KEF LS50 Bookshelf Speaker Review

[theyellowspecial]

EQ design

How would you take the optimized score and calculate optimized score with sub? Thanks, Maiky.

 

[Isokawa]

Thanks for @Maiky76 & @thewas

Great EQ , got LS50 since 2012 it is indeed a great improvement via Roon DSP

one question: Some of us have a Subwoofer ( here REL T7i ) to push the low before DSP easy age.
How to integrate SW with this EQ ?
My SW xover is 80 Hz with limited gain, the settings make of course SW too boomy then i dont use first line

Type Freq Gain Q
PEQ 65.0, 3.00, 1.78,...

Hi,

@thewas_ asked me to have a look at his EQ and run my optimizer.
here are the results:
Score with No EQ: 4.6
For AB comparison the EQed version need to be boosted and the LF Boost may result in a reduced dynamic range.

The initial fitting by @thewas_ is pretty good.
Only minor changes after the optimization resulting a slightly higher score.
Mostly due to smoother PIR and ON which is not easy to do by hand.
the Final gain no EQ vs Optimized EQ is quite decent.

TheWas_ EQ:
Score: 6.16

Type      Freq      Gain     Q
PEQ       67.2,     3.00,   2.00,...
PEQ      170.0,    -2.00,   1.00,...
PEQ      540.0,     1.60,   5.00,...
PEQ      830.0,    -2.40,   2.50,...
PEQ     1240.0,    -1.20,   8.00,...
PEQ     1650.0,     2.50,   3.00,...
PEQ     2640.0,    -2.80,   2.00,...
PEQ     4620.0,    -3.40,   3.00,...

Score after Optimization: 6.36

Type      Freq      Gain     Q
PEQ       65.0,     3.00,   1.78,...
PEQ      166.5,    -2.10,   0.88,...
PEQ      550.0,     1.40,   3.72,...
PEQ      830.0,    -2.40,   1.83,...
PEQ     1224.0,    -1.34,   9.45,...
PEQ     1609.0,     2.11,   2.65,...
PEQ     2764.0,    -2.80,   1.35,...
PEQ     4747.0,    -3.40,   3.00,...

EQ design



No EQ vs Optimized

 

[aarons915]

Thanks for @Maiky76 & @thewas

Great EQ , got LS50 since 2012 it is indeed a great improvement via Roon DSP

one question: Some of us have a Subwoofer ( here REL T7i ) to push the low before DSP easy age.
How to integrate SW with this EQ ?
My SW xover is 80 Hz with limited gain, the settings make of course SW too boomy then i dont use first line

Type Freq Gain Q
PEQ 65.0, 3.00, 1.78,...

The common wisdom is to EQ the bass using in-room measurements under the transition frequency and above that use anechoic measurements to EQ the response.

 

[Maiky76]

How would you take the optimized score and calculate optimized score with sub? Thanks, Maiky.

Hi,

Check this out:
https://www.audiosciencereview.com/...7v-spinorama-and-eq-inside.17283/#post-560611

You can calculate the SW score with the data
PPR_LF = 12.69 - 2.49*NBD_ON - 2.99*NBD_PIR - 4.31*log10(14.1) + 2.32*SM_PIR
about 8.40

@Isokawa
If you have a subwoofer
1. you need to have correct integration between the mains and the sub, best is to perform some measurements and add a HPQ filter to high pass the KEF
2. do EQ on the room + sub+Mains using preferably the MMM method


For measurements and LF EQ there is no such thing as near/far field the room/speaker location in the ruling factor
https://www.ohl.to/audio/downloads/MMM-moving-mic-measurement.pdf
And a live demo:

You'll be able to work with REW and add the LF EQ Biquads into your DSP.

 

[alkaizer]

Hello

I went to the shop today to try the new KEF LS50 wireless II, i was pretty impressed by the clarify of the sound and how separation between instruments.

But comparing with the older version, the new one is a big disappointment in bass factor.

im not sure if its because of the speakers being new and needs some time to break in, or the source quality, or EQ setting.....

the only bass option in the setting is "extra bass", couldn't find anything else.

appreciate any help, thanks

 

[thewas]

Bass response on both should be similar depending on the settings, most difference in bass comes from room and placement, was that identical for both?

 

[alkaizer]

Bass response on both should be similar depending on the settings, most difference in bass comes from room and placement, was that identical for both?

I know the bass isn't the same, I can see bass driver movement has bigger range in version 1, and version two I see it barely moving in and out.

 

[tecnogadget]

Hello

I went to the shop today to try the new KEF LS50 wireless II, i was pretty impressed by the clarify of the sound and how separation between instruments.

But comparing with the older version, the new one is a big disappointment in bass factor.

im not sure if its because of the speakers being new and needs some time to break in, or the source quality, or EQ setting.....

the only bass option in the setting is "extra bass", couldn't find anything else.

appreciate any help, thanks

They have prettying much the same driver size/motor and same cabinet size/volume. There should not be any really perceivable difference on the bass department, in fact that is asking too much. Both I & II wireless LS50 are great speakers, but they get even better with a subwoofer if bass is that much important to you.

I know the bass isn't the same, I can see bass driver movement has bigger range in version 1, and version two I see it barely moving in and out.

The thing is...that’s not really a bass driver per se, its a midrange driver...that is being used to reproduce some portion of the bass range (asking too much for it)

 

[thewas]

I know the bass isn't the same, I can see bass driver movement has bigger range in version 1, and version two I see it barely moving in and out.

Just looked at the German magazine "Stereoplay" measurements of both and actually the 2nd goes even a bit deeper having -3 and -6 dB points at 48 and 43 Hz while for the older its 55 and 47 Hz.
Due to copyright reasons I cannot upload them here but you can purchase them legally here
https://www.testberichte.de/d/einzeltest/stereoplay-456329.html
https://www.testberichte.de/audio-hifi/2680/lautsprecher/testberichte/stereoplay/2021-04-09.html

 

[richard12511]

I know the bass isn't the same, I can see bass driver movement has bigger range in version 1, and version two I see it barely moving in and out.

They should be almost exactly the same. Are they both in the exact same position. Position matters more than the speaker itself down low.

If they're in the same position, then maybe the new one is damaged?

Do you have a mic that would allow you to take measurements?

 

[D700]

I've got the LS50s, FYI distance from wall and corner can make huge impact on amount of bass, if you haven't ruled that out already.

 

[alkaizer]

so i went to the shop again, with CDs, USD, and bluetooth worked too.

tried my tracks that i played with the previous version of speakers. still i cant feel the bass as much.

i admit the room setup is different, the new version is in small room (with sound observer sheets) , the older version was in very big room (sold out though)

small room should help you feel the bass right?? i really think its the break in period.

 

[LTig]

so i went to the shop again, with CDs, USD, and bluetooth worked too.

tried my tracks that i played with the previous version of speakers. still i cant feel the bass as much.

i admit the room setup is different, the new version is in small room (with sound observer sheets) , the older version was in very big room (sold out though)

small room should help you feel the bass right?? i really think its the break in period.

Break in is a myth.

 

[alkaizer]

This reddit thread suggest 100-200 hours break in, doesn't sound like a myth to me

https://www.reddit.com/r/audiophile/comments/ctj6nx

 

[Sancus]

This reddit thread suggest 100-200 hours break in, doesn't sound like a myth to me

Welcome to ASR.

It definitely is a myth. Also, a reddit post where somebody guesses at something they don't really understand is not evidence of anything.

 

[Mart68]

if only Hoffman had put 200 hours on his speakers he would have realised that his Iron Law was nonsense.

What a time to be alive!

 

[Mart68]

seriously though this must be the most over-hyped speaker in history. No wonder that some punters are disappointed.

 

[alkaizer]

still a myth??

This is written in KEF official blog (cached)

https://webcache.googleusercontent....+&cd=1&hl=en&ct=clnk&gl=kw&client=firefox-b-d

 

[Sancus]

still a myth??

This is written in KEF official blog (cached)

https://webcache.googleusercontent....+&cd=1&hl=en&ct=clnk&gl=kw&client=firefox-b-d

Yes, still a myth. Repeating boring things already discussed in the dedicated thread for that boring topic changes nothing.

 

[BoredErica]

It can and it does. I don't currently have confidence in what it is showing however. As I test larger speakers, I can better tell how good that metric is. Here is what it looks like for KEF LS50 for example:
View attachment 47994

The highest order function flattens at about 0.6 meter where I have drawn that arrow. That means from there on we are in far field. Someone less lazy than me can do the math and tell us if this is correct

@amirm Sorry to bump this old thread. Hopefully it's less boring than talking about burn-in.
Has there been any updates on this front, now you've tested larger speakers? My understanding is there is a certain distance one should sit from a speaker so different drivers 'integrate'. For example, the tweeter and the woofer in most speakers are in different locations, and if my ear is tweeter level and super close, the sound won't be right,. But I also thought for a speaker like the LS50 (or its Meta version), the drivers would integrate even when sitting a few inches away?

Thanks