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

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I would buy a Uni-Q stuffed in Blanda bowls! A talk piece for sure.

Friend : Wtf are those???
Me : Sit down, stfu and listen.

the moment when you hit the play button, it will vibrate and bounce onto the floor and decide to go buy a KEF pre built one

 

[Crosstalk]

Thanks to your post, Ikea will be out of Blanda bowls by tomorrow night. Ikea wouldnt know what hit them.

Actually this is a good option for isolating midranges in boxes.

 

[bo_knows]

And Bushmeister with Balls of Prestige and Sphere synergy horn.

Comparison of 'Xbush Sphere synergy horn', versus 'Balls of Prestige'.

I thought I owed it to those involved in two of my larger builds to give a longer term review of these two speakers having lived with them for a few years, and over the last few weeks having done level matched, sighted and unsighted AB comparisons (which was hard work but fun!). If you are...

www.diyaudio.com

But none of those uses great coaxial as Uni-Q from LS50 Meta is, and none in cardioid configuration i mentioned with slot loaded woofer (Cabasse la Sphere perhaps). I'd really like to do it (or see someone else do it). I personally just lack a little bit of money to source a pair of LS50 Meta coax. Other stuff i can manage

Send your resume to KEF.

 

[bo_knows]

I don't as I have had both here and there is no comparison, just tap on both. Also a sphere needs ribs, the modes have just a different direction, the thin IKEA material cannot compensate the form advantage. But if you build a loudspeaker with them you can send it to me, I have at work access to professional 3-axis accelerator sensors so I could do some comparison sweeps on both LS50 and them.

Thinking "out of the box" is what matters, all the details can be worked out in time.

 

[Everett T]

Just a note, since the announcement there a more then a few Blade variations for sale on US Audio Mart...

 

[thewas]

Thinking "out of the box" is what matters, all the details can be worked out in time.

Sure, using those IKEA bowls isn't really though such, it is very popular in the DIY scene here.

 

[JRS]

Blade One Meta is truly an end game speaker. Selling my left nut for a pair, any takers?

Now who here wouldn't? Assuming of course 35K means something. Now a pair, that would be a sacrifice.

Who knows, maybe develop a taste for Italian Opera to go with the shiny new Blades.

 

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Now who here wouldn't? Assuming of course 35K means something. Now a pair, that would be a sacrifice.

Who knows, maybe develop a taste for Italian Opera to go with the shiny new Blades.

I wouldn’t, a full tower speaker means I need a bigger home, a lot bigger. So even if it’s a giveaway I will instantly put them on eBay

 

[MarkWinston]

I would happily shove the Blade One Meta into a 5 meter x 3 meter room. I would happily power them with a SMSL DA-9 even if thats all Ive got. To even own the Blade One Meta in the first place is just a dream come true.

 

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I would happily shove the Blade One Meta into a 5 meter x 3 meter room. I would happily power them with a SMSL DA-9 even if thats all Ive got. To even own the Blade One Meta in the first place is just a dream come true.

a 5x3 room is something I don't have. 5x3 Foot space is the space available for me

 

[Zvu]

I don't as I have had both here and there is no comparison, just tap on both. Also a sphere needs ribs, the modes have just a different direction, the thin IKEA material cannot compensate the form advantage. But if you build a loudspeaker with them you can send it to me, I have at work access to professional 3-axis accelerator sensors so I could do some comparison sweeps on both LS50 and them.

Ribs yes, struts no. Point of it was to leave the mid of the cabinet free for damping material for standing wave absorbtion.

Tap/knuckle test doesn't do anything usefull.

If i decide to make a pair, i'll hapilly send them to you.

 

[thewas]

I strongly doubt that just ribs will bring it on the same level and also don't agree about that the tap test doesn't give an idea about the modal spectrum and damping (see impulse hammer method), but measurements will tell in the end.

 

[MarkWinston]

a 5x3 room is something I don't have. 5x3 Foot space is the space available for me

All the same. I would shove those buggers in. Unless the speakers itself wont physically fit the room or enter the door, I would totally keep them and no other speakers for life. End game right there.

 

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All the same. I would shove those buggers in. Unless the speakers itself wont physically fit the room or enter the door, I would totally keep them and no other speakers for life. End game right there.

in my case it's absolutely like that, you can't even put them and not using them as nearfield desktop speakers, so Genelecs for the win

 

[Vineeth Kumar V]

Ya think ? Lemme continue throwing ideas.

Make circular slots on Blanda arround Uni-Q and add some felt for cardioid response in all directions. Put it on a stand made out of 25-30cm Sonotube with 8" woofer on top of it. Mount the sphere on top of it offseting it 2-3cm from woofer cone and by that you're creating a slot. Now slot loading will add few dB's and you've made acoustic filter at higher frequencies for 8" woofer and crossover will utilize fewer parts (or just go DSP active and destroy 99% of existing loudspeakers). Cross it at 200Hz with Blanded Meta Uni-Q and enjoy

Very interesting concept.
Even though not yet cardioid with a coaxial driver, all the other engineering choices look close enough in this project especially in its latest version.

FSTNT1

 

[killdozzer]

This is very interesting and thank you very much for keeping us posted. I was wondering when will Reference benefit from the research into distortion attenuating materials. This is very good news, but I also ask what advantages will be there after the Meat R series. (Although to be honest, I don't doubt KEF will have something up its sleeve. In all honesty, during a long period I've been drawn to this company, the one and only single resent I have is the 11Hz spec on their KC62, which still makes them one of the best big speaker companies out there.)

 

[KMO]

I do hope there isn't a Meat R series.

But then again, if it works? Got to go where the audio science leads, I guess.

 

[steve59]

I was being serious when I asked it the measurement experts can predict what the measured differences will sound like?

 

[jackocleebrown]

@jackocleebrown mind giving us the laydown on the new series and put some doubts to rest?

Hello @MarkWinston and @Zvu,

Thanks for the interest in the new products!

@Zvu, you have a very good knowledge of our drivers. The Concept Blade was the first time that KEF switched from plastic midrange cones to something else. We specifically wanted to achieve rigid piston operation over the entire working band of the MF driver. The solution we came up with was nodal drive + heavily ribbed LCP cage joining the voice coil to the cone. This was back in 2009! I do still really like this concept, but it is rather extreme. The benefits are that you do get a wonderfully stiff midrange with very high breakup. However, it presents some very significant challenges in the rest of the driver design. First, the mass of the cone and coil assembly is very high for a midrange driver. Which means you need a huge motor to drive it. This in turn blocks a lot of the air around the back of the cone making it very challenging for the rear acoustics. In addition, there is a significant proportion of the cone area inside the large voice coil and venting this space is tricky. The breakup of the midrange is pushed up to 9kHz, which is remarkable for a 4inch driver, but it's rather peaky. And finally, due to the large coil there's limited space for the suspension and it's difficult to achieve high excursion.

For lower cost products it was clear we couldn't use the same solution, so in around 2011 we came up with the idea of using a damped resilient link between the coil and metal cone to control the breakup. As there are no stiffening ribs or nodal drive the breakup is around 4kHz, but with careful design of the link we could damp it very effectively and end up with a very tidy response without any peaking above the passband level. The moving mass is close to a conventional driver. This was first used on Q-series, then LS50 and the original R-series. We refined the technique and around 2014 developed a mk2 version with smoother upper MF response and better breakup attenuation. This version went into the Reference in 2014 and then into the mk2 versions of R-series and the LS50 META. Overall the approach is very effective and provides a smooth upper MF response with a response that's very easy to crossover.

For Blade META we took the decision to drop the nodal drive and use the cone neck decoupler even in Blade. Considering all the compromises, I'm very happy that this is the right decision to give us the best overall performance. Compared to the MF of the outgoing Blade MF driver the moving mass is much lower, efficiency is higher, we avoid peaking in the breakup region, the rear venting of the MF is much happier, the xmax is much higher (more than doubled), the new motor distortion is lower, we can easily incorporate the tweeter gap damper and the smaller coil gives us space for the decoupling chassis. The voice coil diameter (50mm) is enough to handle the power required in Blade META, the 75mm coil in the original Blade MF was determined by the nodal drive requirement and rather over specified in terms of power handling. In addition, the increased driver efficiency reduces the power handling requirement significantly. One of the major things that this allowed was a gentler high-pass on the midrange (because of the increased xmax on the new driver) and this allowed us to make a big directivity gain in the LM/MF crossover region.

Hopefully this brief message gives you a bit of an insight into the engineering reasons behind the decision.

Thanks,
Jack.

 

[BrokenEnglishGuy]

That's a quality post
Thanks Jack