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Kef Reference 1 vs LS50M w subs

hardisj

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Could you please share your measurements of your reference 1 meta? I would love to compare the reference 1 meta and the r3

They'll be public in two days when the video and review goes live. I haven't gotten the review on my website yet. Though, I have already posted the graphs on my Patreon page.
 
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envydd

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They'll be public in two days when the video and review goes live. I haven't gotten the review on my website yet. Though, I have already posted the graphs on my Patreon page.
Thank you. Will look for it when it’s live.
 

exm

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I can say that I compared the R2c with the Reference 2C and the difference is night and day between these two. But then again, the center is mostly used for dialogue and that's where the Reference Uni-Q tweeter shines. I doubt if I replace my R900s (I also used to own the R11, but I like the R900 better. Different story) with the Reference 3 that the difference would be as much as the center upgrade.
 

bo_knows

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FYI...Erin's YouTube review of KEF reference 1 meta is up and running.
Erin did a great job as always but this episode was special (to me). :)
 
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Darvis

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FYI...Erin's YouTube review of KEF reference 1 meta is up and running.
Erin did a great job as always but this episode was special (to me). :)
He's easily the best reviewer out there. And he looks like a genuine and sweet dude to boot.
 

Tangband

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This is what happens with a uniQ driver if they are driven fullrange .


3B9684BD-5390-403B-BF6C-6CF467D23B94.png


At +-3mm movement of the cone, you get a 8 dB difference at 7,5 KHz in frequency response. This happens if you play real music containing deep bass . The cause is the cone acting as a variable waveguide for the tweeter when its moving .
This can not be seen with a sine sweep.

To solve this problem , a uniQ driver or any other coaxial driver has to be HP filtered at about 300 Hz . This is done in Kef reference 1.

So the ls50M is compromised because of this , the problem gets smaller if they are HP filtered at 80 Hz .
 
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ernestcarl

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a uniQ driver or any other coaxial driver has to be HP filtered at about 300 Hz

Just to clarify: not all coax speakers have to be high-passed that high! :eek:

Just as an example, Fulcrum Acoustic's RX699 uses a horn waveguide which avoids this kind of response modulation -- but, at the expense of some off-axis response linearity, diffraction and narrowing -- at very high SPLs:


I've been eyeing this model or the RX599 to substitute/replace my single driver Fostex 6301 (SPL limited) which I'm currently using mostly as a center fill to better anchor vocals. Distance is a bit long at around 3m -- so it does not have enough juice as a center channel at very loud listening volumes -- moreover, it'll have to sit behind an acoustically transparent screen so any extra HF boosting capability is desirable. Like all of Fulcrum's coaxes, however, it needs FIR filtering.
 

HarmonicTHD

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This is what happens with a uniQ driver if they are driven fullrange .


View attachment 238928

At +-3mm movement of the cone, you get a 8 dB difference at 7,5 KHz in frequency response. This happens if you play real music containing deep bass . The cause is the cone acting as a variable waveguide for the tweeter when its moving .
This can not be seen with a sine sweep.

To solve this problem , a uniQ driver or any other coaxial driver has to be HP filtered at about 300 Hz . This is done in Kef reference 1.

So the ls50M is compromised because of this , the problem gets smaller if they are HP filtered at 80 Hz .
These are all different drivers between the Q the LS and the Reference. But in essence it is correct that one has to high pass the drivers.
 

Daka

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This is what happens with a uniQ driver if they are driven fullrange .


View attachment 238928

At +-3mm movement of the cone, you get a 8 dB difference at 7,5 KHz in frequency response. This happens if you play real music containing deep bass . The cause is the cone acting as a variable waveguide for the tweeter when its moving .
This can not be seen with a sine sweep.

To solve this problem , a uniQ driver or any other coaxial driver has to be HP filtered at about 300 Hz . This is done in Kef reference 1.

So the ls50M is compromised because of this , the problem gets smaller if they are HP filtered at 80 Hz .
R series are crossed at 400Hz, reference 450. I wouldn’t say it’s that high done because of Uniq causing distortion in high freq but higher distortion at higher volumes in mid base (under 400Hz). I would suspect up to 80Hz-100Hz it’s a noticeable distortion in higher frequencies, I can hear it, but not all the way to 300hz - that would only be apparent at really high volume and would be mid base distortion mainly.
More over with ls50 meta, someone measured at high volume distortion takes off from around 150Hz so if you would cross it at that point majority of distortion would be gone.
 
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