Endgame passive bookshelf shootout: KEF Reference 1 Meta vs. Ascilab S6B

[Goldhamster916]

I have listened to the LS50 Meta vs the R3 Meta and I want to love the R3 Meta, but when listening to music, the goddamn LS 50 Meta wins every time. Since, you already own LS 50 Meta and listen to low volumes (75db or less), then I don't believe that there is much more to be had than the LS 50 Meta.

I agree, I also compared them to the R3 meta and I preferred the LS50 meta in all music without Heavy bass. I think the curved nature of the baffle which reduces diffraction and the true point source gives them the edge. When played within its limit they sounded as least as good as the reference 5 (non meta), I had them both for several months side by side. I do think ls50 meta plus well integrated subwoofer is some of the best purchases you can make in audio.

Blades are effectively full range speakers - 30hz onwards .

kef would not have gone through the trouble for designing super small subs directly behind the coaxial drivers if it didnt make any difference.
There was a thread here that was gushing about the unique blade sound. cant find it now :/

i listened to them and they are indeed the best sounding speakers I have ever heard and I heard the reference 5, Dutch and Dutch 8C and Genelec the ones. However for my small room they are kind of wasted.

 

[Goldhamster916]

The Reference 1 and the S6B are also full range in a 20-25 m2 room.

The Blades also use a 5.25" woofer, of which the centre doesn't contribute to the sound emitted. While it is undoubtedly a superb driver, it cannot produce mid-bass at the SPL levels required for the larger rooms this speaker is also going to be placed in. If the crossover was placed at 80 Hz, the placement of the side woofers in the Blades matter because they are crossed much higher than a subwoofer would be.

Not to mention that replicating the placement of the Blades woofers would be impossible due to the depth of the bookshelf itself.

To be frank, while the concept of a source point is very good in theory, I think this only holds up from the lower mids or the upper bass, below that the location of the emission points of the bass relative to the room are more important than their location relative to the emission points of the upper frequencies.

As I mentioned earlier, if you absolutely wanted very high SPL capabilities, then the Reference 1 and the S6B are both very capable of producing mid-bass at an ear-splitting level and crossing at 80 Hz is the most reasonable thing to do, especially if you plan to go the two sub route anyway. Half-assing the replication of a concept and doing it outside its optimal range of applicability isn't a terrible idea.

You really think the midrange woofer of the blade cant handle the 450-2800hz range it operates in?
If I look at the distortion in that area it’s really low even at 96db. I listened to them in a roughly 50qm room, played very challenging electronic music to uncomfortable levels and there was no signs of stress at all.

 

[kharan]

You really think the midrange woofer of the blade cant handle the 450-2800hz range it operates in?
If I look at the distortion in that area it’s really low even at 96db. I listened to them in a roughly 50qm room, played very challenging electronic music to uncomfortable levels and there was no signs of stress at all.

I don't understand your question, mid-bass is 60-120 Hz, maybe 200 Hz if you don't have a specific upper bass range. So yes, I'm saying that the Kef Blade's driver can't handle high SPL mid-bass.

And Kef doesn't make them handle mid-bass at all, 450 Hz is definitely midrange.

 

[Goldhamster916]

In my experience imaging is related more to good pair matching in speakers and how much direct sound you get to listening position. So Kef could have better imaging bcouse narrower dispersion compared to s6b. Kef is about +-50 degrees hor compared to ascilabs +-60/70 so there is a big difference in reverberated sound. My diy speakers are constant +-45 degrees and imaging is prob best i have heard in my room.

Thank you!

My side walls are roughly 1 meter from each speaker and my listening position is 2m from both, I am still debating if I rather want a more narrow or wider dispersion. When listening to the LS50M whixh have similar radiation than the reference 1 I sometimes wonder if a little bit more room ambience would be nice.

 

[Goldhamster916]

I don't understand your question, mid-bass is 60-120 Hz, maybe 200 Hz if you don't have a specific upper bass range. So yes, I'm saying that the Kef Blade's driver can't handle high SPL mid-bass.

And Kef doesn't make them handle mid-bass at all, 450 Hz is definitely midrange.

But they have combined 8 relatively long excursion 6.5 inch drivers on their side. The blade 1 has 8 9 inch drivers. You don’t think that’s enough?

 

[kharan]

But they have combined 8 6.5 inch drivers on their side. The blade 1 has 8 9 inch drivers. You don’t think that’s enough?

I suggest you read my first post about the Blades carefully again. I specifically said that the 5.25" mid-range driver of the Kef Blades couldn't handle high SPL mid-bass.

 

[Goldhamster916]

I suggest you read my first post about the Blades carefully again. I specifically said that the 5.25" mid-range driver of the Kef Blades couldn't handle high SPL mid-bass.

But it isn’t playing at that range (as far as passive designs go). It is crossed over at 450hz to the LF drivers on the side. Sorry if I misunderstand what you are saying.

 

[kharan]

But it isn’t playing at that range (as far as passive designs go). It is crossed over at 450hz to the LF drivers on the side. Sorry if I misunderstand what you are saying.

I'm saying that the front driver of the Blades can't handle mid-bass. Thus, Kef makes the side woofers handle mid-bass and even lower mids.

If the side woofers (of the Blades) only handled sub-bass, i.e. lower than 80 or 60 Hz, then their position wouldn't matter. But since the side woofers handle higher frequencies like lower mids, then their position and the geometry of the cabinet matter.

This is different from your situation, where the bookshelves would handle mid-bass and the subwoofers would handle sub-bass.

 

[Maxim-ICOM]

Hello everyone,

which one, is in your opinion, the overall better speaker and why? Which one would you pick?



KEF Reference 1 Meta: ported 3 way design (coaxial plus woofer)
dimensions: 44x20x42cm

Ascilab S6B: 2 way using purify woofer and tweeter plus passive radiators
dimensions: 40x22x30cm

---->Reference 1 is quite a bit larger


I could not find any compression data for the S6B.

Unfortunately there is currently no option to demo the S6B in europe. I heard the reference 1 multiple times and it sounded great to me.
Since i intend to keep these for life (fingers crossed) and will probably move a lot in the future i make the decision quite independent of the room. I value engeenering and performance even beyond audible benefits.
Money is not a concern, i just want the best passive bookshelf i can find. if you can think of any better passive bookshelfs let me know.

I am curious about your input.

thanks in advance for taking your time to respond!

Indeed with just looking on the graphs you cant tell which speaker sounds better.
An example here - 1m gated measurements for 2 speakers, both measured quite nice and fit to almost +-1.5dB, but you cannot tell which one you will like.
Except frequency response and distortion there are many factors what affect the sound.

What is your room size, proportions and equipment?

 

[Goldhamster916]

I'm saying that the front driver of the Blades can't handle mid-bass. Thus, Kef makes the side woofers handle mid-bass and even lower mids.

If the side woofers (of the Blades) only handled sub-bass, i.e. lower than 80 or 60 Hz, then their position wouldn't matter. But since the side woofers handle higher frequencies like lower mids, then their position and the geometry of the cabinet matter.

This is different from your situation, where the bookshelves would handle mid-bass and the subwoofers would handle sub-bass.

I get it now, I thought you were saying the blades dont have enough mid bass output. Yes you are right, there wouldn‘t be a ,,point source“ benefit of having a subwoofer behind the speakers when crossed over at 80hz. Sorry for the long conversation

 

[Jonazkur]

Thank you!

My side walls are roughly 1 meter from each speaker and my listening position is 2m from both, I am still debating if I rather want a more narrow or wider dispersion. When listening to the LS50M whixh have similar radiation than the reference 1 I sometimes wonder if a little bit more room ambience would be nice.

Your listening distance is pretty short so i would personally take S6B. Wider dispersion is better for shorter distances.

 

[Goldhamster916]

Indeed with just looking on the graphs you cant tell which speaker sounds better.
An example here - 1m gated measurements for 2 speakers, both measured quite nice and fit to almost +-1.5dB, but you cannot tell which one you will like.
Except frequency response and distortion there are many factors what affect the sound.

View attachment 511663

What is your room size, proportions and equipment?

My room is 4x3,5 meters, they would have roughly 1 meter on each side to the side walls and listening distance would be 2.5 meters roughly. However since I will probably move a lot in the next years I don’t want to make the decision based on the current room and rather get the best performance I can. All I know is that listening distance will probably never be more than 2 meters since I also use them as main speakers of a surround system and I don’t want to sit further than 2 meters from the TV.

 

[Goldhamster916]

Your listening distance is pretty short so i would personally take S6B. Wider dispersion is better for shorter distances.

That is a good argument and I think you are right.

 

[Maxim-ICOM]

My room is 4x3,5 meters, they would have roughly 1 meter on each side to the side walls and listening distance would be 2.5 meters roughly. However since I will probably move a lot in the next years I don’t want to make the decision based on the current room and rather get the best performance I can. All I know is that listening distance will probably never be more than 2 meters since I also use them as main speakers of a surround system and I don’t want to sit further than 2 meters from the TV.

The room is not big and 2-way with 6.5" woofer will fit fine there - you'll get 45Hz -3dB, your small room will add support on bass and you will not feel lack of bass. You'll get same with Kef Ref1 or Purifi 6.5-based speakers.
Sure, if you want a kick in chest you need to go to higher caliber for woofer.

Kef Ref 1: while it measures well I cannot listen them long - there is something what start to irritate my ears.

Purifi PTT6.5W Alu based speakers: they are nice drivers, but you cant fool physics - mms is more then twice higher if compared to SB Satori MW16 drivers, the midrange will not be that good and detailed, while Purifi's bass and power handling will be better then Satori MW16. If you for "soundpressure", and mostly listen to pop where you need to feel base then Purifi-based speakers is what you need.

If you want retrieve more music details and get a speaker what will please you I suggest custom builds based on SB Satori drivers.
With your budget you may go with re-workerd SB ARA with Beryllium tweeter and MW16TX-4 Textreme woofer.
SB Acoustics ARA Beryllium dome Textreme Light Edition - FineTuning by StereoArt
or
SB Acoustics ARA Beryllium dome Textreme TOP Edition - FineTuning by StereoArt
TOP edition is my favourite bookshelf and can compete with many from crazy-priced high-end 2-ways of a same size.
Will cost less then Kefs or Ascilabs, will measure same or better, but definely will be more interesting to listen. Drivers and internal components are unbeatable top-level products.

 

[mglobe]

FWIW I listen to my Reference 1 Metas towed out 30degs. I.e pointing straight out into the room. 9’ equilateral triangle. Imaging is superb and no fatigue at all.

 

[berjine]

Purifi PTT6.5W Alu based speakers: they are nice drivers, but you cant fool physics - mms is more then twice higher if compared to SB Satori MW16 drivers, the midrange will not be that good and detailed, while Purifi's bass and power handling will be better then Satori MW16. If you for "soundpressure", and mostly listen to pop where you need to feel base then Purifi-based speakers is what you need.

Mms is higher but keep in mind that the xover is only 1kHz in the S6B, so no problem at all

 

[Lars Risbo]

Purifi PTT6.5W Alu based speakers: they are nice drivers, but you cant fool physics - mms is more then twice higher if compared to SB Satori MW16 drivers, the midrange will not be that good and detailed, while Purifi's bass and power handling will be better then Satori MW16. If you for "soundpressure", and mostly listen to pop where you need to feel base then Purifi-based speakers is what you need.

Mms: has no influence on the midrange - increasing Mms lowers F3 at the expense of lower sensitivt but does not affect the midrange. it’s a very common misunderstanding that we addressed in a blog post (not sure if link are allowed here)

 

[kharan]

Is midrange incredibly transparent and quick with headphones? To my ears, it's not, and mms is incredibly low with those drivers.

 

[Lars Risbo]

The room is not big and 2-way with 6.5" woofer will fit fine there - you'll get 45Hz -3dB, your small room will add support on bass and you will not feel lack of bass. You'll get same with Kef Ref1 or Purifi 6.5-based speakers.

a 6.5” alu cone PTT woofer can reach an F3 of 33Hz.

 

[Goldhamster916]

a 6.5” alu cone PTT woofer can reach an F3 of 33Hz.

Yes and the purify driver has about 5 db more output around 30hz at lower distortion.


@mglobe i really like that finish on the reference 1. if my room wouldn’t have a black white scheme going on that would be my favorite.