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KEF R3 meta Measurements

exm

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Thanks for these. I'm surprised about the difference in bass. I wonder if they updated the LF driver?
 

exm

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Considering size. But not great overall. Reference have better extension so does bigger KEFs towers. R3s always required subwoofer, no change here - I think that’s his point.

I'm using R3s as side surrounds crossing them at 80Hz (I have Reference as front 3 speakers). Really wanted to get a Reference 1 as a side speaker but unfortunately they are just too big for my living area, so I'll be upgrading the R3s to the R3 Metas. To me, they sound fantastic.
 
OP
Nuyes

Nuyes

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Judging on OP's conclusions:
"Bass is weak"

The original R3 never had that issue.

Given its size, the R3 meta has an excellent bass response (FR).

However, to achieve this beautiful bandwidth, the KEF uses ports, which lose a bit of their power at high SPL.

I respect the design of KEF's engineers.

However, contrary to the impression you might get from the FR graph, this speaker is a bit weak on momentary peaks, such as movie explosions.

Again, this is an unnecessary nitpicking about a good enough loudspeaker.
:)
 

exm

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Given its size, the R3 meta has an excellent bass response (FR).

However, to achieve this beautiful bandwidth, the KEF uses ports, which lose a bit of their power at high SPL.

I respect the design of KEF's engineers.

However, contrary to the impression you might get from the FR graph, this speaker is a bit weak on momentary peaks, such as movie explosions.

Again, this is an unnecessary nitpicking about a good enough loudspeaker.
:)

Appreciate the clarification. Thanks again for your review.
 

Music1969

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Is there a normal on axis frequency response?

A sweep from 20-20k Hz ?
 
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Nuyes

Nuyes

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Is there a normal on axis frequency response?

A sweep from 20-20k Hz ?
I do not own a Klippel NFS or an anechoic chamber.

The only thing I can do is to follow Klippel's manual and do the 'Merging nearfiled/farfield' technique.
(except ground plane.)

In my studio, 5ms (200Hz) window gating for HF is the limit, so for 3-way speakers with low crossover frequencies, I often fail to get intact FR.
 

Descartes

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Hi,
I measured the KEF R3 meta loudspeakers this time.

These speakers have just been released, but I was able to get a pre-order sample (a pair) from an audiophile in Korea.

View attachment 266010










Impedance

View attachment 266011View attachment 266012








Frequency response


View attachment 266013

I measure HF responses using a 5ms window gating.
Therefore, the crossover frequency of this speaker was located lower than I could measure, so I could not use the 'Merging Nearfield + Farfield' technique.


It has a similar LF roll-off to its predecessor.





View attachment 266014

Here's a comparison of 'ported vs sealed' responses.
(This was done with nearfiled measurements, with baffle step compensation applied).





Directivity



View attachment 266015View attachment 266016View attachment 266017View attachment 266018




Wow. That's really cool.

I'm noticing a huge improvement in the 15~20k compared to before.

On the outside, it looks like the exact same product as its predecessor, but the directivity definitely seems to be a step up.

While this may not be important to all users, I can't help but admire KEF's passion and skill in achieving performance improvements despite the seemingly identical design.

(Perhaps it's a fine-tuning of the lemon squeezer on tweeter?)




Beamwidth


View attachment 266019View attachment 266020


It looks as complete as anything you'll see in this price range.
(In South Korea, it's currently available for around $1,700 to $1,800).










Polar plot



View attachment 266021View attachment 266022



This loudspeaker shows almost perfectly smooth attenuation, not only in the front, but also in the sides and back.




Total Harmonic Distortion

I am representing THD relative data as CHD.
This is the percentage of each HD component based on the average SPL from 200 Hz to 10 kHz.

View attachment 266023View attachment 266024View attachment 266025View attachment 266026


You can hear a very clean response at 85dB SPL and even at 95dB SPL.
It's flawless.




Multitone test

View attachment 266027View attachment 266028

Multitone distortion of -40 to -50 dB were measured.









I tried removing the measurement signal below 80 Hz and measuring it.
This was done to see how much the effects of MD from the woofer's high displacement motion and ports could be reduced when used with a subwoofer.



View attachment 266029










And if anyone remembers, this product also had the "shadow flare" issue that was featured in Erin's Audio Corner.
So I measured how much the MD was changed by this as well.
(The effect on FR can be seen below).

View attachment 266030







MD for each SPL.


View attachment 266031View attachment 266032



Despite the increase in output, there is very little increase in Multitone Distortion.
This is a strong defense against distortion.




Compression test

View attachment 266033


This test was performed with Multitone.
It shows a compression of only 0.5 dB even at 96 dB SPL.
Very powerful performance.






Here's a look at compression testing from the other side.

These were performed at 0.1 m and 1 m, respectively, and measured with a sine sweep.



View attachment 266034View attachment 266035


We can see that the response of the woofer increased with the increase in SPL at 45Hz.
This means that the internal air pressure along the port did not remain linear.

In other words, above a certain sound pressure, the ports in this speaker lose a little bit of their effectiveness.

(All SPL values are based on output at 1kHz @1m)






Grill test

View attachment 266036


The grille is affected by a very high Q value.







Shadow flare

View attachment 266037


I measured the impact of Shadow flare, which we introduced in EAC.
(I don't own this loudspeaker, so I wasn't able to push the part very hard).

You can see that there is a dip centered around 1 kHz.
(Pressing in the Shadow flare will correct this).




View attachment 266038





Finally, the FR deviation comparison between the two samples.

View attachment 266039





A very personal thought.

KEF's precise directional control is truly amazing.

Its predecessor was good enough, but it's even better than I expected.


If I had to pick a downside...
The bass is weak.
Also, due to the compression at high SPL, I think it would be a bit too much for me to enjoy a movie without a subwoofer.

Of course, I was just nitpicking because it was so great. :)
(I envy the owner.)
Thank you
 
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