• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

KEF LS50 Meta Review (Speaker)

In my experience the LS50 Meta + AudioLab 6000A can go very loud, much louder than I would ever need, or endure. At normal volumes the combination sounds excellent. I cannot comment on any other combination.
It is a nice amp from the description and basic specs. The 60,000 micro Farads of supply capacitance and the 9 amps of power into low impedances really boosts the peak output into the load so it probably does sound more substantial than most average 50W/ch amps. I had a 75W/ch amp that was very high current (1kW mains transformer and a beefy design) and had a 300W/ch output into 2 Ohms and it was veryyy loud for a 75W/ch amp. So I can understand that this might be enough power for you with your present speakers.
z Screenshot 2023-04-06 154912.png
 
It is a nice amp from the description and basic specs. The 60,000 micro Farads of supply capacitance and the 9 amps of power into low impedances really boosts the peak output into the load so it probably does sound more substantial than most average 50W/ch amps. I had a 75W/ch amp that was very high current (1kW mains transformer and a beefy design) and had a 300W/ch output into 2 Ohms and it was veryyy loud for a 75W/ch amp. So I can understand that this might be enough power for you with your present speakers.
View attachment 277564
Agreed, those are nice specs. I'm gonna have to take another look at Audiolab.
 
It is a nice amp from the description and basic specs. The 60,000 micro Farads of supply capacitance and the 9 amps of power into low impedances really boosts the peak output into the load so it probably does sound more substantial than most average 50W/ch amps. I had a 75W/ch amp that was very high current (1kW mains transformer and a beefy design) and had a 300W/ch output into 2 Ohms and it was veryyy loud for a 75W/ch amp. So I can understand that this might be enough power for you with your present speakers.
View attachment 277564
Measurements on hifi new dot com give a dynamic power rating of 133 W into 4 Ohm with < 1% THD, and a constant power rating of 85W into 4 Ohm with < 1% THD.
 
Measurements on hifi new dot com give a dynamic power rating of 133 W into 4 Ohm with < 1% THD, and a constant power rating of 85W into 4 Ohm with < 1% THD.
Respectable test results. :D
 
Lmao, I sold those ls50 metas to him a few days ago. Glad he's enjoying them ;) I miss them dearly.
Out of curiosity, why did you sell them?
 
what crossover have yall been using?

i was using 80hz but tried 120hz and i think i like it more for my 2.1 nearfield set up at my gaming/media desk in bedroom with kef ls50 meta and svs sealed 1000 pro sub with the Denon AVR-X1400H AVR

and can anyone explain what thi localiztion thing people speak about in relation to subs and crossovers?

if i extend my leg i can touch the sub with my foot, thats how close to it i am, so i dont know if i need to worry about that.
 
People are generally unable to find the exact spot where wavelength lower than 80 Hz originate ..... in other words, they can't "localize" them. As frequencies rise above 80 Hz, our hearing system rapidly gains the ability to localize a sound. (Some people say this is an outgrowth of our survival mechanism.)

If the bass system we use contributes sound that has significant content above 80 Hz, due either to high amplitude or high frequency content from a low-slope crossover, we'll be able to point right at the driver and say, "There it is!". (That's localization.)
That's not really a problem ..... unless the signal from the right channel or left channel is pulled towards the bass driver because the level of the bass signal is too high. It'll sound as if the right channel (for instance) signal is coming from both the right hand speaker AND the bass driver location. Weird and confusing with acoustic content, but perhaps somewhat less so with electronic music.

We can get used to it, but it will always sound unnatural.
Two subs allows us to position the subs right under the left and right speaker, so that even if the signal from the sub is too high in frequency or amplitude, the directional cue is in-line with the left or right higher-frequency signal.

Jim

thanks! since i am so close my foot can touch the sub, would i have to worry about that at 120hz crossover? i think that sounds the best so far, i tried going over to even 150hz or 200z but regardless of the localization thing, they did not sound as good i think
 
They don't have grills, and my toddler is very unpredictable.

That was a very puzzling decision by KEF. Speakers really don’t need their junk hanging out like that.

Even if I hadn’t liked Technics C700 a lot more than OG LS50, C700’s grille made the choice a lot easier.
 
I have never found a sub satellite system that sounded good crossed over at 120Hz+. After a few days of listening they all sounded too boomy and too thumpy.
I added a sub for music, properly crossed at 65Hz for some ELAC bookshelves. Girlfriend said she couldn’t hear it til I cranked it to 120Hz using the SVS app. Tried to tell her the point was not being able to localize the subwoofer. She just thinks I wasted $750. :) Nice girl. Terrible hearing.
 
I added a sub for music, properly crossed at 65Hz for some ELAC bookshelves. Girlfriend said she couldn’t hear it til I cranked it to 120Hz using the SVS app. Tried to tell her the point was not being able to localize the subwoofer. She just thinks I wasted $750. :) Nice girl. Terrible hearing.
Well... At least you got a sub and where not banned from purchasing...LoL. :D
 
Higher crossovers (120 - 150Hz) can work well if you use steeper low-pass filters (24 - 48 dB/octave) on your subs. This is assuming you have the equipment to measure and EQ. If not, then 80 Hz is the safer choice to avoid localization for a single sub. As others have mentioned, localization becomes less of an issue when you have 2 or more subs in the room.
 
Subs on the floor dont function well above 100 Hz , and should have at least 24/dB oct lowpass filtering if only one is used . However, crossing a single subwoofer that high ( if its on the floor ) will bring a bad sound result.

If two subwoofers are connected very close to or below each main speaker and in stereo, or the two stereo coupled subwooferdrivers is at the same hight as each of the the main midbass driver, one can get away with a 6 dB lowpass crossover - this will then be a bass reinforcement speaker and can bring very good sound results.

If I had a pair of ls50 meta I would build two tower shaped subwoofers with the same hight as the metas, placed very near each ls50, in stereo.
The ls50 should be plugged to behave as a closed box. Because of that, I would use an inverted 12 dB/oct stereo lowpass crossover for the stereo subs. Probably around 70 Hz , near where the meta:s roll off as a closed box .

This way, no high pass crossover is needed for the metas.

An even better result can be had with a real separate stereo crossover with both HP and LP filtering .

One option is to use a passive line level crossover to roll off the closed ls50 with 6 dB /oct , then the subwoofers should be crossed with a noneinverted 18 dB/oct crossover .
Combined, it will be a 18/18 LP HP acoustical crossover .
 
Last edited:
  • Like
Reactions: pjn
Does the pair of JBL 305P MK II connected to a good DAC will sound more Hi-FI than KEF LS50 Meta for music listening in the room?
 
Does the pair of JBL 305P MK II connected to a good DAC will sound more Hi-FI than KEF LS50 Meta for music listening in the room?
The ls50 meta is probably a better sounding speaker ( I have had jbl 305p mkII ) even with a cheap amp . Even If spinorama and frequency response would be almost similar , the bad resonant cabinet in the 305 will show up with a less good sound. That said, Jbl 305p MKII is probably one of the best sounding speaker on the market below 250 dollars/pair.
 
Last edited:
I have never found a sub satellite system that sounded good crossed over at 120Hz+. After a few days of listening they all sounded too boomy and too thumpy.

I felt the same way when I was restricted to crossing over both at the same frequency and the reason is because the high pass is a 2nd order while the low pass is 4th order on the sub so you'll get too much energy around the crossover region. At 120Hz, a 2nd order high pass is down 6 db at 90Hz so that is actually where your low pass should be but receivers don't allow this. I use Equalizer APO with the Peace addon and it does let you do independent settings for each and I am able to do these different combinations that sum better and don't sound boomy, although for my listening levels 100Hz(with an 85Hz lowpass) is as high as I need to go.
 
Back
Top Bottom