[Wigand]

Ah this was from a paper from kef right ?

Edit: if not I can get them I think. Only think is that the tweeter cap is in some material again

[maty]

It is from a KEF document. Obviously they did not put the values

[Wigand]

Ok no problem; but having the schematic confirmed is great.
Will note them later. It’s great that the inductor values are on the coils

[mlundy57]

Interesting discussion but it doesn't actually address the OP's point that the Metas can sound like open baffle speakers.

Never having heard them I can't disagree with Steve G that they sound like OB, but I'm skeptical. I can see how they could sound more open than the original version but can't see how they could go all the way to sounding like OB speakers. With OB speakers, the back wave doesn't just go into the room and disappear. It adds time delayed reflections that create the open spacious sound of OB speakers. The Meta only has the back wave that wraps around the baffle to add reflections like any other box speaker. What I don't see is how the partial frequency range that wraps around the baffle of the Meta can create the same effect as the full frequency range firing directly back that OBs have.

I know Steve likes Maggies so he knows what OB sounds like. I wonder if he is actually saying he thinks the Metas sound just like full OB speakers or if he is using OB as a comparison point and saying the Metas come closer to the full OB sound than any other box speakers he has heard. If the latter, I'll take him at his word. If the former, I'd have to hear it for myself to believe it.

 

[mick wolfe]

I'm somewhat skeptical as well. For a similar investment aside from the labor of course, one would be far better off building the NX Studio Monitor. A true approach to an open baffle concept (in regard to the tweeter's location) and most assuredly much better xover components.

[Wigand]

Opened them again for the values; inductors are ,2 ,9 and 2,4 (ironcore) on the woofer and ,3 on the tweeter. To be honest for the caps someone would need to rip the thing apart what I will not do.
Sorry guys. Its going to be a wait for the t26sg lol
If someone has two of those please let me know haha

[Hobbsmeerkat]

One of the caps was 18uF, likely for the mid/bass circuit though.

But it looking at these pictures in the earlier post, it looks like the caps in the tweeter circuit are coated in some sort of foam/ material making them look like inductors. And appear to be 2uF and 5uF, at least for the original LS50.

As far as the open-baffle sound goes, I imagine it's down to their ability to image and soundstage, and their design should allow for that.

But I agree that I would have to hear them

[paolocaminiti]

Regarding the OP and OB sound. I've been wondering about the following for a while and would be cool to get other's opinions.

I remember somebody on diyaudio explaining that the inherent advantage of a driver in free air (or OB) is that it sees the same mechanical impedance against the air going both directions. Thus allowing the driver to track (follow symmetrically) the signal in both directions with less distortion. This as opposed to a boxed speaker where the driver moving inward is always fighting the internal cabinet pressure that varies with the driver playing signal and the volume (thus also the importance to match driver Q with room size/pressure in boxed speakers and average playing SPL).

The quality of symmetry seems important in tracking an oscillating signal, and alnico drivers are also said to sound more natural due to their more stable more symmetric magnetic field.

This in my mind would account more for OB sound then the usually mentioned absence of first box reflections/resonances. Of course the back wave reverb (a pleasant distortion) as well adds to the character and spaciousness but less so to the transparency and effortlessness.

I wonder if Kef actually achieved something on those lines to make the meta sound more "open" and transparent.

To validate the initial hypothesis I don't have much, but these graphs on Devialet SAM tech page (https://www.devialet.com/en-eu/expert-pro-sam-ready-speakers/spatial/hologram_m2_turbo/) show that a speaker like the old Spatialaudio M2 basically needs no correction from the DSP - an automated measure/correct system with a known signal - compared for example to the kef meta...

[paolocaminiti]

I'm surprised there is no opinion about this hypothesis on driver behaviour in OB vs boxed speakers, not even from GR people them self.

It's never cited as part of OB advantages, and if true it would be a major flaw of boxed designs.

Perhaps a bit of topic, cause could be not related with LS Meta behaviour at all, but still interesting for OB enthusiasts.

[mlundy57]

I'm surprised there is no opinion about this hypothesis on driver behaviour in OB vs boxed speakers, not even from GR people them self.

It's never cited as part of OB advantages, and if true it would be a major flaw of boxed designs.

Perhaps a bit of topic, cause could be not related with LS Meta behaviour at all, but still interesting for OB enthusiasts.

Sounds potentially plausible but not being an engineer I don't have the knowledge to form an opinion

[Wigand]

Found this pretty interesting; the cap on the Tw is actually a claritycap CSA 4,7uf
The two on the woofer are 18 and 30 elektrolytic. Theres definately some room.

[Wigand]

[S Clark]

A friend brought his Kef LS50's by to compare to my speakers a couple of years ago.  We compared to my X-Statics.  The KEF were warmer, less detailed, and had thinner bass.  I wasn't impressed, and I certainly wouldn't say "open baffle" sound.  We didn't bother to put them in my big room to compare to my LS-9's. 
My friend has moved on to other speakers.  The Meta's may be a different beast entirely. 

[Hobbsmeerkat]

Reviving this thread cuz we just got a single LS50 Meta in a couple days ago.



Should be interesting to see how it measure and what we end up doing with them. It'll be a little time before we can get to them since there are a few other speakers in front of it.

But It feels reallt solid, knocking on the cabinet shows almost no ringing.

[Wigand]

Uh nice; will Danny make a Video about them?

[Hobbsmeerkat]

Uh nice; will Danny make a Video about them?

Yeah, he is likely pretty short and sweet though. Were not going to upgrade them, they actually measure quite well, and are built like a tank.
Plus getting the crossovers out to swap out the electrolytic caps means permanent removal as they are glued to pegs. Plus it would require an external crossover if we did offer an upgrade for them. Just not practical.

[Danny Richie]

Uh nice; will Danny make a Video about them?

I did.

[Saturn94]

I did.

Link?

[Hobbsmeerkat]

It's not up yet

[Saturn94]

It's not up yet

Thanks.