Opening the LS50s

[killdozzer]

SOME GOOD NEWS, FINALLY!!

It worked for half the problem. Here's the update step by step:

This is a docking I made to prevent cone touching a hard surface. This way It was suspended in air 1/3 of an inch above the working table.

The driver is suppose to go into the middle square, obviously, thus:

Only then did I start unscrewing the screws and by the smart advice from @Swerd, I color coded the connections:

It is hardly visible, but there's a blue mark inside the red circle in the pic.

 

[killdozzer]

These were some of the worlds slightest taps With a pencile that has a rubber eraser and I used it as a precaution to avoid any further damage:


I admit, I didn't make the indent completely invisible, but I'm satisfied and will leave it at this. I did, however make it much less visible and it was a small indent to begin with.

Now I'm waiting to hear from @TLS Guy to see whether I can spot a loose VC.

One other thing that raises hope is that one cable was placed against the inner side of the speaker wall, exactly where I was hearing the buzz (the red and black one went between the sponge and the MDF rather than being in air and touching nothing but sponge).

The speaker is open now and my fingers crossed:


In this last pic you can see the red and black wire moved to the center. Before it was to the left between the black sponge and the side wall. I really, really hope this is the cause.

 

[killdozzer]

My tips for LS50's owners:

I found removing the baffle to be safer in order to avoid handling the driver directly as it is surprisingly soft. When you have the whole baffle, you can hold it by the baffle.

But, bare in mind that the rubber screw covers are fixed with some sort of resin so they WILL brake of and you'll need new ones if you want to put everything back together as it was.

Be careful, there's not much connection cable length. You'll have to detach it with one hand while holding the box with your other hand. Or provide something for the box to lean against as it is impossible to fully open it and put it aside while the driver is connected.

The connections have security stops. You can't just pull them of. There's a small lever you have to push first making it even more difficult to do with only one hand. So do find something for the box or ask someone to lend a hand.

My indent was very small so slight tapping from the opposite side did the trick. I DON'T think, however, this would be possible with bigger damage.

 

[PENG]

Thnaks @Johnny2Bad
This is the only reason I'm still suspicious about what @TLS Guy stated might be the problem. You can only hear it at that one spot and you have to be not further than 2 feet.

Come really close to the front baffle and you will not hear the buzz. Odd, I know.

That sounds 100% logical to me, not loose VC then, a good thing.

 

[PENG]

In this last pic you can see the red and black wire moved to the center. Before it was to the left between the black sponge and the side wall. I really, really hope this is the cause.

Another logical thinking, I think you got the problem solved. If that turns out to the the root cause, you should have taken a better photo and send it to KEF and complained about their workmanship and QA procedure. You should ask for one replacement speaker, link them to this thread to give them the incentive. They should thank you. But to be clear, what I am saying is only relevant if in fact the lead was touching the cone causing the buzz.

By the way, just to be sure, did you open the back or you actually removed the front baffle?

 

[<eargiant]

Never take advice from an idiot.

^^^This coming from the guy who just voided his 5 year factory warranty and has yet to solve the most critical issue. Priceless.

Even though you remain true to form with your reply, I hope it's the wire as you suspect and you solve your issue. Then you can feel free to ignore the advice of an "idiot" like me and run them full-range. Let's see a video of you running them well below their specified limits, how about ~94-96 dB SPL with bass or midbass heavy content. Do you have the balls to do that especially now that KEF will never- ever cover anything that goes wrong with that speaker. Let's see you put your money where your mouth is and ignore the advice of an "idiot".

If that turns out to the the root cause, you should have taken a better photo and send it to KEF and complained about their workmanship and QA procedure. You should ask for one replacement speaker, link them to this thread to give them the incentive. They should thank you.

He should have filed a claim right from the start. It's too late for that now, as soon as he opened and tampered with the speaker the warranty went bye-bye. That's a 5 year warranty down the drain. Actually sending KEF a link and proof of what he's done is only going to weaken his case.

(D) WARRANTY COVERAGE AND LIMITATIONS

This warranty does not cover any of the following:-

7. any KEF Product and/or any of its components which have been installed, disassembled, repaired, converted, modified, tampered with or otherwise interfered with in any way by any person/entity other than an authorised representative of the KEF and its Authorised Distributors

 

[William Lemmerhirt]

This post has no actual value other than my impressions of the linked song. I just listened to it in 7.3 and can’t imagine listening to it without subwoofers. And no I’m talking about some trunk rattling car audio junk. I mean, there is a lot of texture in the bass region and I’m pretty sure I heard a couple dips into the low 30’s. Pretty cool song.

 

[KEW]

This post has no actual value other than my impressions of the linked song. I just listened to it in 7.3 and can’t imagine listening to it without subwoofers. And no I’m talking about some trunk rattling car audio junk. I mean, there is a lot of texture in the bass region and I’m pretty sure I heard a couple dips into the low 30’s. Pretty cool song.

I just listened to it on Philharmonic BMR's (a known and respected quantity... -2dB @ 32Hz).
There is plenty of very deep bass that left me wondering if I was missing anything - would additional content be added with a good sub? Definitely has very low frequency content for music.
Did not notice any inappropriate noises (aside from distortion in her voice ... "sorry" @1:55, for example). However, I did not leave my listening position to see if there were any untoward noises in closer proximity to the speaker.
It does seem like a pretty good torture test for most speakers to determine how well the speakers can handle very low frequencies (or if things are not properly secured)!
I enjoyed the song, but moreover, I recognize it as a song that really requires good speakers! It goes deep, but not in the way club music does.
As you said, it has textured bass. Consequently, it needs to be played back on a system capable of that texture. When I play it on my Monsoon 2.1 PC system, the "subwoofer" definitely loses composure! There is still enough content that I get a very strong sense I am missing a lot! This is what led me to take it to the BMR's.
It is reassuring to see modern music that has low bass and demands high quality reproduction to capture the full effect in this "earbud/bluetooth speaker world"!!!

@killdozzer , how does this work on the LS50's (after the wire to cabinet vibration is fixed). Do you run a sub with it? Among "smallish" speakers, I would expect the LS50 to pretty much be "as good as it gets"!

This is music I like and I know my GF would love it; however, she listens to most of her music using an Edifier BT speakers system. It is very good for what it is, but their 5" (?) mid-woofers are only going to highlight that the music is not complete!
It's frustrating, maybe a subwoofer is in order for Christmas!

 

[William Lemmerhirt]

I just listened to it on Philharmonic BMR's (a known and respected quantity... -2dB @ 32Hz).
There is plenty of very deep bass that left me wondering if I was missing anything - would additional content be added with a good sub? Definitely has very low frequency content for music.
Did not notice any inappropriate noises (aside from distortion in her voice ... "sorry" @1:55, for example). However, I did not leave my listening position to see if there were any untoward noises in closer proximity to the speaker.
It does seem like a pretty good torture test for most speakers to determine how well the speakers can handle very low frequencies (or if things are not properly secured)!
I enjoyed the song, but moreover, I recognize it as a song that really requires good speakers! It goes deep, but not in the way club music does.
As you said, it has textured bass. Consequently, it needs to be played back on a system capable of that texture. When I play it on my Monsoon 2.1 PC system, the "subwoofer" definitely loses composure! There is still enough content that I get a very strong sense I am missing a lot! This is what led me to take it to the BMR's.
It is reassuring to see modern music that has low bass and demands high quality reproduction to capture the full effect in this "earbud/bluetooth speaker world"!!!

@killdozzer , how does this work on the LS50's (after the wire to cabinet vibration is fixed). Do you run a sub with it? Among "smallish" speakers, I would expect the LS50 to pretty much be "as good as it gets"!

This is music I like and I know my GF would love it; however, she listens to most of her music using an Edifier BT speakers system. It is very good for what it is, but their 5" (?) mid-woofers are only going to highlight that the music is not complete!
It's frustrating, maybe a subwoofer is in order for Christmas!

Hey Kurt, nice reply!
I can’t say for sure if you’d me missing anything with the BMR’s. For one reason I don’t know for sure how low this song goes. I have response down to about 14hz with a natural room bump centered at 16. To my ears, I think I noticed some material in the 30hz range. It was quick so It was hard to tell, and it could easily have been on either side of 30. My natural inkling is yes, a sub would add something to the experience for you. Maybe not a lot though. Im sure the feeling you got listening to this in the smaller system of something missing was almost gone on the BMR’s. Tough question.
My mains are rated somewhere in the 32-35(have to look) range and I haven’t tried the song in “direct” mode, but even though they measure very nicely down low, the inclusion of my subs just adds weight and atmosphere to the bottom of music of this style, which I also enjoy. This could be because of my concrete floor not sure.
I also didn’t hear anything objectionable and totally agree this is a pretty wide dynamically ranged song. A good test indeed.
I do also believe your girl should get a sub for Christmas!

 

[TLS Guy]

Hey Kurt, nice reply!
I can’t say for sure if you’d me missing anything with the BMR’s. For one reason I don’t know for sure how low this song goes. I have response down to about 14hz with a natural room bump centered at 16. To my ears, I think I noticed some material in the 30hz range. It was quick so It was hard to tell, and it could easily have been on either side of 30. My natural inkling is yes, a sub would add something to the experience for you. Maybe not a lot though. Im sure the feeling you got listening to this in the smaller system of something missing was almost gone on the BMR’s. Tough question.
My mains are rated somewhere in the 32-35(have to look) range and I haven’t tried the song in “direct” mode, but even though they measure very nicely down low, the inclusion of my subs just adds weight and atmosphere to the bottom of music of this style, which I also enjoy. This could be because of my concrete floor not sure.
I also didn’t hear anything objectionable and totally agree this is a pretty wide dynamically ranged song. A good test indeed.
I do also believe your girl should get a sub for Christmas!

I have analysed that video for you.

There is a lot of bass content with a lot of energy right out to 20 Hz.

The peak energy band is 170 Hz to 350 Hz.

For some reason a brick wall filter has been employed at 12 KHz where the response falls literally off a precipice.

The introduction is not clean. These is distortion and even crackling fuzz, it seems to be centered on the 170 to 400 Hz pass band as it modulates with those frequencies. Whether it is intentional or not I have no idea. I do note that they keep the bits highly saturated all the way through which is not good technique. So it is possible they ran it out of bits. After the 1 minute mark all this clears up and the rest of the recording is clean.

I note on the phase scope, there is not much stereo spread, so it is heading to double mono territory.

There is a lot of the sloppy technique prevalent in the pop industry in play here.

After the 1 min mark the recording is clean however.

Certainly there is enough bass energy to cause distress and damage to a lot of smaller drivers.

The sort of spectrum is what I usually see from large pipe organs at full cry using all the stops. Although those instruments produce a lot more high energy and stress tweeters as well as woofers.

 

[PENG]

I have analysed that video for you.

There is a lot of bass content with a lot of energy right out to 20 Hz.

The peak energy band is 170 Hz to 350 Hz.

For some reason a brick wall filter has been employed at 12 KHz where the response falls literally off a precipice.

The introduction is not clean. These is distortion and even crackling fuzz, it seems to be centered on the 170 to 400 Hz pass band as it modulates with those frequencies. Whether it is intentional or not I have no idea. I do note that they keep the bits highly saturated all the way through which is not good technique. So it is possible they ran it out of bits. After the 1 minute mark all this clears up and the rest of the recording is clean.

I note on the phase scope, there is not much stereo spread, so it is heading to double mono territory.

There is a lot of the sloppy technique prevalent in the pop industry in play here.

After the 1 min mark the recording is clean however.

Certainly there is enough bass energy to cause distress and damage to a lot of smaller drivers.

The sort of spectrum is what I usually see from large pipe organs at full cry using all the stops. Although those instruments produce a lot more high energy and stress tweeters as well as woofers.

I can't say this often enough, assuming the media player or streaming devices are good, it is the source recording/mastering that matters most to sound quality, followed by source recording/mastering, and then source recording/mastering...after those 3 things, then the speakers, the room and then the preamp/power amps..maybe... Speakers and amps, and DSPs are not recycling plants, so garbage in garbage out applies.

 

[William Lemmerhirt]

I have analysed that video for you.

There is a lot of bass content with a lot of energy right out to 20 Hz.

The peak energy band is 170 Hz to 350 Hz.

For some reason a brick wall filter has been employed at 12 KHz where the response falls literally off a precipice.

The introduction is not clean. These is distortion and even crackling fuzz, it seems to be centered on the 170 to 400 Hz pass band as it modulates with those frequencies. Whether it is intentional or not I have no idea. I do note that they keep the bits highly saturated all the way through which is not good technique. So it is possible they ran it out of bits. After the 1 minute mark all this clears up and the rest of the recording is clean.

I note on the phase scope, there is not much stereo spread, so it is heading to double mono territory.

There is a lot of the sloppy technique prevalent in the pop industry in play here.

After the 1 min mark the recording is clean however.

Certainly there is enough bass energy to cause distress and damage to a lot of smaller drivers.

The sort of spectrum is what I usually see from large pipe organs at full cry using all the stops. Although those instruments produce a lot more high energy and stress tweeters as well as woofers.

Mark, thanks for diving into that. I was pretty that track got below 30 but surprised it went all the way to 20. I will listen again with more volume and without my family in the room. I was only at -20.

My guess is the distortion you noted was intentional, as it somehow seems to play along with the vibe of the song. However we’ll probably never know.

I agree, there’s a lot of bass energy, and I would be nervous about running too many BS speakers at any high volume. Curious to run my mains in direct with it though. I’m interested in some pipe music too. If I ever get any time to myself I intend to enjoy some.

 

[killdozzer]

For a few days I must have been the luckiest man alive!!

It worked! It worked like a charm. My speaker is back in it's proper (and heavenly for me) working order.

Moving the wire away from the inside box wall obviously did the trick. (Unless I did something else unintentionally).

I've straightened the indent along the way. I didn't put even one scratch, not even a hairline scratch on the piano finish.

Thank you all for your wisdom, patience and knowledge you shared with me. Hopefully, this adventure of mine might help someone else if he finds himself in need.

One more thing: I'm writing of this song that I linked as a heavy load, a good test run for a speaker and nothing to sneeze at for many of the poorer designs. The demanding nature of its production revealed something I could, fortunately, mend on my own. After that, speakers played with next to none distortion even when I used Dolby to further enhance the lows (so, really stressing it).

Since it's playing nice now (windows start shaking and making buzz before I notice anything from the speakers),I'm done with these tests.

Conclusion: What I found out about myself is that I'm more of bass-head than I would ever thought. It seems that a solid SW made for music is a must for me, regardless of the fact that my listening room is just under medium size.

The tempest died out, I'm safe on the other side.

 

[PENG]

I didn't put even one scratch, not even a hairline scratch on the piano finish.

Amazing! You are obviously highly talented!

Thank you all for your wisdom, patience and knowledge you shared with me. Hopefully, this adventure of mine might help someone else if he finds himself in need.

Now I have less fear about failure after warranty.

Conclusion: What I found out about myself is that I'm more of bass-head than I would ever thought. It seems that a solid SW made for music is a must for me, regardless of the fact that my listening room is just under medium size.

Like @ADTG, depending on your room, Audyssey may not be for you then. In my room, Audyssey flatten the 18-125 Hz range, and that resulted in an average of 7-10 dB between 18-30 Hz and another 3 dB or so between 70-125 Hz.

 

[Johnny2Bad]

Great news, Killdozer. Back to enjoying the music ...

 

[killdozzer]

Amazing! You are obviously highly talented!

I wouldn't really say that, rather that I'm cautious. Once I separated the box from the baffle, I moved the box away from the working station until assembly. I did think the entire process of trying to fix the speaker through numerous times. All the ugly scenarios went through my head, must have prepared me. Like, what if it starts falling from my hands and I instinctively grab it by the membrane or what if I brake the inner bind where the wire gets connected to the driver and so on.

Like @ADTG, depending on your room, Audyssey may not be for you then. In my room, Audyssey flatten the 18-125 Hz range, and that resulted in an average of 7-10 dB between 18-30 Hz and another 3 dB or so between 70-125 Hz.

A good one!
I'm still saying, I think my room reinforces the lows a lot. I can't wait to do the measurements and post them here. I think a lot of people here will be surprised how low they perform in my setting. My plan (which can change thousand times over) is to use the SW to redistribute the tasks. I want to alleviate some of the burden from the monitors. That's why on one occasion I was asking you about higher XO.

Great news, Killdozer. Back to enjoying the music ...

Exactly! Thank you Jhonny2Bad. They're playing around the clock.