atmos Speaker Review

[Deleted member 48726]

But you have no data or research to point to. So don't know what you want me to do with your comment.

It's not critique of your review, Amir. It's as professional executed as ever.

It's just that I would expect the reflected sound to take on colouration dependent of the ceiling in various degrees. And as such question the measurements to "reflect" the actual sound as these aren't intended to be listened to the normal way, on axis or somewhat off axis.

 

[dasdoing]

It's not critique of your review, Amir. It's as professional executed as ever.

It's just that I would expect the reflected sound to take on colouration dependent of the ceiling in various degrees. And as such question the measurements to "reflect" the actual sound as these aren't intended to be listened to the normal way, on axis or somewhat off axis.

I agree. How would you tweak these as a producer? personaly I would put a "ceiling" in an anechoic chamber. you can't really use a Klipple for something like that.
On the other hand, someone mentioned there is a target response from Dolby for ceiling fireing stuff? So the meassured response should be convolved with that target

 

[Deleted member 48726]

I agree. How would you tweak these as a producer? personaly I would put a "ceiling" in an anechoic chamber. you can't really use a Klipple for something like that.
On the other hand, someone mentioned there is a target response from Dolby for ceiling fireing stuff? So the meassured response should be convolved with that target

But which kind of material? -Maybe Dolby has some standard here as well. I mean, they must have defined the surface, how can they otherwise define the target frequency response for the speaker? -Or is the definition based of on-axis response?

Edit: Maybe you can tell that there is a lot I don't understand about this kind af application..

 

[juliangst]

If the speakers cannot be built into the ceiling (and they cannot), the only option is the use of ceiling-reflected Atmos-enabled speakers. This is a home and I/we will not tolerate a swarm of little boxes hanging from above. No way.

Why not on-ceiling instead of in-ceiling? I've seen a lot of people use atmos speakers like those Kefs and mount them on the ceiling aiming at the listening position. Genelecs also have ceiling mounts.

I agree that doing in-ceiling installations in not easy to do (especially when you have concrete ceilings or are renting) but mounting on ceiling speakers should be as easy as mounting on ceiling absorbers.

Most people on AV forums agree that the whole atmos ceiling reflection thing is the worst possible solution.

 

[Kal Rubinson]

Most people on AV forums agree that the whole atmos ceiling reflection thing is the worst possible solution.

Yes but, unfortunately, they are the only possible solution for some of us.

 

[juliangst]

If mounting on the ceiling isn't an option, one could also mount speakers on the top of the side wall.
I've seen some threads where people discussed this placement and prefer it over front heights.

The effectiveness of this placement of course depends on the room dimensions but if it works it should be better than upfiring speakers and it doesn't require doing anything to the ceiling.

 

[Kal Rubinson]

If mounting on the ceiling isn't an option, one could also mount speakers on the top of the side wall.

Even if they do not dangle, a scattering of little boxes in plain sight is incompatible with domestic tranquility.

 

[juliangst]

That's a fair point.
I don't have any height speakers yet either and I'm not even sure if it's really worth it for Apple Music Atmos music and Dolby Atmos upmixing in general.

 

[Billy Budapest]

View attachment 284570View attachment 284573View attachment 284574View attachment 284576

I think that the way I have the Atmos up firing speakers positioned actually minimizes the effect of sound going directly from the speakers to the listeners ears, resulting in the reflected sound predominating what is heard.

I can tell you that the setup works well. Overhead effects sound as if they are coming from a diffuse area up towards the ceiling—which most of the time is what the material calls for. I do not have rear Atmos speakers but I plan to add them with the intention of reproducing front-to-back overhead effects better.

 

[Thomas_A]

Yes but, unfortunately, they are the only possible solution for some of us.

You have to wait for the parametric array speakers...

https://opus.lib.uts.edu.au/bitstream/10453/147370/2/10.0002161.pdf

 

[pseudoid]

...the only possible solution for some of us.

...for obtaining what exactly?
I am not trying to be confrontational but when @amirm used the reference '160 degrees'; I became aghast...
A 'solution' which appears to have drawbacks and unknowns that are said to be not measurable with current practices and test apparatus.

 

[RichB]

...for obtaining what exactly?
I am not trying to be confrontational but when @amirm used the reference '160 degrees'; I became aghast...
A 'solution' which appears to have drawbacks and unknowns that are said to be not measurable with current practices and test apparatus.

Anyone with REW can wire the front channels to the up-firing speakers and show the in-room response at the listening position.

If committed to Atmos, I would mount down firing speakers or mount the Kefs on a wall.
This would not do much damage to the walls.

- Rich

 

[Kal Rubinson]

...for obtaining what exactly?

Height/ceiling/top speaker sources.

 

[dasdoing]

But which kind of material? -Maybe Dolby has some standard here as well. I mean, they must have defined the surface, how can they otherwise define the target frequency response for the speaker? -Or is the definition based of on-axis response?

Edit: Maybe you can tell that there is a lot I don't understand about this kind af application..

as others have stated, the whole concept is a little stupid.
when Bose made speakers intended to fire to walls everybody hated on them, now it's suddenly a great idea lol

 

[pseudoid]

...the whole concept is a little stupid.

"But wait!! There's more"... stupid; that is:

HTFanControl
4D Theater Wind Effect - DIY Home Theater Project
HTFanControl is an application meant to control fans in your home theater in order to create a wind effect during movies.
The program is meant to run in the background and be controlled through a web interface, typically from your smartphone.

From <https://github.com/nicko88/HTFanControl>

 

[Descartes]

This is a review and detailed measurements of the KEF R8 Meta Dolby Atmos Surround Speaker. It was kindly drop shipped to me by a member and costs US $1,600 for a pair.
View attachment 284333
The R8 meta is very compact speaker meant to be put on top of your tower surrounds (or bookshelves on stand) to fire up at the ceiling. The reflections then bounce back onto the seating locations giving a (diffused) sense of height. It eliminates the need to cut holes in the ceiling and ability to adjust their aim at will. The R8 meta is gorgeously finished and feels exceptionally solid (the "orange peel" look is reflections from my lightbox, not the speaker).

The binding posts are on the "back" side which is the taller side on the left in above picture:
View attachment 284334

There is provision for wall mounting which I assume it means surround duty with them pointing down toward listeners from side walls:
View attachment 284335

I had to do some thinking on how to measure this speaker. Clearly you don't put it on its back side in front of you and listen facing them! I realized that the aim is for you to hear its on-axis response as bounced by the ceiling and therefore, I should measure it with driver 90 degrees to microphone as I would any normal speaker. Imagine this position:
View attachment 284336

It was tricky to devise a way to securely mount it to the Klippel NFS stand but I managed to do that. Reference axis is naturally the tweeter in the center of the coaxial driver. There is a grill but as usual, I did without it.

I originally wanted to listen to them and then do the review. As you can imagine, testing an Atmos speaker is non-trivial but I have an idea on how to do it. I thought I post the measurements now since there are a few interesting things that apply to this execution and R8 Meta series in general. On the former, Dolby has strict requirement on crossover design of Dolby Atmos speakers as to reduce horizontal bleed from the speaker to the listeners. In an ideal world, all the sound would shoot up the wall and none would come from the sides.

KEF R8 Meta Dolby Atmos Surround Speaker Measurements
Again, keep in mind that on-axis frequency response means the direct sound that is going to shoot up the ceiling and reflect back to one position:
View attachment 284337

What stands out is the notch between 1 and 2 kHz (crossover frequency is 2.5 kHz). I am 99% sure this is Dolby imposed. If someone has seen the Dolby OEM requirements for the crossover, please post so we can confirm. Putting that aside, we see a lazy but wide (low Q) peaking between 5 and 10 kHz. Is that intentional tool? I don't know. The grill will attenuate that a bit. Directivity is superb (best ever seen?) so equalization should be trivial here for both factors.

I will give you the early window response even though you have to perform mental gymnastics to figure out how to map them to a speaker that is up firing at an angle:
View attachment 284338

The perfection in both horizontal and vertical axis cements in your eyes and brains when you look at beam width and directivity measurements:
View attachment 284339

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Puts a smile on my face just looking at them!

This is a sealed and super compact speaker. How will it do in distortion department? Turns out very well thank you:
View attachment 284342

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Yes, bass distortion rises at 96 dBSPL but you will be crossing these over with your sub. During the frequency sweep, even at 96 kHz, what I heard was smooth other than a tiny impairment here and there.

The meta material's job is to absorb unwanted reflections. Although it is mostly there for high frequencies, the entire response seems to be free of resonances:
View attachment 284344

Finally, here is the step response:
View attachment 284345

Conclusions
Starting with the "bones" of the speaker, there is clearly some good engineering design and magic is going on with the R8 Meta. Love to test their other speakers. For now, this up firing speaker seems to have characteristics that many other speakers would be jealous of. There are just a couple of frequency response variations that I hope we get to understand as to a) whether they are forced and b) whether the idea behind them is correct. If (b) is right, it would solve a huge problem as far as deploying these upfiring speakers instead of major hassle of sticking speaker in ceiling. More on this if I get a chance to listen to them.

For now, based on what I am seeing, I am going to highly recommend the KEF R8 Meta Dolby Atmos Surround Speakers.

------------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

Could you please provide measurements mounted on the wall facing towards the listen for ATMOS!

My ceiling is treated with acoustic panels and the sounds would no TV bounce off!

 

[Descartes]

Here is what the Dolby specified crossover looks like for the up-firing speakers:

View attachment 284424

It replicates the HRTF for making things sound as if they are coming from above you. If used for upfiring, this would need to be added with EQ (this is Audyssey MQX).

Personally, I would highly recommend that people don't do that. This is a fantastic speaker that would be easily mountable on your front and rear walls as height speakers (no goofy EQ needed, better positioning and much better sound).

So if I understand you correctly, you are saying that these speakers mounted high on the wall could be great ATMOS speakers!

 

[Descartes]

Because some are better than others and the only way to know is to measure it? We have been on a quest to find best speakers for Atmos height. This is in that series. If you don't have this application or understand it, then just move along....

Well said! Please continue the good work Amir!

 

[Descartes]

Why not on-ceiling instead of in-ceiling? I've seen a lot of people use atmos speakers like those Kefs and mount them on the ceiling aiming at the listening position. Genelecs also have ceiling mounts.

I agree that doing in-ceiling installations in not easy to do (especially when you have concrete ceilings or are renting) but mounting on ceiling speakers should be as easy as mounting on ceiling absorbers.

Most people on AV forums agree that the whole atmos ceiling reflection thing is the worst possible solution.

How would you mount them on the ceiling?

 

[pseudoid]

How would you mount them on the ceiling?

Now that you mention it, I was going to ask if a pair of these speakers would be more suitable for mounting downside-up:
Attached to the ceiling, about 2 meters apart, angled at the listener and inline with a TV screen
This configuration may allow them to be used for both DolbyAtmos + DolbyVideo.

It is troubling to think that someone would take such costly-investments and NOT pair them with other matching (and even costlier) speakers of the same manufacturer and model-line (KEF R8).

But only if you are into the Atmos-pheric living, where you have the luxury to have a separate listening room and enough patience, knowledge and expertise to know exactly when it "finally sounds just like the real dope"!

I raise the K.I.S.S. flag!