KEF Reference and Blade Meta announced, but where is the R Meta?????

[bo_knows]

Enough said...

 

[jackocleebrown]

Hi Killdozzer, really sorry about the very slow reply.

When you say: "AB amps struggle to deliver power into inductive and capacitive loads and typically the most difficult frequencies are either side of the impedance dip where the magnitude is still fairly low and the phase angle deviates from zero. Such impedances make the amplifier output stage work much harder and can cause protection systems in the amp to trigger." do you, by any chance, have easily accessible numbers on how big would be this increase in power consumption for the most difficult frequencies?

Yes, you can figure this out from EPDR. Power is inversely proportional to resistance so if you see the EPDR dropping down to 2 Ohms then the amp is going to need twice the power as the same signal level into 4 Ohms. It's very common to see EPDR dropping down to less than 2Ohms. Erin measures EPDR for most loudspeakers he reviews so you can take a quick look at a few to get an idea. Note that the extra power isn't being delivered to the speaker, it's being lost in the amp output stage. Nevertheless, it still has to be supplied by the PSU and handled by the output devices so generally an amp with a higher power rating can handle this better.

Is there any real-world use of all that excess power or do we really have 40% of our power amps just idling by?

Most of the time this excess power is doing nothing. But if you want to play near the max output of your speakers, without the amp needing to current limit, then this 40% is needed to handle these moments of extremely high dissipation in the amp output stage.

 

[Simply Stereo]

No one is wrong.

100%!!

Always remember, at one point in time, a handful of designers thought the Pontiac Aztek was a good idea.

 

[Kal Rubinson]

100%!!

Always remember, at one point in time, a handful of designers thought the Pontiac Aztek was a good idea.

I think it was a good idea. The translation into a real product was a disaster.

 

[jonfitch]

Terry from the "Pursuit Perfect System" just released this youtube video with Dr. Jack Oclee-Brown's presentation on the new KEF Blade and Reference technical changes.

Enjoy.

Kind of interesting the new trim rings around the woofer are a bit reflective, but not the shadow flare around the coaxial driver. This was the opposite with the original Reference, the waveguide ring around the coaxial was shiny but the trim ring around the woofer was dull and didn't reflect light. Since the floorstanders obviously have a lot of woofers but only 1 coaxial driver, this makes the overall frontal reflectivity a bit higher on the Metas.

 

[killdozzer]

Hi Killdozzer, really sorry about the very slow reply.


Yes, you can figure this out from EPDR. Power is inversely proportional to resistance so if you see the EPDR dropping down to 2 Ohms then the amp is going to need twice the power as the same signal level into 4 Ohms. It's very common to see EPDR dropping down to less than 2Ohms. Erin measures EPDR for most loudspeakers he reviews so you can take a quick look at a few to get an idea. Note that the extra power isn't being delivered to the speaker, it's being lost in the amp output stage. Nevertheless, it still has to be supplied by the PSU and handled by the output devices so generally an amp with a higher power rating can handle this better.


Most of the time this excess power is doing nothing. But if you want to play near the max output of your speakers, without the amp needing to current limit, then this 40% is needed to handle these moments of extremely high dissipation in the amp output stage.

Don't worry about the slow reply and once again, thank you very much for your time. It was really interesting to read your posts.

 

[Vacceo]

Hi YSC,

Thanks for your comments. One of the thing that we notice is how many of our loudspeakers are being used 20+ or 30+ years after they were produced. This is very satisfying for us to see, especially from an environmental perspective. I'm sure the non-meta Reference and Blade speakers out there will be being used for many many years to come.

Hello Doctor Oclee-Brown:

If memory serves me well, you have been working for KEF since 2004, so that means perhaps you were part of the development team that designed the IQ series since they are from around 2007. If some of your work is in them, I´d love to send you a huge thank you! (which can be extended to the people around there that also worked on them).

My set of 1,3,7,6c and 8ds have been playing sound from cd´s, lp´s, games and films since then, pretty much every day, without a single issue and to great delight.

 

[BossBunos]

Not everyone is that lucky to come across such an offer. OG Blade 1s for 12k? I would buy that even if I had the Blade 1 Meta.

Here they sell new original blades 1 and 2 for 14k euro a pair. Been to the store once when they had the kanta2 for 4k a pair (was in blue though).

 

[killdozzer]

I hope I'll live to see active Reference. I bet that would be a speaker of the year!

 

[Arnas]

I enjoy the LS50 meta but these are definitely not my cup of tea in the esthetic department! So boring looks! They should hire Sonus Faber designers an put their engineering in it!

Its you. I like Kef design or focal sopra design. Simple yet elegant.

 

[killdozzer]

I enjoy the LS50 meta but these are definitely not my cup of tea in the esthetic department! So boring looks! They should hire Sonus Faber designers an put their engineering in it!

It wouldn't be the easiest task since the design is very functional with these. The tangerine wave-guide you shouldn't touch if only for colour. The mid/woofer has those reinforcements which are also needed. The concave baffle is also calculated, it should act as if there's no baffle. Lastly, the shape of the port shouldn't be touched.

You're left with colour, material, choice of binding posts... Not that much.

But, I think the problem is people got used to it since 2012. When they first hit the market there was nothing quite like it.

 

[envydd]

Folks, I auditioned the reference 3 meta at a local dealer today along with the blades (non meta). They were matched with Parasound. The reference 3 meta was very smooth and neutral at about 75dB SPL at about 3m. The blades were wow .... 3D, the speakers vanished At high volumes the difference was more clear. At low volumes they were close.

However they were not an order of magnitude better than the R3 and the LS50M, especially considering their price points. Thank you, KEF.

 

[killdozzer]

Folks, I auditioned the reference 3 meta at a local dealer today along with the blades (non meta). They were matched with Parasound. The reference 3 meta was very smooth and neutral at about 75dB SPL at about 3m. The blades were wow .... 3D, the speakers vanished At high volumes the difference was more clear. At low volumes they were close.

However they were not an order of magnitude better than the R3 and the LS50M, especially considering their price points. Thank you, KEF.

I envy the chance you have.

I would also keep an open mind to the chance that Reference is much more than maybe this experience proved to you. It is a 4 driver / 3 way speaker that stretches to +/-3dB 43Hz and in-room to 28Hz -6dB. This probably renders a sub unnecessary to a significant portion of users (depending). And not needing a sub could be precisely this magnitude of a difference. Another thing, the magnitude, to use your word just for the sake of a conversation, could be undetectable in a small room. It doesn't have to be a magnitude better sound, which is not easy to achieve anyway, it can only be a matter of playing as good but in a bigger space. That should also be considered as a respect worthy magnitude. Saying; what LS50Meta can do in a small room, Reference 3 can do in a large. That's a nice magnitude.

 

[hardisj]

Reference 1 Meta. I like them.

 

[bo_knows]

I envy the chance you have.

I would also keep an open mind to the chance that Reference is much more than maybe this experience proved to you. It is a 4 driver / 3 way speaker that stretches to +/-3dB 43Hz and in-room to 28Hz -6dB. This probably renders a sub unnecessary to a significant portion of users (depending). And not needing a sub could be precisely this magnitude of a difference. Another thing, the magnitude, to use your word just for the sake of a conversation, could be undetectable in a small room. It doesn't have to be a magnitude better sound, which is not easy to achieve anyway, it can only be a matter of playing as good but in a bigger space. That should also be considered as a respect worthy magnitude. Saying; what LS50Meta can do in a small room, Reference 3 can do in a large. That's a nice magnitude.

Hello killdozer,

For whatever is worth, in my small but well-treated room, KEF ref 3 goes down to 28Hz flat (long tube on top, short on the bottom, and speakers 3 feet in the room from the front wall).
Currently, I don't use the sub (KEF KF92) when listening to the music, and no eq (Denon pure direct mode). For most music types (jazz, classical, and rock), I don't feel like I need a subwoofer. The cool thing about the Denon receiver is that you can switch almost immediately between speakers and subwoofer to hear the difference in the room when playing for example 60Hz tone. This combined with measurements will tell you how well the bass response is. To be honest, the sounds is so good that I'm too lazy to mess around with the Audyssey app to integrate them perfectly with the sub (the little of my free time I got, I rather spend listening to the music ). Most of my focus went to the room treatments. Attached few REW measurements to show the bass response with no eq in pure direct mode.

 

[HarmonicTHD]

Hello killdozer,

For whatever is worth, in my small but well-treated room, KEF ref 3 goes down to 28Hz flat (long tube on top, short on the bottom, and speakers 3 feet in the room from the front wall).
Currently, I don't use the sub (KEF KF92) when listening to the music, and no eq (Denon pure direct mode). For most music types (jazz, classical, and rock), I don't feel like I need a subwoofer. The cool thing about the Denon receiver is that you can switch almost immediately between speakers and subwoofer to hear the difference in the room when playing for example 60Hz tone. This combined with measurements will tell you how well the bass response is. To be honest, the sounds is so good that I'm too lazy to mess around with the Audyssey app to integrate them perfectly with the sub (the little of my free time I got, I rather spend listening to the music ). Most of my focus went to the room treatments. Attached few REW measurements to show the bass response with no eq in pure direct mode.

View attachment 203354 View attachment 203355

Can confirm. I use my KF92 to fill in the room induced nulls which unfortunately I can’t avoid by the mains positioning. (As I also simply don’t like room treatment in my living room, which of course is a personal preference).

 

[bo_knows]

Can confirm. I use my KF92 to fill in the room induced nulls which unfortunately I can’t avoid by the mains positioning. (As I also simply don’t like room treatment in my living room, which of course is a personal preference).

You can see the nulls in my graph, they are unavoidable in a small room(s). It's really frustrating to deal with them with just room acoustic treatments, one can only hope for those nulls to be narrow in bandwidth.

 

[envydd]

I envy the chance you have.

I would also keep an open mind to the chance that Reference is much more than maybe this experience proved to you. It is a 4 driver / 3 way speaker that stretches to +/-3dB 43Hz and in-room to 28Hz -6dB. This probably renders a sub unnecessary to a significant portion of users (depending). And not needing a sub could be precisely this magnitude of a difference. Another thing, the magnitude, to use your word just for the sake of a conversation, could be undetectable in a small room. It doesn't have to be a magnitude better sound, which is not easy to achieve anyway, it can only be a matter of playing as good but in a bigger space. That should also be considered as a respect worthy magnitude. Saying; what LS50Meta can do in a small room, Reference 3 can do in a large. That's a nice magnitude.

There are too many variables but this was a 500sqft room with 10K USD+ power amps etc .... I guess I made the mistake of hearing the blades. Its psychoacoustics Once you hear the blades, everything is just ok ..... Maybe I did not articulate well - The Reference 3 was very smooth, mellow and had lots of bass (my R3 is no match in that respect). However there was something about the blades that was hard to explain. I closed my eyes and I was lost.

If the Ref 1 meta sounds better than my R3, I will replace my R3. They didn't have a Ref1 in stock so I will wait. Till then I know I have a slightly inferior listening experience

 

[Arnas]

There are too many variables but this was a 500sqft room with 10K USD+ power amps etc .... I guess I made the mistake of hearing the blades. Its psychoacoustics Once you hear the blades, everything is just ok ..... Maybe I did not articulate well - The Reference 3 was very smooth, mellow and had lots of bass (my R3 is no match in that respect). However there was something about the blades that was hard to explain. I closed my eyes and I was lost.

If the Ref 1 meta sounds better than my R3, I will replace my R3. They didn't have a Ref1 in stock so I will wait. Till then I know I have a slightly inferior listening experience

Waiting comparison between R3, Ref1 meta and ref3 meta .
I suppose you need big room for Ref 3 meta?...

 

[envydd]

Waiting comparison between R3, Ref1 meta and ref3 meta .
I suppose you need big room for Ref 3 meta?...

I have a R3 and I auditioned a Ref3 meta. Both in 500sqft rooms. My own room is not treated at all but we have sectionals to absorb some sound. Also both listening configs are 10ft equilateral triangle. At the store they used expensive parasound gear. At home I use minidsp and purifi. I listened to the same songs - Pink Floyd, Norah jones and some cello

Subjective: (ref 3 meta vs r3)
- R3m is slightly smoother and refined than r3
- R3m had much more bass. No sub needed for my use.
- R3m looked more stunning.
- at louder volumes R3m opened up more.

I can live with my R3 and will add a kc62. And enjoy the music at about 75db spl. Till KEF wows me with something new.

Tldr: blades blades blades. For visual and acoustic impact! Need to create some room for it to breathe.