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KEF R3 Speaker Review

hardisj

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While the driver has likely changed since then, I tested the original R-series concentric back around 2014. Here's a link to the data if you're interested in seeing the raw driver performance of that driver (no enclosure, no crossovers; driver mounted on a large flat baffle).

https://www.erinsaudiocorner.com/driveunits/kef-r300-drive-unit/


I liked the driver so much that I installed it in to my car. That setup was bad-ass. :D




 
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For headphones its only ~63% that prefer the actual Harman curve, the others prefer more bass or more treble.
I think it would be interesting to do the Harman tests today with a group of "well behaved" speakers with varying degrees of neutrality and see what the verdict is. Back when most of these listening tests occurred, the non-neutral speakers had other serious flaws that couldn't be overlooked - yet all of our speaker science is based off of that.
 

Koeitje

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I think it would be interesting to do the Harman tests today with a group of "well behaved" speakers with varying degrees of neutrality and see what the verdict is. Back when most of these listening tests occurred, the non-neutral speakers had other serious flaws that couldn't be overlooked - yet all of our speaker science is based off of that.
I already stated what the results would be, the Harman curve for headphones is what a high end speaker well behaved speaker would perform like in an average room...
 
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I tried kef r7 , the bass is much more satisfying than the r3 , however it sounded more metallic (maybe due to placement tho right speaker was on a corner).
In general, the r3 felt more on the lean side so its not for everyone, but i would imagine it to sound good with proper subwoofers.
 
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Amirm seems to prefer Haman Group products. Even if the preference score is high, the pinkpanda rating may be low.

The pink panda is too subjective. Is that because you have a friend in the Haman Group?
 
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amirm

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Thread Starter #109
Amirm seems to prefer Haman Group products. Even if the preference score is high, the pinkpanda rating may be low.

The pink panda is too subjective. Is that because you have a friend in the Haman Group?
I do have friends at Harman. And my company has business relationship with them.

You can choose to go by that suspicion, or believe that my preference is outside of personal bias.
 

spacevector

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I can't. The measurement system is under the control of Klippel software and I have no way of messing with datapath. Others can easily simulate that though.
You already have all the data to apply said EQ in your hi-fi, no?

Just to clarify, I am asking you to apply the EQ as deduced from NFS data to your hi-fi and compare the EQ'd KEF against the Revel.
 
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Here's an interesting blind test that involves the R3 from a user that posts both on here and on AVS: https://www.avsforum.com/forum/89-s...rra-2ex-blind-listening-results-informal.html

The Sierra 2-EX hasn't been reviewed here yet (the original Sierra 2 has), but assuming the preference rating falls between the Sierra 2 and the R3 (which would be a fair assumption since the EX is an upgraded Sierra 2 and the R3 is the second highest rated speaker so far), it's another data point showing a lower rated speaker subjectively sounding better - this time with perhaps more validity as the test was done blind.
 
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Haint

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I think it would be interesting to do the Harman tests today with a group of "well behaved" speakers with varying degrees of neutrality and see what the verdict is. Back when most of these listening tests occurred, the non-neutral speakers had other serious flaws that couldn't be overlooked - yet all of our speaker science is based off of that.
Preference is less important than having an industry standard across both creation and consumption. Something mastered on flat pro studio monitors (which I'm assuming describes a majority of modern film, music, and game studios) is never going to sound right on some nonsense from Zu Audio. Artistic coloration and preference curves should be left to the studio engineers, not speaker manufacturers, and certainly not both.
 
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amirm

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You already have all the data to apply said EQ in your hi-fi, no?

Just to clarify, I am asking you to apply the EQ as deduced from NFS data to your hi-fi and compare the EQ'd KEF against the Revel.
I just don't have the time. Someone just got anxious that I had not tested their gear and I had to ship it back without testing. The purpose of these reviews is to post the objective data. Other side projects will have to be performed by someone else as I work through the mountain of hardware waiting to be tested.
 
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Preference is less important than having an industry standard across both creation and consumption. Something mastered on flat pro studio monitors (which I'm assuming describes a majority of modern film, music, and game studios) is never going to sound right on some nonsense from Zu Audio. Artistic coloration and preference curves should be left to the studio engineers, not speaker manufacturers, and certainly not both.
I don't disagree with you about industry standards. My crusade has always been against the validity of the preference score as a way to determine listener preference.

The speaker the R3 lost the blind test to has good spins and overall, a neutral response. If you read the details of the blind test, the differences weren't in coloration of the response, but clarity, realism, and the harshness in the R3's.
 

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Haint

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I don't disagree with you about industry standards. My crusade has always been against the validity of the preference score as a way to determine listener preference.

The speaker the R3 lost the blind test to has good spins and overall, a neutral response. If you read the details of the blind test, the differences weren't in coloration of the response, but clarity, realism, and the harshness in the R3's.
What I was saying is the goal should be something like the Genelec, with the studio engineer adding the M16's "color" to the track. Personally, I think Amirm's preference is likely because the M16's response is much closer to the majority preferred steady state room curve.
 

laurelkurt

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I just don't have the time. Someone just got anxious that I had not tested their gear and I had to ship it back without testing. The purpose of these reviews is to post the objective data. Other side projects will have to be performed by someone else as I work through the mountain of hardware waiting to be tested.
I was getting a little anxious myself, especially in light of my other half: Now aren't you going to feel stupid if you don't get them back? How do you even answer a pointed question like that? Uhh, REALLY stupid dear. =O
 
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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:



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.
Just before the new series was released I listened to a beautiful looking pair of the R-500s at a big discount (I think the front-end was all Marantz) and I came away thinking much the same: kind of dull, thin sounding, unexciting...A few months later a small shop opened up across the street selling ATC and Focal and it took only a few moments of listening to the ATCs to realize that those old-fashioned lads in Gloucestershire with their sealed cabinets and paper cones delivered a rich, full, glorious tone that was astounding when considering their modest size and number of drivers ( the 11s and the 19s)....
 

McFly

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Just before the new series was released I listened to a beautiful looking pair of the R-500s at a big discount (I think the front-end was all Marantz) and I came away thinking much the same: kind of dull, thin sounding, unexciting...A few months later a small shop opened up across the street selling ATC and Focal and it took only a few moments of listening to the ATCs to realize that those old-fashioned lads in Gloucestershire with their sealed cabinets and paper cones delivered a rich, full, glorious tone that was astounding when considering their modest size and number of drivers ( the 11s and the 19s)....
I own the both the R3s and the SCM40s. The ATCs I will own till I die.
 

spacevector

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I just don't have the time. Someone just got anxious that I had not tested their gear and I had to ship it back without testing. The purpose of these reviews is to post the objective data. Other side projects will have to be performed by someone else as I work through the mountain of hardware waiting to be tested.
OK understood.

It seemed like you made some keen observations comparing subjective evaluation to measured data in this review. The EQ'd comparison may have furthered the understanding. Actually I'm a bit surprised that you didn't attempt to 'close the loop' after making observations about treble boost in the KEF and bass boost in the Revel but I understand you are extremely time limited.

I'm sure though that plenty of speakers will come along and hopefully at a later day you will have more time to approach this in a more relaxed manner.

I really love the extremely fast pace ASR churns these reviews out: one-a-day for a one-man show is prolific. I do wish, though, that you were able to spend a bit more time with loudspeakers which may not be as cut-and-dry as electronics.

You need an assistant.
 
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