KEF LS50 disappointment :(

[hg]

Because they are sized to be used at a 1m listening distance.

That would be one useless pair of speakers.

You would consider the market for desk speakers/nearfield monitors to be insignificant?

 

[Frank Harvey]

You would consider the market for desk speakers/nearfield monitors to be insignificant?

No, just different.

I agree that they're perfect for near field listening/monitoring - their UniQ array is far better than the majority of loudspeakers out there for this purpose, but they've not been primarily designed to be sat on computer desks and hooked up with little amplifiers. KEF's X300A is far better suited to that purpose, and is less fussy on positioning and partnering equipment. There's a wealth of 'powered speakers' out there that are far more suitable to sitting either side of a PC screen than the LS50, which really comes into its own when positioned properly on decent stands and partnered with capable electronics.

 

[Frank Harvey]

The reference level requires an average level of 85dB with peaks of 105dB. This is the level in a cinema, around the level for long term monitoring in a studio and around the level an enthusiast would listen to music in the home. The average level is rarely a problem but handling the peaks cleanly can be a problem if the speakers are inadequately sized.

It's all relative to listening distance though, so speakers in a cinema will be working far harder to achieve 85dB than your own speakers achieving 85dB in your living room.

The LS50s cannot take 200W. The SPL falls by 6dB with a doubling of distance (some caveats) and so at 2m the LS50 would need to accept 400W but the real problem would be the very large linear deflection of the cones.

You'd be surprised what speakers can take when it is presented to them cleanly. This not only depends on listening distance, but also on how long the speaker is required to reproduce 200w - much of the time it will be split seconds, maybe a second or so for movies. It will also depend on frequency.

No one is going to buy a speaker the size of an LS50 to continuously reproduce excessively high SPLs, so I'm not really sure why you're trying to denigrate the design. As I have mentioned before, if you're using output/distance measurements used for cinemas, then from what you're saying, you're making assumptions that they're being used full range and without a subwoofer. In an AV system, they will be used with a sub, and their crossover point set at anywhere between 70-200Hz depending on listening distance and sub capability - the mid/bass cones are then doing a lot less work, 'deflecting' far less, and able to play louder. If you haven't heard an AV system comprising LS50s, I would highly recommend doing so.

 

[hg]

I agree that they're perfect for near field listening/monitoring - their UniQ array is far better than the majority of loudspeakers out there for this purpose, but they've not been primarily designed to be sat on computer desks and hooked up with little amplifiers. KEF's X300A is far better suited to that purpose, and is less fussy on positioning and partnering equipment.

The size and SPL output of the X300A and the LS50 are essentially the same. They are both suitable for use as high quality desk speakers but neither is suitable as high quality main speakers because they are well short of being able to reproduce musical peaks at the reference level. If a person only wants to listen quiety and/or only wants to listen to music with a strongly suppressed dynamic range perhaps they might be suitable as main speakers but they would appear to be unsuitable otherwise.

 

[BigH]

So what is the minimum size for main speakers? If 5 inches are too small.

 

[Vladimir]

No one will buy a pair of KEF LS50s for what they really are but for what they are presented to be. These are speakers aimed at audiophiles who don't understand the engineering side of how hi-fi works and relly on a company heritage, reputation, other people opinions etc. to decide if what is presented is true. When the design is subjected to scrutiny, skepticism and analysis, apologetics who pushed the initial hype begin deflating and inflating. Like shooting at a moving target.

- These LS50s are bloody amazing, giant killers, amazing sound for so little money [inflate].

- But they don't even do 105dB with reasonable amount of distortion. Actually the specs are lacking and feel manipulated. 85dB average and extra 20dB in peaks is not that much or anything to write home about.

- Yes, they don't perform as you say at 105dB [deflate], however if you buy a special amplifier, with special cables and a very good active sub to take away all the hard work off of them, they will be amazing as promised [inflate].

Wait a minute. Weren't these suposed to be amazing without a sub, in a typical middle sized room, with any decent amp fed to them? Guess what a KEF LS50 owner will do next?

a) Sell his just recently purchased and cherished speakers and buy better ones.

b) Buy special (read: more expensive) cable, stands, active subwoofer and a special amplifier? (skhumar is in this current dilemma)

@David

No one is degrading the actual design, we are trying to understand it objectively for what it really is, with all of its strengths and limitations like any other speaker. This gives balance to the hyped industry praise (everyone on the take: manufacturer, reviewers, dealers). Hopefully at the end of this discussion we all end up with reasonable expectation what the KEF LS50 can really do.

My contra-leverage to the hype so far:

1) They cannot play loud at satisfactory SPL for some people, including myself.

2) They are not a full range sound loudspeaker, and I like my grand piano and double bass.

3) They have significant amounts of distortion bellow 100Hz, although nothing to give you a headache due to nature of the harmonics.

therefore,

4) They do not perform as good as studio monitors and are not intended as such.

5) They do not perform as good as large hi-fi floorstanders and are not intended to do so.

and an added extra,

6) They are nothing similar to the BBC LS3/5a in its design and no more 'BBC' in their design goals more than any other mini monitor hi-fi loudspeaker.

Every criticism aimed at the KEF LS50 in this thread is equaly valid for all small form factor domestic hi-fi speakers. If Tannoy hyped their DC6 mini monitor dual concentrics to have super powers, most likely this thread would have been about them.

Interesting debate among the staff at Stereophile on the topic of bookshelf vs floorstanders.

That said, however, I would like to express my growing personal distaste for small monitor speakers and for the dishonesty with which they are advertised and reviewed. I can see a limited need for such units in the field and in very unusual listening conditions. I do not, however, see a need for such speakers in most listening rooms. I see no valid design reason for producing them, and feel they deserve far more criticism than they now get...

Who Stole The Bass? / No One Stole The Bass

 

[Frank Harvey]

The size and SPL output of the X300A and the LS50 are essentially the same. They are both suitable for use as high quality desk speakers but neither is suitable as high quality main speakers because they are well short of being able to reproduce musical peaks at the reference level. If a person only wants to listen quiety and/or only wants to listen to music with a strongly suppressed dynamic range perhaps they might be suitable as main speakers but they would appear to be unsuitable otherwise.

Firstly, while cone area might be very similar, the quality of drivers are completely different, so the LS50 will be capable of more output, and better quality output at that. The X300s essentially use a Q100 UniQ.

Secondly, "Reference Level" is something attached to movie viewing and cinemas - it doesn't exist in home hi-fi.

"Strongly suppressed dynamic range"? Really? I found them better than some larger speakers...

 

[drummerman]

Take the tweeter and its surround away and the cone area really is very small, probably close to 90/100 milimeter.

It is just asking for the impossible for a speaker and cone area that small to provide high SPL, dynamic range or full bandwidth.

That of course doesn't mean it is a bad speaker within it's capability.

Never heard them.

 

[BigH]

No one will buy a pair of KEF LS50s for what they really are but for what they are presented to be. These are speakers aimed at audiophiles who don't understand the engineering side of how hi-fi works and relly on a company heritage, reputation, other people opinions etc. to decide if what is presented is true. When the design is subjected to scrutiny, skepticism and analysis, apologetics who pushed the initial hype begin deflating and inflating. Like shooting at a moving target.

- These LS50s are bloody amazing, giant killers, amazing sound for so little money [inflate].

- But they don't even do 105dB with reasonable amount of distortion. Actually the specs are lacking and feel manipulated. 85dB average and extra 20dB in peaks is not that much or anything to write home about.

- Yes, they don't perform as you say at 105dB [deflate], however if you buy a special amplifier, with special cables and a very good active sub to take away all the hard work off of them, they will be amazing as promised [inflate].

Wait a minute. Weren't these suposed to be amazing without a sub, in a typical middle sized room, with any decent amp fed to them? Guess what a KEF LS50 owner will do next?

a) Sell his just recently purchased and cherished speakers and buy better ones.

b) Buy special (read: more expensive) cable, stands, active subwoofer and a special amplifier? (skhumar is in this current dilemma)

@David

No one is degrading the actual design, we are trying to understand it objectively for what it really is, with all of its strengths and limitations like any other speaker. This gives balance to the hyped industry praise (everyone on the take: manufacturer, reviewers, dealers). Hopefully at the end of this discussion we all end up with reasonable expectation what the KEF LS50 can really do.

My contra-leverage to the hype so far:

1) They cannot play loud at satisfactory SPL for some people, including myself.

2) They are not a full range sound loudspeaker, and I like my grand piano and double bass.

3) They have significant amounts of distortion bellow 100Hz, although nothing to give you a headache due to nature of the harmonics.

therefore,

4) They do not perform as good as studio monitors and are not intended as such.

5) They do not perform as good as large hi-fi floorstanders and are not intended to do so.

and an added extra,

6) They are nothing similar to the BBC LS3/5a in its design and no more 'BBC' in their design goals more than any other mini monitor hi-fi loudspeaker.

Every criticism aimed at the KEF LS50 in this thread is equaly valid for all small form factor domestic hi-fi speakers. If Tannoy hyped their DC6 mini monitor dual concentrics to have super powers, most likely this thread would have been about them.

Interesting debate among the staff at Stereophile on the topic of bookshelf vs floorstanders.

That said, however, I would like to express my growing personal distaste for small monitor speakers and for the dishonesty with which they are advertised and reviewed. I can see a limited need for such units in the field and in very unusual listening conditions. I do not, however, see a need for such speakers in most listening rooms. I see no valid design reason for producing them, and feel they deserve far more criticism than they now get...

Who Stole The Bass? / No One Stole The Bass

i do agree about hyping up certain products by hifi mag reviews don't think its a good idea and I must say WHF are probably the worst with their annual awards. As for the ls50s they are compromised like all speakers but not so much as the CM1s in my opinion. As for stereophile article, some good points but more for their market than the uk. Also live music is not always better, why do they think live music is always perfect, many concerts I've been to have problems with the sound.

 

[matthewpiano]

All this stuff about reference levels is divorced from domestic realities for most people. Many of us have something called neighbours who don't wish to hear our music.

My Dynaudio DM2/6 and KEF Q100 are both small speakers but both produce excellent results.

 

[Vladimir]

The B&W CM1s are heavily compromised and are IMO only good as background music speaker, which is what I use them for.
No illusions about them being accurate or as good as floorstanders.

 

[Frank Harvey]

No one will buy a pair of KEF LS50s for what they really are but for what they are presented to be. These are speakers aimed at audiophiles who don't understand the engineering side of how hi-fi works and relly on a company heritage, reputation, other people opinions etc. to decide if what is presented is true.

I find this statement be total BS. I bought them because of what they do, over and above similarly priced designs, and even some more expensive ones. I'd do it again too.

Snip the fabricated nonsense...

Wait a minute. Weren't these suposed to be amazing without a sub, in a typical middle sized room, with any decent amp fed to them? Guess what a KEF LS50 owner will do next?

a) Sell his just recently purchased and cherished speakers and buy better ones.

b) Buy special (read: more expensive) cable, stands, active subwoofer and a special amplifier? (skhumar is in this current dilemma)

Not really sure where you're getting this fairytale stuff from...

@David

No one is degrading the actual design, we are trying to understand it objectively for what it really is, with all of its strengths and limitations like any other speaker. This gives balance to the hyped industry praise (everyone on the take: manufacturer, reviewers, dealers). Hopefully at the end of this discussion we all end up with reasonable expectation what the KEF LS50 can really do.

I'm sure if there were any serious limitations, independent reviews would've picked up on them and make them known. Everyone knows the bass isn't the deepest you can get, what do you expect from such a small bass driver? And also from such a small cabinet volume?! I think some people need to take a step back and ground themselves back in reality. I could understand if everyone was having a go at a large floorstanding speaker that didn't perform like a large floorstanding speaker, but this is a small bookshelf speaker! The bass they do have is very well balanced.

1) They cannot play loud at satisfactory SPL for some people, including myself.

You don't like them? They don't do what you require? That's fine! But there is no need to try and put everyone else off the because you made the mistake of buying them (if indeed you did own a pair, and actually spent any reasonable time with them). There are a lot of happy owners out there who enjoy listening to them. Obviously, they don't join up on forums to say how good they are and how much they are enjoying them.

2) They are not a full range sound loudspeaker, and I like my grand piano and double bass.

Technically speaking, they are a full range loudspeaker - they are not a satellite speaker as you would be describing. Again, size has limitations - if you want low bass from a tiny cabinet, you sacrifice in other areas, and you pay more money. Or you buy big Floorstanders or some subs. Easy.

3) They have significant amounts of distortion bellow 100Hz, although nothing to give you a headache due to nature of the harmonics.

I don't know, I haven't measured them, only listened to them (music and movies). Everything I heard sounded clean, and that includes the bass. Jack is the best one to comment on this aspect, as the product (like any other product) will include trade offs for gains in other more important areas.

4 and 5 are self explanatory. 6 isn't for me to comment on.

That said, however, I would like to express my growing personal distaste for small monitor speakers and for the dishonesty with which they are advertised and reviewed. I can see a limited need for such units in the field and in very unusual listening conditions. I do not, however, see a need for such speakers in most listening rooms. I see no valid design reason for producing them, and feel they deserve far more criticism than they now get...

So you don't like standmounts? Are you as vocal on other worldwide forums about cars you dislike? Groups or artists you don't like? Films you don't like? Wallpaper?

Why don't you put all the energy you're using towards something positive, and talk about products you do like? That would make any place more enjoyable for existing members and also for new members. Spending time trying to make people aware of negatives is wasted time - these companies will continue to exist no matter how much of a life goal you make it to achieve otherwise. If you don't like them, say your piece and be done with it, rather than rambling on about how a tiny speaker can't produce AC/DC at realistic gig levels.

There is a growing need for smaller speakers in the UK, as end users generally don't want wardrobes in their living rooms (well, their other half, to be more precise). So to may not see a "valid design reason", but others will, hence why manufacturers go to the trouble to design, build, and market such a speaker.

Honestly, the hate for certain products and manufacturers around hi-fi forums recently is verging on disgusting, and in my view, is only having an affect on the industry as a whole, rather than the manufacturers and products that are being targeted. Then again, maybe that's the end game for these individuals.

 

[BigH]

The B&W CM1s are heavily compromised and are IMO only good as background music speaker, which is what I use them for. No illusions about them being accurate or as good as floorstanders.

so floor standers are the answer now. Which ones do you use?

 

[Vladimir]

Since clicking links is a bother, I'll quote some of the content.

That said, however, I would like to express my growing personal distaste for small monitor speakers and for the dishonesty with which they are advertised and reviewed. I can see a limited need for such units in the field and in very unusual listening conditions. I do not, however, see a need for such speakers in most listening rooms. I see no valid design reason for producing them, and feel they deserve far more criticism than they now get.

Let me begin by summarizing my reasoning in nontechnical terms:

• Whether a speaker is large or small, unless designed to be used adjacent to a wall, it still has to be the same distance from the rear and side walls for best performance. In addition, small speakers require fairly high stands. The illusion that small monitor speakers are easier to place than conventional speakers ignores the real-world laws of speaker placement.

• The laws of physics simply do not permit a speaker with a usable sensitivity to generate accurate bass below 120Hz from a small cabinet. Whether or not the speaker is equalized, something has to give, usually at the expense of accuracy from the lower midrange down. The issue is not deep bass or performance in a limited range of music, but mediocre performance in the area where most music has most of its energy.

• These speakers do not produce a better midrange at the expense of bass---they simply produce more midrange energy relative to the bass. A small enclosure demands far more compromises on getting flat and dynamic lower midrange than a larger one, and virtually forces the designer to play some sort of design trick to get the illusion of acceptable bass. At a given price, a talented designer is going to do better with a larger enclosure (footnote 1).

• If a small speaker with a restricted bass range or low-frequency dynamics has flat upper octaves, it will never sound musically natural. No live performance ever has such a balance in timbre; the imaging will be artificially exaggerated, and the soundstage will tend to be too wide and diffuse. There will be too much transient detail because the upper octaves will not be masked or balanced by adequate lower-midrange and upper-bass information.

• If a small speaker with restricted bass range or dynamics has rolled upper octaves, so that the highs seem natural in proportion to the lows, we get "polite" music with a sweet, comfortable sound, but no real bite and power. The result is fine for background music, but it is about as satisfying as a polite painting, a polite wine, or any other polite pleasure.

• In both cases, the listener eventually tends to restrict their listening to the music that suits the speaker rather than explore the full range of musical experience. The speaker is not supposed to help you select your music.

• There is no reason for the existence of such speakers. Virtually all of the better mini-monitors are British. Though generally reasonably priced in the UK, they are grossly overpriced in the US relative to full-range US speakers, such as models from Thiel, Vandersteen, VMPS, etc.

• While subwoofers or external woofers can help, only a bass unit specifically designed to work with a small monitor can really perform well. Most small monitors have to alter their low bass to provide some kind of boost so they sound reasonably good when used alone. This makes blending with a bass unit far more difficult.

• A single, separate bass unit will degrade imaging and the presentation of depth with a stereo system unless it crosses over well below 80Hz. Even a single bass unit, however, tends to raise the cost of a small monitor system above that of a full-range speaker system. Further, most combinations of small monitors and bass units are far uglier than a pair of full-range speakers, and harder to place in a listening room. They also involve very complex hookups, and often mean extra amplifiers and interconnects---all of which cost money and degrade sound quality.

These generalizations have a sound technical base, but many of these problems are not fully apparent to the audiophile because there are no universally accepted standards in the audio industry for measuring low-frequency response and dynamic range in loudspeakers.

 

[Vladimir]

The B&W CM1s are heavily compromised and are IMO only good as background music speaker, which is what I use them for. No illusions about them being accurate or as good as floorstanders.

so floor standers are the answer now. Which ones do you use?

They were always the answer. I currently use the old and moldy Sony SS-F7ESG.

 

[dim_span]

some interesting info on the Jordan Eikona speakers.... they don't use tweeters etc

http://www.ejjordan.co.uk/faq/

 

[Vladimir]

some interesting info on the Jordan Eikona speakers.... they don't use tweeters etc

http://www.ejjordan.co.uk/faq/

They seem excellent for Norah Jones and Diana Krall music. *wink*

 

[hg]

Firstly, while cone area might be very similar, the quality of drivers are completely different, so the LS50 will be capable of more output, and better quality output at that. The X300s essentially use a Q100 UniQ.

KEF quote maximum SPLs of 104dB and 106dB without specifying the conditions. This does not look like a significant difference.

Secondly, "Reference Level" is something attached to movie viewing and cinemas - it doesn't exist in home hi-fi.

This is not correct. Our hearing is non-linear and the level we listen at significantly changes the tonal balance we perceive. This is why the film industry specifies the playback level so people hear what was intended. The same is true for music and if people wants to hear what was intended one of the criteria that must be met is an undistorted playback level somewhere around the reference level.

 

[dim_span]

some interesting info on the Jordan Eikona speakers.... they don't use tweeters etc

http://www.ejjordan.co.uk/faq/

They seem excellent for Norah Jones and Diana Krall music. *wink*

I have not heard these, but they come highly recomended by Tom Evans.

 

[Vladimir]

Firstly, while cone area might be very similar, the quality of drivers are completely different, so the LS50 will be capable of more output, and better quality output at that. The X300s essentially use a Q100 UniQ.

KEF quote maximum SPLs of 104dB and 106dB without specifying the conditions. This does not look like a significant difference.

Jack said the LS50 dual concentric driver is a modified Q100. That would explain the shared performance margins.

 

[Electro]

some interesting info on the Jordan Eikona speakers.... they don't use tweeters etc

http://www.ejjordan.co.uk/faq/

They seem excellent for Norah Jones and Diana Krall music. *wink*

I have not heard these, but they come highly recomended by Tom Evans.

These might be of interest they use full range jordan drivers plus an extra fully adjustable output tweeter in a transmission line cabinet .

http://websites.uk-plc.net/Ultra_Resolution_Loudspeakers/phantom-source-floorstander-38825.htm

 

[hg]

So what is the minimum size for main speakers? If 5 inches are too small.

The minimum size is something like that required to produce 85dB average with 20dB headroom for the peaks at the listening position. So we want the short term peak performance of the amplifier and speaker to be capable of about 105dB plus 6dB for every doubling of distance of 1m away. So 2m away would require 111dB at 1m and 4m away would require 117dB at 1m.

Perhaps the easiest way to get a feel for the SPL capabilities of various sizes of speakers is to browse the measurements on the Neumann site for their studio monitors. If you click on the details for a monitor and then on the measurements section on the RHS you will see a plot of SPL at 1m against frequency for 1%, 3% and 10% total harmonic distortion.

The KH 120 is about the size of the LS50 although without the issue of modulating the tweeter output.

The KH 420 plus subwoofers is starting look a comfortable size. The classic configuration used to be 12" woofer, 5" midrange and 1" tweeter but these days for home use it has become more like 2 x 8" woofers, 5" midrange and 1" tweeter in a tower.

PS The spam filter is not letting me link to the Neumann site.

 

[Vladimir]

Neumann studio monitors.

Trivia: They also made the Oy monitors that Manfred Eicher from ECM records uses in his office to demo CDs still to this day.

 

[BigH]

So what is the minimum size for main speakers? If 5 inches are too small.

The minimum size is something like that required to produce 85dB average with 20dB headroom for the peaks at the listening position. So we want the short term peak performance of the amplifier and speaker to be capable of about 105dB plus 6dB for every doubling of distance of 1m away. So 2m away would require 111dB at 1m and 4m away would require 117dB at 1m.

Perhaps the easiest way to get a feel for the SPL capabilities of various sizes of speakers is to browse the measurements on the Neumann site for their studio monitors. If you click on the details for a monitor and then on the measurements section on the RHS you will see a plot of SPL at 1m against frequency for 1%, 3% and 10% total harmonic distortion.

The KH 120 is about the size of the LS50 although without the issue of modulating the tweeter output.

The KH 420 plus subwoofers is starting look a comfortable size. The classic configuration used to be 12" woofer, 5" midrange and 1" tweeter but these days for home use it has become more like 2 x 8" woofers, 5" midrange and 1" tweeter in a tower.

PS The spam filter is not letting me link to the Neumann site.

But Neumann seem to be active speakers?

 

[hg]

But Neumann seem to be active speakers?

I am intrigued. Why do you think that might be relevant when it comes to getting a feel for the SPL that various driver configurations can produce?

Neumann speakers obviously perform well or else they would not publish reasonably full specifications but other good quality speakers will be in the same performance ball park.