• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

KEF R Series with MAT white paper

HarmonicTHD

Major Contributor
Joined
Mar 18, 2022
Messages
3,326
Likes
4,835
Hi David. It was under the impression that the optimal size of a speaker would not only depend on the listening distance but also on the room size.
I have been on the lookout for upgrading my old KEF R3 in a 2.1 setup to a new 5.1 KEF R surround setup, where I will be using the R3 as surround speakers. The room is big, 6 x 8 x 2.7 meters, and openly connected to areas with about the same volume jointly. However, as I sit around 2.6 meters away from the speakers, I am in doubt if I should go for the R7 or R11 to go with the R6. Ideally, I would not like to compromise on the stereo image, but at the same time, I also want the speakers to sound full and project a big wall of sound. On the other hand, I would rarely go past 80 db in average listening level. Would I be shooting myself in the foot by going for the R11 as I sit less than 3 meters away?
No the R11 will be fine at 3m. (I heard the Reference 5 at about that distance and it was fine).

But either way, get at least two subs for that room size of yours, because you will need it to „pressurize“ it and secondly to even out the inevitable room modes. And remember according to the Harman preference studies, that bass makes up ca 30% of the overall preference. (So if you want it to sound full, what ever that means exactly, don’t skimp on bass).
 
  • Like
Reactions: exm

tmj

New Member
Joined
May 7, 2023
Messages
4
Likes
2
No the R11 will be fine at 3m. (I heard the Reference 5 at about that distance and it was fine).

But either way, get at least two subs for that room size of yours, because you will need it to „pressurize“ it and secondly to even out the inevitable room modes. And remember according to the Harman preference studies, that bass makes up ca 30% of the overall preference. (So if you want it to sound full, what ever that means exactly, don’t skimp on bass).
My listening distance is less than three meters, as David suggested as the minimum listening distance for the R11. Regarding subwoofers, I am not looking for earth-shattering bass and I have found a lucky spot for the single subwoofer that provides a nice even response at the MLP. However, I have thought about adding a second sub in the future. Regarding the fullness, I can tell you that my previous speakers, B&W CM8 S2, provided a bigger soundstage with more weight and depth to its sound when compared to the KEF R3, despite the latter sounding much less colored and much more detailed. I hypothesize the lack of "fullness", as I called it, is mainly due to the volume of the room.
 

exm

Active Member
Joined
Sep 21, 2021
Messages
266
Likes
225
My Reference 5 are about 4M away from my listening position and it’s no problem. The R11s are great speakers; I would go for it.
 

marc111

New Member
Joined
May 13, 2023
Messages
3
Likes
0
David and others,

I'm very interested in the R11 Meta. It appears to have some great qualities. But I have a question about the low end extension. It has 4 6.5 inch woofers and a fairly large cabinet. But the 3db point is 48hz, which seems high. Compare to ML XTF 100 - 3 6.5 woofers with a 3db low of 31 hz. Is this a design choice? Thanks.
 

HarmonicTHD

Major Contributor
Joined
Mar 18, 2022
Messages
3,326
Likes
4,835
David and others,

I'm very interested in the R11 Meta. It appears to have some great qualities. But I have a question about the low end extension. It has 4 6.5 inch woofers and a fairly large cabinet. But the 3db point is 48hz, which seems high. Compare to ML XTF 100 - 3 6.5 woofers with a 3db low of 31 hz. Is this a design choice? Thanks.
Were both measured equally? Can you give the source if the second speaker‘s data?
 

fineMen

Major Contributor
Joined
Oct 31, 2021
Messages
1,504
Likes
680
David and others,

I'm very interested in the R11 Meta. It appears to have some great qualities. But I have a question about the low end extension. It has 4 6.5 inch woofers and a fairly large cabinet. But the 3db point is 48hz, which seems high. Compare to ML XTF 100 - 3 6.5 woofers with a 3db low of 31 hz. Is this a design choice? Thanks.

The -3dB point doesn't tell how the speaker will perform in a specific room. There is a general room gain, and not to forget the room resonances. The peaks are more prominent to the human ear than the associated dips. Even if in the mathematical grand total the average of bass is tilted down, the ear weighs it differently more leaning towards the tops of the peaks. I hope that makes sense to you.

I think the -10dB point is more relevant.

In my personal understanding KEF tuned the speakers to a quite shallow tilt in order to cope with room resonances. In my very large room the bass of my R3s goes down to 30Hz at or above the level of the lower mids. And if I chose a listening position close to a wall behind me, the bass is too much and needs equalization--level it down.

Anyway, to not use an equalizer for the bass range is an anachronism. To ask for perfection without doesn't make any sense. It is not achievable. Todays standards are (very) high, and every room is still different, as are the relative positions of speakers and listener(s).
 
  • Like
Reactions: pjn

muad

Senior Member
Joined
Jun 8, 2019
Messages
420
Likes
481
Looking at the R3 vs R3 meta measurements we have:

These are the KEF official measurements. The newer meta measurements are of a higher resolution, but look pretty similar in the LW. The early reflections are more different than the LW and SP . Only possible if the DI is different, which they are in these measurements.

newplot.png


Now looking at the ASR R3 vs KEF R3 meta official measurement:

The differences here track much better. The LW, ER, SP all show differences and improved linearity. The interesting thing is the DI. That to me looks within margin of error, and I would consider them identical. Makes me think you could easily make the R3 sound exactly like the R3 meta?



newplot (1).png
 

EdJ

Member
Joined
Apr 29, 2023
Messages
11
Likes
0
with the discounting of the last generation non meta I am thinking about buy r3 (non meta) or r7. I have a sub and will use room correction. Will I hear a difference in 2.1? Will the meta sound any better in a bad room? I am considering the r2 meta or r6 meta for the center, will they match. These seem to be better rated. Will the r7 sound better than the r3. This is a large 15'x32'x 10' ceilings with lots of reflections. I can place the r7 9' appart because of furniture but can move the r3s further appart. Main listening is 13' from the front wall and I want it to be good stereo from there to the back of the room, but want the center to be able to hit seats on the sides in front of the main listening area. other choice is martin logan xt f100 or b100 and c100. I figure kef will be better for ht, and the ml better for music, but it's hard to tell without them in the room.
 

stren

Active Member
Forum Donor
Joined
Jan 9, 2020
Messages
255
Likes
309
Cheaper at Kef now for R7/R11 - still though I'm torn - R7 pair at $2K or wait and pay a bit more for the blue R3M...
 

songOVERsound

Active Member
Joined
Mar 11, 2023
Messages
105
Likes
53
Usually it's 3 times the furthest driver spacing. So 2ft should be enough.
Thanks, that would be awesome. The mid-driver/tweeter is a bit low…

But is it just me, or is the current deal for them extremely good? I know very little about KEF, but do know that some mastering engineers use them.

I’m also set to get the Trinnov so I could Bi-amp them with Trinnov’s active filters which would be pretty epic. Another thing I didn’t realize about KEF is that they allow for true bi-amping
 

Beave

Major Contributor
Joined
May 10, 2020
Messages
1,393
Likes
3,015
What do you mean by KEFs "allow for true bi-amping?"
 

songOVERsound

Active Member
Joined
Mar 11, 2023
Messages
105
Likes
53
What do you mean by KEFs "allow for true bi-amping?"
Although passive filters will still be in play, when you set the posts on the back accordingly, the bass drivers are 100% isolated from the midrange/tweeter. Allowing for Trinnov to manipulate crossover slopes slightly, FIR filters, phase etc. also modifications can be done to crossover network keeping in mind specifications of drivers.

PMC is infamous for claiming speakers are bi-amped when they are instead bi-wired. I am in the camp that believes “bi-wiring” is snake oil in that running parallel conductors allows for doubling ampacity the wires can handle or lowering resistance slightly, but the same increases can be had by increasing the size of the wire and bridging the connections at the posts.
 

Beave

Major Contributor
Joined
May 10, 2020
Messages
1,393
Likes
3,015
What is it about PMC speakers that makes the bi-wirable but not bi-ampable? Something about their crossover topology?
 

songOVERsound

Active Member
Joined
Mar 11, 2023
Messages
105
Likes
53
What is it about PMC speakers that makes the bi-wirable but not bi-ampable? Something about their crossover topology?
I looked briefly but couldn’t find the exact info on it. It may have been something to do with PMC having amp packs on their speakers and claiming that they are active speakers, when really it’s just a self powered 3-way speaker that has passive crossover network. It was studio speakers back in the day.

I digress, I still think that bi-amping (vs bi-wiring) speakers is an underrated option
 

songOVERsound

Active Member
Joined
Mar 11, 2023
Messages
105
Likes
53
Usually it's 3 times the furthest driver spacing. So 2ft should be enough.
I reached out to KEF. Hopefully they get back to me. The only thing that throws me off, is Geithains listening distances. their drivers are all placed in front of each other yet the listening distances are 2 meters + for most models
 
Top Bottom