So, with this new white obsession of mine, I've started to get a little more detailed...

Custom white audio cables 😐

Once I get back inside of these pieces for the recap, I'll be adding white power cords as well.

Evan, please stop with your white obsession, you already have infected me😁

Leslie wrote:

Evan, please stop with your white obsession, you already have infected me😁

The Beovirus has mutated into Beowhitevirus[😂]

Evan wrote:

So, with this new white obsession of mine, I've started to get a little more detailed...
Custom white audio cables.
Once I get back inside of these pieces for the recap, I'll be adding white power cords as well.

Evan, I LOVE what you've done to your Hot-Rod Beosound 4500 "Custom".
The minute attention to details makes your system stand out! It is this attention to deatil that separates a "Show Winner" from the other Hot-rod wannabees!

BTW, after reading this thread I decided to order a few veneers from Alsa corp to try on some older B&O units, just in case.

I'm in the middle of restoring a recently purchased BM4500 and BG4500CD for our guest room, both have loose panels.
Your detailed panel work-flow is my visual service manual... Fortunately the mirror finish is in "As New Condition" on both.

Did you by any chance open up the bottom of the unit to see the bottom of the PCBs?
Mine show two "hot spots" on the Power-supply & Output Amplifier PCB: "Diagram C"

If you don't see/didn't see this, has anybody else seen this? Should I worry?
BM starts and works fine as is, but I don't know if this is normal or foreboding an imminent failure?

Any suggestions?

IkeA wrote:

Mine show two "hot spots" on the Power-supply & Output Amplifier PCB: "Diagram C"

If you don't see/didn't see this, has anybody else seen this? Should I worry?
BM starts and works fine as is, but I don't know if this is normal or foreboding an imminent failure?

These are both areas that handle large currents (the other one is under the rectifier diodes, the other one seems like a regulating stage) and therefore generate quite a bit of heat in normal operation. The circuit board material will darken with age around such hot spots. I wouldn't worry.

tournedos wrote:

These are both areas that handle large currents (the other one is under the rectifier diodes, the other one seems like a regulating stage) and therefore generate quite a bit of heat in normal operation. The circuit board material will darken with age around such hot spots. I wouldn't worry.

(Kiitos vastauksesta)

Thanks for the feedback re darkening of PCB.
I was thinking of replacement of components with higher current ratings (diodes) and higher watt rating (resistor), to lower the heat production and heat related aging.

What would be the most efficient way to minimize or eliminate this heating problem, or is this a "go back to sleep"/in my head only, problem? Is the current load much higher when running Beovox speakers on this amp?
Would this still be a problem if the BM4500 was used only with Beolab speakers?

Thanks for all inputs.

IkeA wrote:

What would be the most efficient way to minimize or eliminate this heating problem, or is this a "go back to sleep"/in my head only, problem?

As I said, don't worry 😕 The amount of darkening I see in the pics is not a problem, it's quite normal.

You can replace some components with higher rated ones and/or install them farther away from the PCB surface, but it won't affect the generated heat a bit. The same amount of power is still being dissipated.

Some folks like to replace the rectifier diodes with schottky types (lower forward voltage drop -> lower dissipation), but I see no point in that here as this is not a known problem spot, and the original setup will probably last a lifetime anyway.

You're right that running passive speakers will use more power in the amp itself and thus the main power supply. However, at normal listening volumes the difference will be only a few watts, and again, I just wouldn't care. It's just being used as designed!

IkeA wrote:

Evan, I LOVE what you've done to your Hot-Rod Beosound 4500 "Custom".
The minute attention to details makes your system stand out! It is this attention to deatil that separates a "Show Winner" from the other Hot-rod wannabees!

Hello IkeA, thank you for your wonderful comment!!! I am also delighted that my thread has been able to assist you 🙂

Come to think of it, I never did look at the bottom of my BeoMaster. It was in 100% perfect working order so I didn't bother. At first, your pictures did alarm me but Mika's comments calmed me down! 😂

I do have plans to resume this thread and do a technical restoration this summer. I want my amp in top spec because I have this crazy idea of adding more speakers...

I thought I would inform you all that the white strain of the BeoVirus has mutated again! This disease is widening its reach! Warning, Apple gear may worsen your infection!

exquisite ?

or should I say exquisite ?