Active Kef LS50

[wgb113]

Been away for a while - enjoying music and not worrying about gear!  Ran into an issue with my nearly 3yr old LS50Ws this past Monday.  Posted about it a couple of other places but figured I'd add it here as well:

 

First the stats:

• Manufactured 11/2016
• Running latest firmware.
• Approx. 150 - 200 hours on them.

Was listening to albums for about 3 hours on Sunday and everything was perfectly fine. Went to listen to an album Monday night and about half a side in it sounded like the left (slave) speaker’s woofer stopped working.

Played through the rest of the side (was needledropping) and then switched to the Optical input to rule out the Turntable and Phono Preamp as the fault. Used a mono CD and confirmed it was an issue with the speaker.

 

Checked the firmware version, it was up to date.

 

Disconnected and reconnected all source connection and the speaker-to-speaker cable.

 

Performed a Reset which did not work.

 

Unplugged both speaker’s power cords for a minute and reconnected. Everything was working fine again…for about a minute.

 

Unplugged just the slave speaker’s power cord - did not work.

 

Unplugged just the master speaker’s power cord - sound came back as normal…for about a minute.

 

Contacted KEF USA and they requested I send the speakers back which I’m doing today.  I’m obviously well out of the curiously short 1 year warranty at this point which is my reason for updating this post - to see how they deal with out-of-warranty repairs. I agree with the earlier poster that suggested KEF should have simply extended the warranty on all LS50Ws within a given production batch to at least 5 years (the standard warranty on the much-less complex passive speakers). They could have saved a lot of the bad feeling that have resulted as well as the hesitation prospective buyers feel when they come across the issues that are being reported.

 

As a big KEF fan I’m hoping they’re able to fix my pair at no extra charge other than shipping. I love the LS50W as it seems to me to be the fully-realized version of what they intended the LS50 to be (I lived with the passives for close to 4 years). I really don’t want to have to start a new search at this point, even though there are more options now than there were 3 years ago.

I’ll report back in about a month (they quote a 3 week turnaround time to diagnose and repair).

[Fridolin]

I have the very same problem with my LS50Ws.

On the left speaker bass drops out about every minute for a while and then comes back.

Very annoying!

 

I have to send them to my dealer and hope it won't be too expensive to repair them.

[wgb113]

So I got an update yesterday. Both “main boards” had to be replaced. They should ship Monday and I’ll have them back Tuesday/Wednesday.

As far as I know they replaced them free (except for shipping to them) and they’re 2 years out of warranty which I think is the right thing for them to do so, we’ll done KEF.

There does seem to be an unforeseen issue with early batches that hopefully has been fixed as they began to see problems. Still wish they would have done something similar to what Subaru did with the CVT on our Forester and simply sent a letter to owners stating they’d extended the warranty on them rather than leaving uncertainty out there.

Can’t wait to get them back!

[ariel]

well after 2.5 years of enjoying music ln the LS50W on an almost daily basis, today they started to act up, after an initial loud pop, the power icon started to blink (all other icons are off). After removing power and waiting for a few minutes, the speaker system boots up normally and works for a few minutes to an hour, and then it dies again.

I was running 1-year-old firmware - I just updated the pair to v4.1 (posted a few days ago). The update completed successfully but after a while the same issue started to happen.

 

Anyone had this problem? I'm wondering if it's worth trying a factory reset

 

[wgb113]

I'd reach out to KEF - they took care of my pair well out of warranty and I was only out shipping costs to them.

[ariel]

I did connect with KEF and had a very fast response (their support seems great) - however, noticing the that issue seemed to 'build up' over time and then suddenly 'spark', and that the air here (winter time) got really dry specially since last week, I used an electronics (no-moisture) air duster, very gently and from the exterior (through connectors etc). The thought was that maybe some particle + much higher than usual static was causing this. I did that two days ago and since then I've been using the speakers for many hours on end, with no re occurrence.

If they do fail again anytime I'm planning to drop them off at the local KEF service center. Although I'm hoping that I will get a few more years of great listening before that happens. Let's see.

FWIW firmware 4.1 seems solid - ugraded using a mac with no issues. Unfortunately older speakers do not get the new "remote power on" feature. It would have been a great addition.

 

[Emm]

I purchased, a week ago, a pair of LS50w mainly for my wife and kids (to keep them away from my main system).

The value for the price is impressive and the sound was dramatically improved (I mean really dramatically) after some upgrades. 

Namely:

- Ifi Power Station (this device is a killer for the money)

- Wireworld Silver Electra power cables

- Wireworld Platinum Starlight Ethernet cable to connect the two speakers 

- Audioquest Diamond USB with Carbon DBS (...and Duracell batteries- a friend has insisted on this combination who claims that he can hear differences between different batteries brands....I don’t have a personal opinion but I am very pleased with the cable).

- the factory rubber feet were removed and adjustable spike cones are installed.

 

the sound is now very impressive and hard to believe 

[erniejade]

I use Cullen  power  cables and star sound spike cones.  You are right, the speakers do respond  well to small tweaks. 

 

Btw, in my other rig, i have audioquest cv8 72V  speaker cables and i agree  on the battery  choice  as well. I don't  know how to explain  how the battery  can make a difference  but it did.  

 

  Do you have a sub on them?  

[Emm]

16 minutes ago, erniejade said:

I use Cullen  power  cables and star sound spike cones.  You are right, the speakers do respond  well to small tweaks. 

 

Btw, in my other rig, i have audioquest cv8 72V  speaker cables and i agree  on the battery  choice  as well. I don't  know how to explain  how the battery  can make a difference  but it did.  

 

  Do you have a sub on them?  
 

I do, KEF KF92

 

[PAR]

8 hours ago, Emm said:

I purchased, a week ago, a pair of LS50w mainly for my wife and kids (to keep them away from my main system).

The value for the price is impressive and the sound was dramatically improved (I mean really dramatically) after some upgrades. 

Namely:

- Ifi Power Station (this device is a killer for the money)

- Wireworld Silver Electra power cables

- Wireworld Platinum Starlight Ethernet cable to connect the two speakers 

- Audioquest Diamond USB with Carbon DBS (...and Duracell batteries- a friend has insisted on this combination who claims that he can hear differences between different batteries brands....I don’t have a personal opinion but I am very pleased with the cable).

- the factory rubber feet were removed and adjustable spike cones are installed.

 

the sound is now very impressive and hard to believe 

I am just amused by the irony of the fact that the "W" in LS50W stands for "Wireless". Just look at all of those wires you bought 😉. And , at prices in my country (UK), your upgrades would have cost more than the speakers did in the first place.

[bunno77]

33 minutes ago, PAR said:

I am just amused by the irony of the fact that the "W" in LS50W stands for "Wireless". Just look at all of those wires you bought 😉. And , at prices in my country (UK), your upgrades would have cost more than the speakers did in the first place.

That's why I named this thread "active". They aren't wireless like Dynaudios (obv need power cables)

[mourip]

On 9/18/2019 at 8:08 AM, wgb113 said:

Been away for a while - enjoying music and not worrying about gear!  Ran into an issue with my nearly 3yr old LS50Ws this past Monday.  Posted about it a couple of other places but figured I'd add it here as well:

 

First the stats:

• Manufactured 11/2016
• Running latest firmware.
• Approx. 150 - 200 hours on them.

Was listening to albums for about 3 hours on Sunday and everything was perfectly fine. Went to listen to an album Monday night and about half a side in it sounded like the left (slave) speaker’s woofer stopped working.

Played through the rest of the side (was needledropping) and then switched to the Optical input to rule out the Turntable and Phono Preamp as the fault. Used a mono CD and confirmed it was an issue with the speaker.

 

Checked the firmware version, it was up to date.

 

Disconnected and reconnected all source connection and the speaker-to-speaker cable.

 

Performed a Reset which did not work.

 

Unplugged both speaker’s power cords for a minute and reconnected. Everything was working fine again…for about a minute.

 

Unplugged just the slave speaker’s power cord - did not work.

 

Unplugged just the master speaker’s power cord - sound came back as normal…for about a minute.

 

Contacted KEF USA and they requested I send the speakers back which I’m doing today.  I’m obviously well out of the curiously short 1 year warranty at this point which is my reason for updating this post - to see how they deal with out-of-warranty repairs. I agree with the earlier poster that suggested KEF should have simply extended the warranty on all LS50Ws within a given production batch to at least 5 years (the standard warranty on the much-less complex passive speakers). They could have saved a lot of the bad feeling that have resulted as well as the hesitation prospective buyers feel when they come across the issues that are being reported.

 

As a big KEF fan I’m hoping they’re able to fix my pair at no extra charge other than shipping. I love the LS50W as it seems to me to be the fully-realized version of what they intended the LS50 to be (I lived with the passives for close to 4 years). I really don’t want to have to start a new search at this point, even though there are more options now than there were 3 years ago.

I’ll report back in about a month (they quote a 3 week turnaround time to diagnose and repair).

 

Hang in there. I helped a friend set up her LSX's. I believe that KEF powered speakers are one of the best values in audio.

 

I had her download a trial version of Roon and within days she proceeded to purchase the lifetime license. Add in Qobuz and you can explore new music forever without filling your home with CD cases or buying music that you did not know that you did not like!

[wgb113]

On 1/21/2020 at 9:15 AM, mourip said:

 

Hang in there. I helped a friend set up her LSX's. I believe that KEF powered speakers are one of the best values in audio.

 

I had her download a trial version of Roon and within days she proceeded to purchase the lifetime license. Add in Qobuz and you can explore new music forever without filling your home with CD cases or buying music that you did not know that you did not like!

All is well - KEF fixed them well out of warranty and all I paid was return shipping to them.

[mourip]

I broke down and bought a pair of LSX's last week to use as desktop speakers. I bought these from a KEF certified retailer as refurbished for just $800 all in.

 

Really remarkable considering that, especially if you have a Roon server on your network, these make a complete stereo. On my desktop I opted to drive them using their analog input coming from my Schiit Yggdrasil DAC. In my case this obviously does not take advantage of some of their "wireless" features but they sound remarkable. My DAC goes to 24/192 so I am also able to take advantage of a slightly higher resolution over the built-in DAC. I chose to connect them together using the ethernet "interconnect". In a different environment you could get great sound with just one power cable going to each speaker and Wi-Fi connectivity.

 

I wanted to buy the dedicated LSX desktop stands but they are WAY overpriced. Instead I just used some add-on rubber feet to raise the front of the speakers a bit.

 

 

[church_mouse]

54 minutes ago, mourip said:

On my desktop I opted to drive them using their analog input coming from my Schiit Yggdrasil DAC. In my case this obviously does not take advantage of some of their "wireless" features but they sound remarkable. My DAC goes to 24/192 so I am also able to take advantage of a slightly higher resolution over the built-in DAC. I chose to connect them together using the ethernet "interconnect". In a different environment you could get great sound with just one power cable going to each speaker and Wi-Fi connectivity.

 

 

 

 

Doesn't that mean you are doing 2 lots of conversions? I was told the internal dac cannot be bypassed - so analogue input gets converted to digital to be processed.

 

Is my understanding wrong?

[Cebolla]

8 hours ago, church_mouse said:

 

Doesn't that mean you are doing 2 lots of conversions? I was told the internal dac cannot be bypassed - so analogue input gets converted to digital to be processed.

 

Oh dear, if true. Makes sense, though, as I can't see how else other than in a digital format their audio could be kept in sync as a network connected stereo pair of devices - if that's what the connection actually is.

[mourip]

23 hours ago, church_mouse said:

 

Doesn't that mean you are doing 2 lots of conversions? I was told the internal dac cannot be bypassed - so analogue input gets converted to digital to be processed.

 

Is my understanding wrong?

Interesting. I had not heard that. If the connection to the slave speaker is digital then that would make sense. The analog input would be going through an ADC then.

 

The good news is that it still sounds very good but I will hook up a Toslink optical cable direct from my PC to compare.

 

Thanks.

 

Edit: I did just find a review in Stereophile that mentions that each of the four drivers has it's own DAC so this would certainly point to the extra conversion step for the analog input. A second review refers to the transparency of the analog inputs ADC...

 

[church_mouse]

I had read quite a few users reporting that they felt feeding to the analogue via an external dac sounded better. It was when I mentioned this to a dealer that he expressed surprise and informed me that the analogue gets internally converted to digital anyway.

 

Your experience of better sound quality does not seem uncommon, though why that should be may be harder to explain.

 

Happy listening.

[jcn3]

The analog inputs are converted to digital.  I've also heard that people find the analog inputs sound better, which seems strange given you can't bypass the internal dac (required for the internal dsp settings).

[DuckToller]

On 5/10/2020 at 1:02 AM, jcn3 said:

The analog inputs are converted to digital.  I've also heard that people find the analog inputs sound better, which seems strange given you can't bypass the internal dac (required for the internal dsp settings).

I've understood that in some Class-D designs digital inputs are not directed through DAC's anymore but routed through DSP into amplification. As an assumption, we are used to have certain preferences like i.e a slow roll off or apodizing filters. If we use an external DAC to the analogue input, these filters are in play.
Just an idea ...

[Tait]

Thought I'd revive this thread by describing the improvements that adding an Innuos Phoenix has done to my LS50's and MK2 Zenith server setup.

 

The improvement is not subtle.

Soundstage has improved by quite some margin, instruments now seem to have their own space; the noise floor has dropped as I'm hearing things which I've never heard before; timing has improved (feets tapping a lot more!); The top end has a lovely shimmer to it.

 

Yes it's expensive, but having listened to it for a few weeks now, I can say it's the best upgrade I've made.

 

Definitely worth a look for anyone that has the KEFs but is looking to improve the sound even further.

[bunno77]

5 hours ago, Tait said:

Thought I'd revive this thread by describing the improvements that adding an Innuos Phoenix has done to my LS50's and MK2 Zenith server setup.

 

The improvement is not subtle.

Soundstage has improved by quite some margin, instruments now seem to have their own space; the noise floor has dropped as I'm hearing things which I've never heard before; timing has improved (feets tapping a lot more!); The top end has a lovely shimmer to it.

 

Yes it's expensive, but having listened to it for a few weeks now, I can say it's the best upgrade I've made.

 

Definitely worth a look for anyone that has the KEFs but is looking to improve the sound even further.

Very happy this thread is still going. I still don't own them but have heard them quite a few times now.

 

Can I ask if you have compared this to using the ethernet input ie Roon/DLNA etc via ethernet

[erniejade]

  I can hear  the difference  between using my nas direct to the kef and going through the analog rca from my lumin.  Same ripped cd, same storage place, different source delivery does make a sound difference.  

 

I also have a schiit sys so i can bounce between my lumin and jolida d9 tube phono pre.  Each source has a different sound even though  it gets converted from the kef. It keeps the source  sound or sonic signature of the device nicely 

[Richard Dale]

5 hours ago, Tait said:

Thought I'd revive this thread by describing the improvements that adding an Innuos Phoenix has done to my LS50's and MK2 Zenith server setup.

 

The improvement is not subtle.

Soundstage has improved by quite some margin, instruments now seem to have their own space; the noise floor has dropped as I'm hearing things which I've never heard before; timing has improved (feets tapping a lot more!); The top end has a lovely shimmer to it.

 

Yes it's expensive, but having listened to it for a few weeks now, I can say it's the best upgrade I've made.

 

Definitely worth a look for anyone that has the KEFs but is looking to improve the sound even further.

I only use my LS50s and subwoofers with a wireless connection as it is really a ‘lifestyle’ system although on a large scale and I don’t want to have computers, USB cleaner uppers etc adding clutter. On the other hand having said that, I’m interested in what sort of scale the delta is between a high end USB input like you have, and a wireless music connection via UPnP.

[Tait]

22 hours ago, Richard Dale said:

I only use my LS50s and subwoofers with a wireless connection as it is really a ‘lifestyle’ system although on a large scale and I don’t want to have computers, USB cleaner uppers etc adding clutter. On the other hand having said that, I’m interested in what sort of scale the delta is between a high end USB input like you have, and a wireless music connection via UPnP.

 

I've never listened to my KEF's via wireless so can't comment there, but the difference between streaming natively via the KEF app and my Innuos setup really is night and day.