Yes, but then again I find most speakers sibilant. What it did with brass annoyed me more though, the way both timbre and decay was seemingly compromised. I felt like it both masked the harmonics (ie. timbre) of brass, as well as making the leading edge mask the trailing edge in time. I think KEF suppressed the cone breakup so I would not attribute it to the breakup, just the overall transition between midwoofer and driver.
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KEF's new Metamaterial Absorption Technology
- Thread starter kaka89
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Yes, but then again I find most speakers sibilant. What it did with brass annoyed me more though, the way both timbre and decay was seemingly compromised. I felt like it both masked the harmonics (ie. timbre) of brass, as well as making the leading edge mask the trailing edge in time. I think KEF suppressed the cone breakup so I would not attribute it to the breakup, just the overall transition between midwoofer and driver.
The peak around 2k is responsible for this, I had the same issue with them but after smoothing that out with a few PEQ filters, I could listen as long as I wanted and they were very smooth. Most modern amps are ruler flat so it's not surprising that different amps couldn't tame them, I find PEQ to be a much better tool at taming problems like that.
I don't know what is with that sawtooth at 2kHz but i think it is too subtle on LS50Meta to be noticed. As for 1.3kHz, it is clearly visible at 75 degrees off axis in both LS50 and LS50Meta. Most probable cause is suspension resonance. Here are mine on and off axis measurements of LS50 with reworked crossover. Green is 80 degrees. Resonance at 1.3kHz and at 2kHz are very visible. Pay attention that this is 1dB grid resolution and 20dB grid height, so highly revealing.
These measurements are done in room so not the best resolution, but i think that it is revealing enough above 500Hz to be able to spot the aberations.
0,10,20
20,40,50
More on that HERE.
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Never heard that sibilance through my LS50W. If anything, they excel at the female and male voices. Please keep in mind this is not my main system but more for the background music in my living room/lounge. I feed them via my laptop and youtube signal which is apparently cut off after 16khz. The signal may not have a high enough resolution for me to notice.
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thewas
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The LS50 show 2 humps around 2 and 5 kHz which can make them too forward and shouty sounding, see also https://www.audiosciencereview.com/...helf-speaker-review.11144/page-24#post-573976
But just with a little bit of EQ they transform to something fantastic which when positioned well has impressed me more than any other of my more then dozen loudspeaker pairs.
But just with a little bit of EQ they transform to something fantastic which when positioned well has impressed me more than any other of my more then dozen loudspeaker pairs.
Because the LS50W fixed most of it. The problems are limited to the first-gen LS50 passive.
I do have both since a week ago, and although they still are in break-in mode (I did listen more bass in the dealer's listening room), I think the Meta is a clear, I would say even big improvement over the original (which I love). The sound signature is the same, but it is a much more refined speaker, imho.
Main differences: a little more laid-back sound, much deeper soundstage, less in-your-face sound, big improvement of the already impressive imaging (detail and stability); the speaker "disappears" even more than the original (it is just shocking in this area, almost nothing I've heard comes close), more detail retrieval, gone is a slight harshness (like in some metal winds) the original has.
Still needs a subwoofer, although there is a little more resonant bass (it is not deeper, but less 'dry', ie: a vibrating acoustic bass string decay is better heard, imho, although this is a minor difference yet). That said, I've been listening without a SW, because I sold mine (kube12b) for an upgrade to a REL, still not here.
Both are used as monitors, very far apart from rear and side walls, in a triangle of 2.2-2.5 mts with the back wall far apart, in a 45sqm room. I found the Metas allow to enlarge the size of that triangle without a hole in the middle, as it happened with the originals.
Extremely happy with the upgrade; this is a fantastic speaker, much better than anything I've heard near its price range. The old one went to my second system. And, sorry for my rusty english
According the Canadian Research measurements, this is the Dif between the Meta (dark red), and the original LS50 (green). Main difference is a slightly flatter FR, and more obvious, a more educated behavior in the 1.8-3.6 Khz octave, that perhaps correlates with part of the description of differences of my previous post.
There is a filter that Kef claims necessary to compensate the higher sensitivity in the upper midrange:
I would like to implement an active crossover in the digital domain.
Does anyone know if it is possible to measure, in a regular room, with reasonably accuracy, the response of the drivers?
I have a USB Dayton microphone and absorbers that I could place strategically for such measurements.
The idea is to find the ideal parameters for such upper midrange filter and also for the baffle step compensation.
I would like to implement an active crossover in the digital domain.
Does anyone know if it is possible to measure, in a regular room, with reasonably accuracy, the response of the drivers?
I have a USB Dayton microphone and absorbers that I could place strategically for such measurements.
The idea is to find the ideal parameters for such upper midrange filter and also for the baffle step compensation.
Not sure about a room, but if you have a large open area like a backyard or field you can try to measure the driver by keeping the mic very close to it and gating the response ?
Unfortunately there is too much noise where I live.
the FR looks smuch better in the all important upper bass and mid range region to my eyes, although the bass is still really poor... likely the area eaten up by the tweeter makes it essentially a 3-4" woofer?
You are absolutely right. Radiating area is reduced vs pure midwoofers of similar diameter as the tweeter + its attachments are necessarily held stationary and decoupled from the rest of the cone. Erin @hardisj showed this best in photos from his review of a similar KEF driver.
Woofer at rest:
Woofer out:
Woofer in:
So it's really a donut-shaped segment that's radiating, vs the full circle of a dedicated midwoofer.
Yea, I think this is the driver used in the Q100 and my X300A which now went to my living room for TV and movies, it actually still sounded ok when I place them minimum distance to the wall to utilize the wall bass boost, but once having comparison it's no where near to what the 8030 can do with nominal 5" woofers
Count Arthur
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Isn't it the case that there's no real standard for measuring driver diameters?
Some measure to the bolt circle diameter, some to the outside of the frame, etc.. You would think that there would be some sort of standard, perhaps the surface area of the radiating/active part of the driver, something like that. However, even that wouldn't really tell you much about it's sonic capabilities, as that would vary according to how far the cone can travel back and forth.
In the end, I guess the physical measurements of a driver only really tells you how big the hole in the baffle needs to be.
Some measure to the bolt circle diameter, some to the outside of the frame, etc.. You would think that there would be some sort of standard, perhaps the surface area of the radiating/active part of the driver, something like that. However, even that wouldn't really tell you much about it's sonic capabilities, as that would vary according to how far the cone can travel back and forth.
In the end, I guess the physical measurements of a driver only really tells you how big the hole in the baffle needs to be.
That's why we want to look at datasheets of individidual drivers, if available! Not available for UniQ so one must use a ruler...
Simulation programs utilize the real "acoustic" diameter, which is measured from middlepoint of surround roll (typically highest point of single roll) If the driver has solid center (phase plug or coaxial tweeter), it's area must be reduced while diameter stays same. Depth and profie of cone is not so important and not used in simulations except some AKABAK etc. sims.
Diameter says a lot of dispersion, and area x excursion max tells about spl capacity.
Simulation programs utilize the real "acoustic" diameter, which is measured from middlepoint of surround roll (typically highest point of single roll) If the driver has solid center (phase plug or coaxial tweeter), it's area must be reduced while diameter stays same. Depth and profie of cone is not so important and not used in simulations except some AKABAK etc. sims.
Diameter says a lot of dispersion, and area x excursion max tells about spl capacity.
thewas
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The good thing is that the inner 5 centimetres of diameter not contributing to the bass while being almost the half to the active woofer diameter (from middle to middle of the surround approx. 11 centimetres diameter) count much less to the surface due to the quadratic law, so the Uni-Q has approximately the same surface of a normal woofer of 10 centimeters active woofer diameter) so its still in point of active surface closer to a typical nominal 5" woofer than to a 4" one. (11^2-5^2=121-25=96 vs 10^2=100)
Funnily I also always thought the lost surface would be higher till now.
Dont' many woofers put a dust-cap around the same size - so is the ls50 woofer that much smaller ? I prefer the R3 due to having a dedicated bass drivers due to which the wave guide formed by the mid does not change position as much as the LS50, but a Sub could achieve the same effect.
Dustcaps are glued to the cone, so they move along with it.
"Phase plug" is used in some midranges and woofers. It is screwed to the magnet/frame and doesn't move with the cone. This kind of drivers shouldn't be used in a closed box!
"Phase plug" is used in some midranges and woofers. It is screwed to the magnet/frame and doesn't move with the cone. This kind of drivers shouldn't be used in a closed box!
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