Blade is a midrange / high range coax with side mounted woofers, Visaton do not have a coax so i have taken an MTM, the interesting part of the directivity index diagram is related to the side mounted woofers
I post here the variation with one B100 as fullrange as better simulation of what the Blade coax will do - it gets even worse with the directivity plot
the Blade comes with a passive crossover, no chance to play around with delay or FIR filters, this has been done with the LS 60 that probably do not have the directivity plot screwed between 200 and 500 Hz, see also the SPL change in the estimated energy frequency response on axis, side woofers works in my eyes only up to 200 Hz with this shape of enclosure
I post here the variation with one B100 as fullrange as better simulation of what the Blade coax will do - it gets even worse with the directivity plot
the Blade comes with a passive crossover, no chance to play around with delay or FIR filters, this has been done with the LS 60 that probably do not have the directivity plot screwed between 200 and 500 Hz, see also the SPL change in the estimated energy frequency response on axis, side woofers works in my eyes only up to 200 Hz with this shape of enclosure
I'm not convinced cardioid is only beneficial in a small room. Why wouldn't you want less room interaction in the upper bass / low mid and a more even DI in every room?
We've got measurements of what it will do. https://www.erinsaudiocorner.com/loudspeakers/kef_blade2_meta/
How can they not be more accurate than your predictions with the sims?
KEF Blade 2 meta vs Reference 5 meta?…..which is better?
Here my answer comparing with my sim
A ) Blade clone graphs
B ) Same thing with front mounted woofer drive units, well looks a little bit like the Reference 7 and not the Reference 5
just the position of the woofer makes the difference - i don't care about Erin's corner - i want to see the difference between front mount and side mount of exactly the same drivers in the same enclosure shape
here the best directivity representation that you don't have with Erin at all first graph for A ) second graph for B )
hope it helps, Stefano
P.S.: executive summary - the KEF Blade is a design thing, technically speaking front mounted woofers make less trouble
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For me, the charm of the blade is in the horizontal and vertical directivity (quite identical). And you can shove aside the measurements by Erin, but the directivity index in real life looks way better than your sim does. Not for one minute do I consider the Blade a design thing. Even the shape of it is functional.
If your simulated DI does not look like what Erin measured, something must be off on your side. Can't see it any other way. You may not care about what Erin does and that's fine. But the Klippel measurements shown by him are the closest thing we have to anechoic measurements and are deemed trustworthy.
The slow rising DI (without the sudden bumps like yours) makes it enough for me to take notice.
Combine it with the linearity and the smooth frequency response, but above all, the controlled directivity both horizontally and vertically is what it makes more than just a "design thing".
In all honesty, I would not want to build any speaker with the DI curves you show here. But that's just my preference. I like speakers that can work well in a room. But you need the right room to make it work. The Blades are not for me.
If your simulated DI does not look like what Erin measured, something must be off on your side. Can't see it any other way. You may not care about what Erin does and that's fine. But the Klippel measurements shown by him are the closest thing we have to anechoic measurements and are deemed trustworthy.
The slow rising DI (without the sudden bumps like yours) makes it enough for me to take notice.
Combine it with the linearity and the smooth frequency response, but above all, the controlled directivity both horizontally and vertically is what it makes more than just a "design thing".
In all honesty, I would not want to build any speaker with the DI curves you show here. But that's just my preference. I like speakers that can work well in a room. But you need the right room to make it work. The Blades are not for me.
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If the enclosure is built well, the offset cancellation from opposed woofers is negligible at best. If we were talking large sub drivers with long stroke motors, I’d be more inclined to get on board.
Again, the narrowed vertical directivity of a line source or wwmtww of wwcww isn’t ’problematic’…..in fact i find it beneficial. With 45-55 inches to the ceiling first reflection, distance and the absorption coefficient of dry wall takes care of the rest and an area rug manages the floor bounce just fine. I WANT the sound to compliment the room and vice versa…..if I wanted an illusion , I’ll listen through my Audeze phones.
As for Erin and his sighted listening subjectivity (🤣)…….different strokes for different folks. I found his latest comparison of the new Dayton speaker at $800 against the $22k blade interesting 🤦♂️
Bottom line is most true lovers of music and performance could care less about measurements when choosing a piece of gear…………the connection comes first.
Again, the narrowed vertical directivity of a line source or wwmtww of wwcww isn’t ’problematic’…..in fact i find it beneficial. With 45-55 inches to the ceiling first reflection, distance and the absorption coefficient of dry wall takes care of the rest and an area rug manages the floor bounce just fine. I WANT the sound to compliment the room and vice versa…..if I wanted an illusion , I’ll listen through my Audeze phones.
As for Erin and his sighted listening subjectivity (🤣)…….different strokes for different folks. I found his latest comparison of the new Dayton speaker at $800 against the $22k blade interesting 🤦♂️
Bottom line is most true lovers of music and performance could care less about measurements when choosing a piece of gear…………the connection comes first.
KEF Blade 2 Meta, non-normalised data.
with thanks to @bikinpunk
Reference:
https://www.erinsaudiocorner.com/loudspeakers/kef_blade2_meta/
more to come....
with thanks to @bikinpunk
Reference:
https://www.erinsaudiocorner.com/loudspeakers/kef_blade2_meta/
more to come....
I believe the energy at frequencies that drive cabinet structural modes is probably the most important in regards to the force cancelation. On a floor-standing speaker I'd guess there are a few panel modes in the range <450Hz.
If you want to do front mounted woofers then go for it
I was only joining the discussion on a basis of understanding the pros and cons of each layout. I do agree that narrowing vertical directivity can be beneficial, but the directivity ideally should transition smoothly with frequency and I'm not sure how ideal it is to jump from significantly spaced vertical woofers to a point source. If we say the wavelengths are large enough <450 Hz not to matter, then it also would not matter if we place the woofers on the side to gain force cancellation Neither way is wrong!It wasn't a comparison-based review. It was a review of a speaker which I did also listen to against a known (neutral, impeccable DI and extremely low distortion) speaker. To better give the audience an idea of what differences I heard and how those relate to the data. But to frame it the way you did leads one to believe the entire review was done as a comparison; it was just the listening portion done this way. I want to clear that up.
Some people don't like subjectivity. Some people don't like data. I do both. And I enjoy both. There's enough animosity in this world; I don't see why people need to bring it to speakers.
All this said, if I had the time, I'd seriously consider DIY'ing my own blade speaker. Obviously having to take some shortcuts when it comes to the speaker aesthetic because my skills are low when it comes to fabrication as well as finding a suitable concentric replacement given so many of the DIY brands have terrible diffraction elements thanks to poor tweeter/midrange termination. But - on the whole - I think the pointsource idea is the most logical. Doesn't mean other designs don't sound fantastic as well. But it just makes sense to me to do what KEF has done with their Blade design.
Hi @mayhem,
if you want to get out the most of your 4 woofers each side (4 times more expensive than 1 woofer, but 10 dB more max SPL)
take this placement, but it do not look like a Blade clone anymore
you need a Hypex FA123 with 3 channels, the back fire woofers need a separate channel and the front woofers and here the FR instead of the C 1ms delay
no directivity bumps for f > 50 Hz, slightly dipole characteristic in the crossover region to the FR
if you want to get out the most of your 4 woofers each side (4 times more expensive than 1 woofer, but 10 dB more max SPL)
take this placement, but it do not look like a Blade clone anymore
you need a Hypex FA123 with 3 channels, the back fire woofers need a separate channel and the front woofers and here the FR instead of the C 1ms delay
no directivity bumps for f > 50 Hz, slightly dipole characteristic in the crossover region to the FR
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you have 6 dB plus for the same amplifier output power, but 4 drive units driven with 2 separate power amps have doubled power output when the max SPL limiting factor is the amp and not the drive unit - 2 chassis 8 ohm parallel 4 ohm impedance -> more max power from amp - all together round about 10 db
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i meant the active speaker system with the FA123 amplifier and speakers max SPL combined
it's definition, the 4 drive units compared to one drive unit without the activation with the FA123 with 2 channels for the four speakers increase max SPL only 6 dB, thanks for your clarification
it's definition, the 4 drive units compared to one drive unit without the activation with the FA123 with 2 channels for the four speakers increase max SPL only 6 dB, thanks for your clarification
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yes……I’d agree on the point source alignment.…..I’m just not sure that the complex design of the Blade justifies the design choice over a conventional forward firing WWCWW.
The Blade has it‘s placement limitations for sure……side wall reflections have to be considered and as such, given the size of the speaker and the distance required to effectively separate two of em, you’ve now got a soundstage wall of a MINIMUM of 15 ft or 3 meters. These dimensions are scarce in the realm of average folk…..and less likely to be acceptably consumed with 22k speakers by the family unit. I’m a pragmatist….I’ve stated it often….and I believe most DIY folks come from a pragmatic position……build something sensible on all fronts….meets their needs, environment and pockets.
I think KEF brought the Blade to market to find a common ground…..hi design meets high function. The additional $12-15k might just be all high design…..i‘m working this out here and in my head. Double blind in the same room the R11 Meta vs the Blade?……..who prefers what? And then quantified…….$18,000 left to spare?………seems even the mildly pragmatic might appreciate the alternative.
High end audio is anything BUT pragmatic…..this is self evident and needs no further dissection.……the mantra goes insanely beyond diminishing returns. Could a much more cost effective fwd firing WWCWW using the Uni Q compete with the Blade on a purely unsighted subjective battlefield?…….that’s the intent of this thread. Given I actually listen to music for a living (half of what I do to survive) and instigated such battles, I’m pretty confident it’s possible.…..subjectively without institutional interference is an eye opening experience.