Beolab 5. When you need help with your ICE module

[Beobuddy]

When you think that you’re having a faulty ICE module(s) in your chassis and as they aren’t available anymore (except for extremely high prices), I’ve made the effort to get them most reliable working order again.

I’ve spent some considerable amount of time (and means) lately to fix ICE power amplifier modules from the Beolab 5 and Beolab 2. Made a test environment to measure and test the modules thorougly.

Throughout the past years I’ve collected these modules and fixed lots of them and noticed that the culpritt can be on different places on the board. So I decided to fix a pile of modules and marked and made notes of each module. That way I’ve collected notes over 60 modules with at least 15 positions they can fail and got a pretty clear view which components fails the most and some less.

This way every module can be reliable fixed when changing every possible weak component.

 

Keep in mind that a Beolab 5 (just as every other electronic product) can fail on more different internal parts, but with the knowledge that they can be repaired, my personal resistance to buy a set secondlife decreases significant.

So, if you’re considering a pair of BL5’s. Just do it.

After all, they sound amazing and have an unique appearance.

[Hyponx]

Beobuddy this is an awesome post. It’s fantastic to see repairs at this level for Beolab speakers in general.

I have dreamed of buying a pair of Beolab 5 personally but have worried about the issue of repairing the chassis. This adds considerably to my confidence in proceeding.

Assuming you offer repair services do you have a website/contact info and wherebout are you located in the world?

Cheers,

Hyponx

[kirin]

I agree, that is fabulous!

Are there – according your experiences – different behaviours, probabilities to be faulty given, when comparing MK1 and MK2 models?

[mhenryk]

Hi @beobuddy,

My name is Henryk. I 100% agree with your statement: Beolab 5 sound amazing and have a unique appearance. To the point that recently I acquired pair of them (vintage 2007). They indeed deliver.

One of those speakers is perfectly fine.

The other one, I think, starts to exhibit issues that will cause repair effort in near future. Here is what I noticed so far

1. It takes considerably longer time for it to finish autocalibration procedure (compare to working specimen)
2. It stops reacting to commands from Beosound 9000 (It will react to wake up command but once operational the only way to power it down would be thru power cycle)
3. It might be just my impression but it could be getting warmer compared to working specimen (judging by heatsink temperature at the back)
4. If it gets warm if won’t start again even after power cycle. It needs to be left powered down to cool down for half an hour or so, and then it will start again.

This is what I noticed so far. It feels like there is an issue with its power supply that starts to affect stability of the system but I might be completely wrong. Here is where I hope you can help me.

If you could guide me what could be done next to service/fix this speaker that would be very much appreciated. I only have access to what is widely available on the internet which is service manual.

Since schematic, PCB files or BOM are not available, I would work completely blind here which might not be a good idea. In the past I did this: https://www.youtube.com/watch?v=MFGvZFi11Zc therefore I should be able to work on this system with some guidance from someone who knows 🙂

If possible, please share your suggestions how we can proceed here.

Thanks for your time,
Henryk

 

[mhenryk]

Hi @beobuddy,

One more observation from my side. If speaker that exhibits unstable behaviour is cold (in power down state) and I power up whole audio system it works as expected. There are no issues with reacting for commands from Beosound.

Issues starts to appear when speaker runs for number of hours and I guess its guts to higher temperature.

Is there a chance that some sort of thermal paste that should be present between components and their heatsinks is gone after 15+ years and this causes some issues?

Any guidance is highly appreciated.

Thanks for your time,
Henryk

[Gunter Gerber]

Hi there,

I‘m a new member here, but a longterm lover and owner of B&O products.

Starting in 1997 with BV28, BL8000 and later on BS9000. In 2000 BL1 and 2013 a dream came true: used BL5 from a B&O shop, SN 206…. & 207… SW 2.6

I updated TV and audio with an ‚almando‘ electronic, run without any problems till 2020: one BL5 chassis repair. The second BL5 get a new chassis in 2023. There are sound scratches, my description, and the B&O dealer send it to Denmark. I had to pay a big ticket, twice.

So, now, since 2 weeks, I miss the deep tones :(, the auto bass meassurement didn’t work,  stop every time, pressing 25sec the top or unplug power for more than 10min doesn‘t help.  I’vve read a lot, before I found you here.

Before I go to the dealer again, is it posssible to get help/repair here? I‘m a prof. IT guy since 35 yrs and think, with the service manual in hand, to dismantle the BL5

@beobuddy could you help here? seems you helped a lot, may me too?

thanks in advance

Gunter

p.s. sorry for my english, it‘s rusty after not working in english envireonments

[mhenryk]

Hi @marexy

Looking thru forums for Beolab 5 success stories I came across you.

Did you manage to fix yours Beolab 5? What I wrote above still stands. At this point I basically completely powered down one of my Beolab 5. It is not completely dead but it feels like it is on its way out.

Do you have any advises where to start repair of those speakers? Which components are mostly faulty? What to pay attention to? What to check (inside) using scope, etc?

I guess there is no way to get schematic or layout or BOM for those speakers therefore any advice that could be shared here how to proceed with potential work to fix them would be very much appreciated.

Thanks,
Henryk

 

[marexy]

Like Beobuddy for some time now i rapired lots of Icepower moduls beside other repairs on B&O systems.

BL 3, 4, 4000 Mk2, Bl2, BL5, BL11, BL7, …ect..

There are no same faults. And here and there some crazy suprise error.

Or some reapir faliure from DIY repair projects.

 

[mhenryk]

Hi @marexy

Thanks for note.

How do you start such repair? Are you looking for voltage levels based on block diagram or something? Any guidance where to start and what to pay attention to when doing so?

Thanks,
Henryk

[Beobuddy]

@ Gunter.

Does calibration starts with the microphone coming out? If not, then there is another problem.
Most of the time the ICE amplifier for the lower bass is the culprit. But again, look at the movement of the microphone.

[Beobuddy]

mhenryk wrote:

Hi @beobuddy, One more observation from my side. If speaker that exhibits unstable behaviour is cold (in power down state) and I power up whole audio system it works as expected. There are no issues with reacting for commands from Beosound. Issues starts to appear when speaker runs for number of hours and I guess its guts to higher temperature. Is there a chance that some sort of thermal paste that should be present between components and their heatsinks is gone after 15+ years and this causes some issues? Any guidance is highly appreciated. Thanks for your time, Henryk

Temperature is an issue, but not due to old thermal past. If the BL5 doesn’t respond to instructions, then it is most likely caused by the processor on the DSP board. And that is a challenge as the processors on mk2 and mk3 are covered by a layer of resin or some sort of.

[Beobuddy]

It takes a serious amount of time (and money) to create steady and reliable environment to test and repair modules and BL5’s. To fix a ICE module with just a multimeter will help you, but for more reliable results you need to test them for a longer period of time.
And even despite all the equipment I have,  I don’t have all the (software)tools that B&O has when it comes re-program DSP boards.

[mhenryk]

Hi @beobuddy,

Speaker type is 6881 with SW 2.6 (not sure which revision of speakers this is mk1, mk2 or mk3).

Yes, speaker stop responding to remote controller commands once it gets warm (after 1..3 hours of normal operation – no loud audio there).

I can certainly check if micro is covered with something but how do you draw any conclusions out of it?

How would you go about fixing something like that? Do you offer service to fix it?

Thanks,
Henryk

 

[Beobuddy]

And for testing ICE’s and chassis for a longer period and more heavy load, I have a dedicated BL5.

At the picture you can see the custom made extension cable between the chassis and the loudspeaker itself with the same connectors used by B&O to achieve that reliable connection.

All, again, to get the most reliable test environment and result.

[Beobuddy]

mhenryk wrote:

Hi @beobuddy, Speaker type is 6881 with SW 2.6 (not sure which revision of speakers this is mk1, mk2 or mk3). Yes, speaker stop responding to remote controller commands once it gets warm (after 1..3 hours of normal operation – no loud audio there). I can certainly check if micro is covered with something but how do you draw any conclusions out of it? How would you go about fixing something like that? Do you offer service to fix it? Thanks, Henryk

A BL5 with software 2.6 printed on the label underneath the big disc, is a mk2. mk1’s have software 1.4 or higher, mk2’s have software 2.6 or higher and you can quess that software 3.0 or higher is a mk3. But  Afaik there are mk1’s with newer revisioned chassis with upgraded software. But not sure about that. I have seen different components on the mk2 and mk3 when you compare them side by side. I tend to think that mk3’s are a bit more vulnerable for malfunctions. I’ve fixed some mk3 boards on places I haven’t seen happen on the mk2 series.

But to answer your question, I offer the service. But.  At this moment I’m still examining these kind of behaviour. Due to the fact that the BL5 needs both data and the trigger signal  to operate, I’m leaning towards the processor or something in it’s surrounding area. But as these are covered with a special hardened fluid, it is still impossible to measure. It wouldn’t suprise me if there is something happening as with the early BS9000mk1’s and some mk2’s where the processor itself might be the culprit.

[Gunter Gerber]

Hi beobuddy,

I started just now a again. pressing the top for a few seconds, the LED starts blinking green, the micro comes out…. but nothiing happend. after a short time, no sound and the micro drives back, LED is blinking red.

As I remember, when I got the seaker, the procedure starts like now, but there are different soundings to hear, the micro comes more out after the test – test done. What I did‘nt understand, both speakers running in the same way

Thanks for any idea

 

p.s. I  just  got an offer  for  a  set  og  MK3, SW 3.0, serial 2153…. for €6750, model 6881, but from a private person sayinmg the are  from 2012. What do you think about?

 

[Daniel Duesentrieb]

With my Beolab 5’s one of the two 1000W amplifiers failed in each speaker after about 15 years. My dealer sent the compelete electronic modules to B&O Denmark where they became renewed, costing 1200 – 1300 Swiss Francs each. Work fine again.

[Frog]

One of my Beolab 5 has gone faulty. What happens is that when switched on, it emits a tone (sort of mid-range) then cuts off and the light turns to a flashing red.

I’ve left it off for an hour or so, but still has the same ‘feature’

what could be the diagnosis – worst case, I’ll have to have the chassis replaced – in which case I’d do the pair just in case.

[Hyponx]

Hello Beobuddy,

I hope your search for the source of the BL5 issues is successful as I think it is critical to the longer term preservation of these beautiful speakers.

You mentioned this coating on part of the DSP board. I noticed that Kose Trading has a picture of a board that doesn’t have this coating. It’s not perfect but might be just enough.

I see a H8S/2240 microcontroller IC, the other is harder to make out, but I think its an SST 39SF040 which is a CMOS Multi-Purpose Flash chip. My bet is this is where the ABC calibration results are computed and then live, (maybe also the pin code?). This may be at the heart of that failure.

It does seem like there are at least two revisions of this board I’ve seen B6143219 and B6143575

I also came across this post on a forum from some kindred spirits trying to troubleshoot issues on a BL5.

Good fortunes out there and thank you.

– Hyponx

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