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KEF R3 Speaker Review

Descartes

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These are two different issues, Meta improved both the frequency response of the original LS50 which could be corrected to a significant part with EQ but also reduced the driver distortions something which cannot be corrected with EQ.

So the LS50 Meta sounds better then! Now if we could get the R3 Meta! Maybe at CEDIA in September
 

daftcombo

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So, do we know why our host and many others think those speakers sound boring, or does it remain a mystery?

Would it be possible to EQ it toward goodness? Or is it all a matter of narrow directivity?
 

Descartes

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So, do we know why our host and many others think those speakers sound boring, or does it remain a mystery?

Would it be possible to EQ it toward goodness? Or is it all a matter of narrow directivity?

This site has a strong bias for all things Revel! At least they measure well but the KEFs do as well.

Which is why it is critical to listen for yourself as we all have different rooms, tastes and hearing!
 

BrokenEnglishGuy

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I find this a rather interesting question for selfish reasons :p. A second-hand pair of Genelecs cost about the same as a new R3's. I don't really care too much about active vs passive. I have more than enough amps around to power the KEF's. A big advantage of the active system is the protection that comes along with it. But I rarely play up to the limit, so not that big of a deal. I also don't need GLM, since I also have some DSP's at hand and enough tools to make proper use of them. Frequency response wise after EQ there is not that much of a difference. I'd say the Genelec is a bit smoother in DI, and a bit rougher in overall response (dashed line is the Genelec) (this includes EQ). Yes, bass droops for the KEF, but EQ and a sub will help. Obviously, the KEF has better overall directivity due to the coax nature.
View attachment 128463
Distortion wise it's a bit hard to compare. The R3 distortion was measured at 105 dB, while the Genelecs were at 96 dB. At first glance, it looks like the KEF is doing worse below 200 Hz, but if you lower the 1 to 1.5% with 10 dB, you'll get to roughly 0.3 to 0.5 %, and even at 100 Hz, it would be below 1% at 96 dB. Not as good as the Genelec, but also not that bad. Above 200 Hz it's clearly superior distortion wise. I will be using a sub anyway for below 80 Hz.

Looks-wise, I quite like both. My wife likes the KEF's better though. We have the R500's now but want to go rearrange the setup. Bookshelves just fit better in the new arrangement.
The yellow line is the kef?, above 200hz is better kef?
 

voodooless

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The yellow line is the kef?, above 200hz is better kef?

The graph I posted does not show distortion. I'm was referring to the distortion ASR tests of both.

index.php

index.php
 

Descartes

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This is a review and detailed measurements of the KEF R3 stand-mount (bookshelf) speaker. It is on kind loan from a member who sent a pair to me at great cost (they come two in a box). The R3 costs US $1,999 for a pair.

The R3 is an example of superb industrial design by KEF:


It oozes elegance and comes in a number of colors to please anyone. It is also highly differentiated by its coaxial design and gorgeous woofer.

The back side looks plain but you are not going to be looking at that:


The sharp corners make for a nice design but likely not good for diffraction effects (little speakers playing on their own at ever corner).

We have the same knobs that allow the woofer to be separated from the rest to bi-wire/bi-amp the speaker. I only tested the R3 as one unit.

Measurements that you are about to see were performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.

All measurements are reference to tweeter axis with the grill removed. Frequency resolution is 0.7 Hz (yes, less than 1 Hz) and plots are at 20 points/octave. Spatial 3-D resolution is 1 degree.

Over 800 points around the speaker were measured (from 20 to 20 kHz) which resulted in well under 1% error in identification of the sound field to almost 20 kHz where error increased a bit (likely not visible on graphs).

Spinorama Audio Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker can be used. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:

View attachment 53997

They eye averages this out to pretty flat on-axis response. While not high in amplitude, there is a broad increase in level between 3 and 10 kHz. This will hit a lot more musical notes so it may make the speaker a bit bright relative to a speaker that has some choppiness but narrow peaks.

Sensitivity is on the money with respect to company spec if you look at mid frequencies. Deep bass though is lower at around 80 dB so amplification requirements will be significant.

We can use statistical model of listening spaces to determine, using 3-D measurements we have around the speaker, what you will hear in a real room (above is anechoic or "free field" data). That gives us this likely response:

View attachment 53998

Due to well behaved off-axis response, the curve more or less shows what the on-axis did which is good. The sloping down is expected and required. Because of good "directivity" (off-axis versus on-axis), EQ should be effective and a touch of that may improve subjective performance in upper range. Otherwise the slight suck-out in 1000 to 2000 may be too audible in how it will send that range into the background a bit.

Impedance dips to 3 ohms which is quite low, emphasizing the point I made earlier about needing a good amplifier to drive these speakers:

View attachment 53999

40 Hz happens to be highest peak in the spectrum of a set of files in my music library so having the lowest impedance there is unfortunately. Another dip exists at 150 Hz.

The distortion graphs is still work in progress as I continue to fight the Klippel software to generate proper SPL measures. It seems that in this graph, despite what I reported earlier, SPLs are not trustworthy. The ratios are. So let's look at that while giving the speaker 10 volts to push it more than 2.83 volts that I use for spinorama:

View attachment 54001

As noted, this measurement takes out the room using clever filtering in Klippel software (uses the free-field response to compensate). This results in much smoother low frequencies with no need to use gating, and response down to 20 Hz. I truncated at 50 Hz however as allowing it to go below that, shoots the distortion to nearly 100% as the speaker is incapable of producing usable output that low. An effect that I could hear in the sweeps.

There is no sudden peaks or other anomalies that stand out. Very low frequency dominates (as does with all speakers tested) which due to our high threshold of hearing and masking, likely is not very audible.

I let you all study the waterfall and see if you can correlated the little wiggles in the spinorama with the graph here:

View attachment 54002

And here is our directivity shots:

View attachment 54003

We see that 0 degree doesn't land at the center of the the driver indicating that the acoustic axis is a bit lower. Or I did not quite center the mic on the tweeter (a very delicate job given the lack of protection on the driver). I went through the painful process of compensating for this (trial and error with every cycle taking 15 minutes) but it made no difference at all in the spinorama results. Not sure if this is right or wrong. Will have to ponder more on the data and/or ask Klippel.

Here is the vertical slice:



View attachment 54004

It is as pretty as single coaxial drivers due to woofer handling lower bass now.

Speaker Listening Tests
I setup the KEF R3 in the same far-field setting I have used for my other high-fi speakers in my main system. It is stand mounted with tweeter roughly at ear level with me sitting some 12 feet away. The speaker was driven by a 1,000 watt monoblock amplifier (into 4 ohm) so power availability not an issue. Fancy audiophile cable was used so no worries there.

First the good news: the type of buzzing distortion I thought I heard with KEF Q100 was not there. It was replaced by very clear response together with strong deep bass when required. Power handling was now excellent as I could turn up the speaker as much as I needed and despite only one speaker playing. The sound was clean.

Alas, once again subjective feeling was low. My standard routine is to cycle through my reference clips that I have selected during all my normal listening to sound superb on my Revel Salon 2 Speakers. Sadly hardly any of them sounded all that good here. Yes, the highs were there. The lows at times were there. But overall experience was unexciting and unengaging for lack of a better word.

To make sure my mind has not gone crazy, I replaced the R3 with Revel M16 which I recently reviewed. Wow, all that gorgeous came right back! There are two things I clearly detect:

1. Warm, fantastic mid to upper bass. I can't emphasize enough how much difference this makes and how it impacts my subjective reviews.
2. There is a "loosness" to notes that is hard to describe but notes are separated and delightfully clean and pleasant. I get this same sense when I EQ a speaker for a room.

Discussion and Conclusions
The objective measurements will nail the Olive score no doubt. And they present for the third time a conflict with my subjective listening impressions. Of course my subjective evaluation is much less reliable. I like us to allow some allowance for them to sink in though. Olive's latest tests shows people like to hear more bass than originally though. So could this be behind my preference for speakers like Revel M16? Here is its predicted-in room response:

index.php


I am really starting to think the 100 to 200 Hz region plays a much stronger role than we think in subjective sound a speaker produces. The other factor is not letting the higher frequencies dominate the mid-range. As I noted in the review, broad deviations in the measurements, despite their low level, may have a much larger subjective difference.

At some point we will have to reconcile these differences, either setting me straight on my subjective evaluations being wrong, or us not knowing all that Harman knows about good speaker sound. Let's remember that they won't release a new speaker unless it passes double blind listening tests against its competitor. No other score allows them to skip this test. Components are tweaked until they achieve this. So one wonders if this is not released to public.

For now, objective measurements are superb enough to give a thumbs up to KEF R3 and hence the choice of panther.

Personal note:
This pair of speaker cost US $211 to ship to me with insurance. This presented huge hardship for the owner to fund but he was adamant in doing his bit to help with our research into speaker technology. I will be paying for shipping back but like to also help him what he has paid to get them to me. If you like to support him the same way, and there is no pressure, just start a conversation with me and I will collect the funds to give him.

Did you compare your review with Erin?
 

Ata

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Kachda

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I think this needs to be reflected via a quick edit of the original post. One should not need to read every single post in this 55 page thread to find out that there is nothing wrong with the subjective listening to R3 other than a pesky room mode...
I think this has been requested by others as well but so far the KEF R3 still contains the initial impressions without correction for room modes. @amirm any chance of updating the impressions on the main page so that new users reading the review get the complete picture ?
 

eyes-on-you

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I don't think anyone has claimed this (in the last comments).
It was said that "Some mention that they are not very subtle, and a bit harsh...". I then went into this, using the measurements as a basis.



Interpretation of measurements is anything but "sound-la-la-land", because this is exactly what measurements are made for. The interpretation I made is actually quite obvious if you look at the in-room responses of the R3 shown by @napilopez in post#866. There is in the mentioned range around 2-3kHz the in-room response a bit too prominent.
Must everyone see it that way? No, but my argumentation is based on measurements from different sources.

View attachment 84447

It is very similar to the R7 measurement in the Pursuit Perfect system review.

I don't rely on objective reviews, but the source:
https://www.pursuitperfectsystem.com/kef-r7-hifi-speakers-review/

1622131915536.png
 

eyes-on-you

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A few keen eyes noticed I was testing the Kef R3 and caught my measurements, too, showed a dip ~1kHz. This matches everyone's response except Amir's. A couple PMs from two different people noting the shadow flare was sticking out a bit in my photos. Now, since I wasn't going "full bore" in to the Kef measurement just yet I hadn't paid attention to it. I received a pair. I knew I had already pushed one of the speaker's shadow flare in. But I hadn't checked the one on the stand yet because... well, I hadn't gotten there yet. I went to the garage to check and sure enough, the flare was sitting out about 1-2mm. Upon some investigation this is what I found:

View attachment 112562
Read the legend.

Bottom line is:
If the shadow flare isn't pushed all the way in there is a dip. One would think that flush would be the way to go. But nope. And when you look more closely it makes sense why. The shadow flare all the way in (leaving a small lip between the baffle and the mounting hole) makes the flare flush with the surround edge. Any position out from that - like flush with the baffle - leaves a small gap and causes the response to dip ~1kHz. The further out the shadow flare, the more drastic the dip. You want the shadow flare to meet the drive unit; not the baffle (well, both would be ideal but in a case of either/or, this is the route you go). And the data backs this up.


I hope this helps answer some of the questions asked here.

Hi Erin,

I can not understand clearly.

Which position corresponds to the speakar baffle and which position corresponds to the drive unit?

Can you show it with a picture?

I'm really trying hard to push it, it doesn't go any further. however, it still does not seem to cover the baffle completely.
 

tecnogadget

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It is very similar to the R7 measurement in the Pursuit Perfect system review.

I don't rely on objective reviews, but the source:
https://www.pursuitperfectsystem.com/kef-r7-hifi-speakers-review/

View attachment 132257

I am the one who uploaded the measurement referred to by member ctrl. I want to point out again that it should be taken with a grain of salt as it was done a long time ago, and the purpose was to show that the performance was very good despite being an extremely bad setup (bad positioning of speakers, only 50cm apart, inside the shelf of a large piece of furniture, in a very irregular room). I should find the time to update the data with my current setup correctly installed.

Yes, indeed the R7 measurement is very similar and I would not expect anything else above 800Hz/1kHz. What surprises me is that they are very similar below 100Hz, but that is just a coincidence of the acoustic situation of both measurements, how close both speakers were to the boundaries, and how the same room modes were excited... Anyway, I would trust the accuracy of the results of a measurement made with REW more than with Dirac.

Hi Erin,

I can not understand clearly.

Which position corresponds to the speakar baffle and which position corresponds to the drive unit?

Can you show it with a picture?

I'm really trying hard to push it, it doesn't go any further. however, it still does not seem to cover the baffle completely.

In this regard, the speaker cabinet has two circular routed recesses where the transducers (Uni-Q and Bass Driver) are located. In turn, these holes have 2 different depths. A main recess that allows the transducers to be assembled by screws to the cabinet. And then a through hole, where the rest of the transducer structure is housed inside the cabinet.

Erin's recommendation to push the Shadow Flare IN varies from unit to unit. And we're talking as little as a few millimeters, even 0.5mm. You simply have to gently push the Shadow Flare IN until it butts up against the limit of the first recess of the cabinet hole.
If you notice that it can no longer fit-in, this means that your Shadow Flare was already correctly installed, or that you have already reached the stop, therefore the job is finished, there is nothing more to do.

In case the positioning issue is still not clear. The Uni-Q (midrange and tweeter unit) coaxial concentric transducer has around the metal cone, in its outer circumference, a black plastic suspension. So you have to make sure that the inner diameter of the Shadow Flare (the ring outside the Uni-Q driver) is flush with the plastic suspension of the Uni-Q, so that the transition between the two is as seamless as possible.

I have taken the liberty of stealing the images from McFly member for visual understanding:


Sin título-1.jpg


However, IMHO for practical purposes this is just getting intro ultra picky territory. It takes good ear training, and well-internalized causality between measurements and what you hear, experience with tonal balance, house curves, etc...to perceive the difference. It depends on the degree of demand and definition of perfection of each person.
 

TLEDDY

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[
Here are the predicted in room responses of both, although at the (too) high listening distance of 12 feet for such speakers the sound power part should dominate even more, I matched them level wise at the ground tones region 200-500 Hz:

View attachment 54032

We see 2 main differences, one is the bass boost of the M16 which is often used for small speakers to compensate their early bass drop and make them sound also "larger" then they are and possibly also done for the US market where rooms are usually bigger and often have not solid walls like in Europe were the R3 was voiced. The other is the mid region were a higher level of the Revel makes something sound more "lively".

A thought: Use EQ on the R3 to match the FR (as close as possible) to a subjectively evaluated speaker that is “preferefed”. Then make the comparison.

If this has been performed already, please give me the reference. Thanks!

QUESTION ANSWERED

Beauty of Roon is that its filters can be switched on and off in a second. Boy, was that a miracle fix! Gorgeous detail was there with almost no loss in total bass energy. Indeed bass was now tighter. The "magic" that I heard in the Revel M16 was now imparted into KEF R3.
 
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eyes-on-you

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I am the one who uploaded the measurement referred to by member ctrl. I want to point out again that it should be taken with a grain of salt as it was done a long time ago, and the purpose was to show that the performance was very good despite being an extremely bad setup (bad positioning of speakers, only 50cm apart, inside the shelf of a large piece of furniture, in a very irregular room). I should find the time to update the data with my current setup correctly installed.

Yes, indeed the R7 measurement is very similar and I would not expect anything else above 800Hz/1kHz. What surprises me is that they are very similar below 100Hz, but that is just a coincidence of the acoustic situation of both measurements, how close both speakers were to the boundaries, and how the same room modes were excited... Anyway, I would trust the accuracy of the results of a measurement made with REW more than with Dirac.



In this regard, the speaker cabinet has two circular routed recesses where the transducers (Uni-Q and Bass Driver) are located. In turn, these holes have 2 different depths. A main recess that allows the transducers to be assembled by screws to the cabinet. And then a through hole, where the rest of the transducer structure is housed inside the cabinet.

Erin's recommendation to push the Shadow Flare IN varies from unit to unit. And we're talking as little as a few millimeters, even 0.5mm. You simply have to gently push the Shadow Flare IN until it butts up against the limit of the first recess of the cabinet hole.
If you notice that it can no longer fit-in, this means that your Shadow Flare was already correctly installed, or that you have already reached the stop, therefore the job is finished, there is nothing more to do.

In case the positioning issue is still not clear. The Uni-Q (midrange and tweeter unit) coaxial concentric transducer has around the metal cone, in its outer circumference, a black plastic suspension. So you have to make sure that the inner diameter of the Shadow Flare (the ring outside the Uni-Q driver) is flush with the plastic suspension of the Uni-Q, so that the transition between the two is as seamless as possible.

I have taken the liberty of stealing the images from McFly member for visual understanding:


View attachment 132378

However, IMHO for practical purposes this is just getting intro ultra picky territory. It takes good ear training, and well-internalized causality between measurements and what you hear, experience with tonal balance, house curves, etc...to perceive the difference. It depends on the degree of demand and definition of perfection of each person.

Thank you for your long explanations.

I read it from beginning to end and now I can fully understand it.

very successful!
 

phoenixdogfan

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This site has a strong bias for all things Revel! At least they measure well but the KEFs do as well.

Which is why it is critical to listen for yourself as we all have different rooms, tastes and hearing!
Everyone has their preferences, and it's unavoidable it will creep into the subjective part of the review, and I think ASR has been very upfront about them, and truthful with the objective measurements. And if Amir can be said to have a bias bias at least it runs toward something most people consider one the of the very best speaker lines out there. It's not like he has Zu Dirty Weekends as his reference. :p
 

Toni71

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I have bought a pair of R3 to complement my two Arendal subs. I've read about EQ the speakers and want to try this.
Can someone, please advice me some EQ settings in my Denon amp?

I have the next options:

63 Hz / 125 Hz / 250 Hz / 500 Hz / 1 kHz / 2 kHz / 4 kHz / 8 kHz / 16 kHz

Which should I up or down, and how much?

Thank you for the time.
 
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flipflop

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I have bought a pair of R3 to complement my two Arendal subs. I've read about EQ the speakers and want to try this.
Can someone, please advice me some EQ settings in my Denon amp?

I have the next options:

63 Hz / 125 Hz / 250 Hz / 500 Hz / 1 kHz / 2 kHz / 4 kHz / 8 kHz / 16 kHz

Which should I up or down, and how much?

Thank you for the time.
Ideally, you should use a software based parametric equalizer. That said, I'll recommend that you set both 4 kHz and 8 kHz to -2 dB.
 

Toni71

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Thank you. I am going to try the settings. I've read about a EQ correction between 2 and 3 khz for the R3 and for the r7 also something (have to read back, excuse me if I am wrong, I am a complete novice in this).
A friend has the R7 and ask me now, what he has to adjust in the EQ settings?

I listen music with a Denon X3700H with Heos. What do i need to buy to control the R3 to his best? Minidsp? A poweramp, good to 2ohm?
As said earlier, I work with two subs. Or just leave it with XT32 on, and be done with it?

Any help is much appreciated. Kind regards, Toni
 
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flipflop

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I've read about a EQ correction between 2 and 3 khz for the R3 and for the r7 also something (have to read back, excuse me if I am wrong, I am a complete novice in this).
R3 has an upward shelving treble in the PIR that starts at 2-3 kHz. It can be countered with a -2 dB high shelf filter @ 2.5 kHz. The settings I recommended in my first post serve the same purpose.
A friend has the R7 and ask me now, what he has to adjust in the EQ settings?
R7 has a bit of a dip from 2 to 3 kHz. The measurements I have access to aren't high quality enough for me to be comfortable making any EQ recommendations. Your friend should instead perform in-room measurements and EQ the bass range if he hasn't already.
I listen music with a Denon X3700H with Heos. What do i need to buy to control the R3 to his best? Minidsp? A poweramp, good to 2ohm?
As said earlier, I work with two subs. Or just leave it with XT32 on, and be done with it?
Like everyone else, you need to measure the room with a calibrated measurement microphone (e.g. MiniDSP UMIK-1), and correct the room modes with EQ.
 

TLEDDY

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Amirim quandry solved with EQ:

Beauty of Roon is that its filters can be switched on and off in a second. Boy, was that a miracle fix! Gorgeous detail was there with almost no loss in total bass energy. Indeed bass was now tighter. The "magic" that I heard in the Revel M16 was now imparted into KEF R3.
 
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