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Kef ls50 meta demo experience

That probably is a good rule of thumb. In the examples I provided, when using a low output impedance amplifier, with a passive crossover the DF is 3.50 and is 70.17 without. The passive crossover setup has a DF well below 20 and the all active setup has a DF well above 20, and thus should reflect a visible change in the transient signals.
Also, much depends on the actual impedance of the low pass filter connected to the woofer. My speakers are 3-way and were crossed over around 220Hz or so, with a 3rd order filter. The resistance of the inductors is fairly high, together 1.6 ohms.

If you take a 2-way speaker with a higher crossover frequency, perhaps 1st or 2nd order, the resistance likely will be lower. Thus, the negative impact of the crossover on the damping factor will be less. Using my examples of an amplifier output impedance of 0.02 ohms, a speaker cable resistance of 0.04 ohms and a 4.15 ohm driver, the total DCR of the filter inductors can be as high as 0.15 ohms (ignoring core losses) while still achieving a damping factor over 20. Again, this is just an estimate as the actual impedance is frequency dependent.
 
Also, much depends on the actual impedance of the low pass filter connected to the woofer. My speakers are 3-way and were crossed over around 220Hz or so, with a 3rd order filter. The resistance of the inductors is fairly high, together 1.6 ohms.

If you take a 2-way speaker with a higher crossover frequency, perhaps 1st or 2nd order, the resistance likely will be lower. Thus, the negative impact of the crossover on the damping factor will be less. Using my examples of an amplifier output impedance of 0.02 ohms, a speaker cable resistance of 0.04 ohms and a 4.15 ohm driver, the total DCR of the filter inductors can be as high as 0.15 ohms (ignoring core losses) while still achieving a damping factor over 20. Again, this is just an estimate as the actual impedance is frequency dependent.

Oh, if the comparison involves an amplifier with a poor damping factor to begin with, it makes sense that a difference might be perceivable. However, this likely wouldn’t apply in most scenarios, as amplifiers typically have a sufficient damping factor -except for those intentionally designed otherwise.
 
Oh, if the comparison involves an amplifier with a poor damping factor to begin with, it makes sense that a difference might be perceivable. However, this likely wouldn’t apply in most scenarios, as amplifiers typically have a sufficient damping factor -except for those intentionally designed otherwise.
If you start with an amplifier that has a high output impedance, such as a tube amplifier, the calculations show that you will not be able to achieve a very good damping factor, even if you do remove the crossovers. In the example I used for the calculations, removing the crossover only changed the damping factor from 1.74 to 2.02.

In my case, my amplifier has a very low output impedance (oftentimes referred as damping factor, but wrongfully so in my opinion since that is only one piece of the puzzle). But, my Elac UBR62 speakers had relatively high resistance in series with the woofer due to the inductors that were used in the crossover's woofer low pass filter. The bass response sounded weak to me, even with a subwoofer handling the low bass and using Dirac Live. Removing the crossover, as well as plugging the ports, in my speakers improved the bass response. The woofer now is more dynamic, impactful. The calculations show why; the damping factor increased from 3.50 to 70.17 in the example I gave. (Side note: my actual damping factor is lower due to the long speaker cables I am running, now probably around 30).

With all that said, if you start with an amplifier that has a low output impedance, a speaker that has very low resistance on the inductors in series with the woofer, and low resistance speaker cables, then the damping factor should be adequate to achieve good bass.
 
Interesting. I had the LS50 Meta, before I sold them to my sister, which have totally different requirement than me - and room.
They are actually just a redesign of the original midrange driver, with a Z-flex suspension and a bit more X-max. So no wonder that it can't play any louder.
If you want floor standing 3-way SPL levels - cross it higher and place it on a "woofer-stand" like Genelec. I did that, and it should hopefully be no surprise, that you can't cheat physics ;)
https://audiosciencereview.com/foru...f-ls50-meta-review-speaker.25574/post-1780110
Now we added a subwoofer for her setup, since they still need extra bass, even though they are each placed in the upper corner of a smaller concrete room, where bass gets a little "boost".
 
If you want floor standing 3-way SPL levels - cross it higher and place it on a "woofer-stand" like Genelec. I did that, and it should hopefully be no surprise, that you can't cheat physics ;)
https://audiosciencereview.com/foru...f-ls50-meta-review-speaker.25574/post-1780110
did you remove the crossover or simply used an low pass via dsp?

With all that said, if you start with an amplifier that has a low output impedance, a speaker that has very low resistance on the inductors in series with the woofer, and low resistance speaker cables, then the damping factor should be adequate to achieve good bass.
Does this mean that an speaker with low impedance in the bass region (e.g. 3 Ohm) is for that reason better that a speaker with e.g. 8 ohm?
 
did you remove the crossover or simply used an low pass via dsp?
LP via DSP. I wanted them to stay vanilla, since there was a big chance for resale.
I ended up with the dedicated midrange version from the R3 instead. Nicer FR and higher sensitivity, which fits better to a 3 way project.

Maybe the lower distortion of the Meta, make for a lower cross-over = a bit better power response. But comparing the LS50 Meta with the dedicated midrange coax from the R3 none Meta - did not convince me that it was a problem, to cross the none Meta, at around 2200 Hz, still giving me a nice smooth transition between tweeter and midrange.
But I might sleep better at night.... and maybe it can be measured - if I some day get a hold of a set of dedicated midrange coax units, from a KEF R3 Meta or greater.
 
I also got the ls50 meta for my bedroom.
Well I was reading all these reviews about them being bass shy, so I thought they`ll be great for my bedroom. Never liked bass heavy speakers, or subwoofers even though I have one in my HT system.
Well lets say Ls50 are not bedroom speakers. First they need current, small amplifiers or what is typically used in a small room don`t make them shine.
I don`t even know why kef label them like 8 ohm speakers, probably they`re more like 6 or 4 ohm. I found a space for my old 33lb JVC, who drives them effortlessly.
Second they do a lot of bass in my room, unfortunately overblown bass, the maximum distance from the rear wall I can place is 30cm, so by manual I put the foam plugs, the outer ring.
They really measure these modern speakers, because once 1.5cm foam was inserted in the port the bass was way more controlled, and still there is plenty for what I like in my music. I was lucky I got these and not the R3 meta.
They do imagine very good, and are a bit rolled off in highs, at least compared to what I was using before, but I still have to try them on stands.
Just before you judge these speakers try a high current amplifier.
I know that the trend here is that amplifiers for low volumes sound the same, but from my experience, this is not the case.
Dacs are much more similar sounding than amplifiers, especially when driving low efficiency speakers.
 
Equalize as much as you want, it want change a normal amplifier to a good one.
These speakers at moderate volumes, play like you have 3 or 4 speakers in front of you, and they make a lot of bass. I accidentally have unplugged one of the speakers, and it took some time to notice that only one speaker was playing.
Drive them with a conventional amplifier and they play like normal speakers.
 
You must have special taste or preference, because the LS50 Meta has hardly any bass at all in my room, even with a ton of power to drive them.
My EQ suggestion was purely to lower the bass that you described as being way too much... Which still surprises me :)
 
You must have special taste or preference, because the LS50 Meta has hardly any bass at all in my room, even with a ton of power to drive them.
My EQ suggestion was purely to lower the bass that you described as being way too much... Which still surprises me :)
What amp are you using?
Yes I much prefer tight bass, even if it doesn't dig very low.
 
What amp are you using?
Yes I much prefer tight bass, even if it doesn't dig very low.
Typically, tight bass, is just a matter of a flat FR. So if you EQ pretty flat and do not have a lot of ringing in the room - then the bass will mostly be considered "tight".
My amplifiers are not well known. They are quite powerful and refined, though.
Me and friends, can't hear much of a difference, when comparing it to very expensive amplifiers, like YBA, McIntosh Hypex, Dan Dagostino and so on. But found them controlling very difficult speakers, like few others could. This is quite evident, when you quickly observe much deeper strong bass, while having more SPL, before the speakers gives in. You can simply see the bass "flap" less, as the volume goes up, because the amplifier has such a strong grip on the driver.
https://groundsound.com/pa3cc.php
I tried the never Hypex NC502MP. But a direct comparison did not really give me any clear result. I thought that there was a difference, then I did not. So I ended up just keeping my Groundsound's, since the upgrade would cost quite a lot with 6 channels for two 3 way active towers. It was smaller, and you could maybe find a measurement that made it look better. But when you can't hear it... then why upgrade for 3000$ ?

But again... I still believe that when you use a pretty flat speaker like KEF - you just have to EQ for bass below around 200Hz, and then you're good.

You could correct it a bit, but you really need to know how to measure, to do so... or just go with the precise measurements from ASR or Erin - and apply the right EQ - and believe/trust the data:
https://www.spinorama.org/speakers/KEF LS50 Meta/ErinsAudioCorner/index_eac-v1.html
I like speakers that are more flat through the upper midrange and lower tweeter(cross-over region), which is why I would EQ the KEF flat here - and also the reason why I just made my own with a KEF coax driver - since I was going to EQ it anyway, use bigger woofer and a closed cabinet.
 
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