BM 8000 new owner, fault

[Davide Frada]

Hello from a new member, but long time B&O owner and admirer.

Yesterday I was finally able to purchase a BM8000 with the hope of pairing it with my MS150.2s. There is a catch – the 8000 doesn’t work.

When I viewed it, it was powered up and showing 9.9 for volume, 7 in the centre display, and 7 on the right display. There was no hope of further testing (no cables/speakers/etc), but made the purchase anyway.

Once home and plugged in, I was able to see what I believe to be the standby light, some relay clicking, as well as “manual” in the bottom right, which comes and goes based on the relevant switch. Turning a set of speakers on with the top switch gave me a gentle hiss which at least shows the amps are doing something. Shortly after, it lost the standby light, and the 4A fuse was found to be blown.

I have found circuit diagrams and have familiarised myself with disassembly. There are a few service stickers on the back, and the output boards appear to have had some replacement caps.

I didn’t bother replacing the fuse as I at least want to replace the rather sad looking RIFA cap in the start up circuit (cracked, but not yet exploded).

Do the particular numbers it was displaying hint to the nature of the problem? I understand they have a test sequence.

Any hints would be much appreciated

 

 

[Dillen]

Could be a lot of things – and possibly a combination of power supply ripple, cracked solder joints, flaky connector pins and perhaps something more.
It’s safe to say that all Beomaster 8000s will need a complete overhaul by now, capacitors, trimmers, adjustments etc. if
not already done.
And they are worth it.

Martin

[Davide Frada]

A little bit of an update –

I replaced the cap on the 5V supply, which was cracked.

I replaced the insulator card over the power supply, which had been mislaid.

The clipping wire was attached to earth – I placed it back to where it should be.

I started it up with the outputs disconnected to be greeted with a good working display, no dead segments etc.

Reconnected the outputs and tried again, to be greeted with sound. I just had little x25s attached, so the sound was nothing remarkable.

I won’t hook it up to the MS150.2s until after I replace the fuse board RIFA.

The unit has three service stickers on it and I notice the power amp trim pots have been upgraded. Some original caps remain.

On that basis I’m tempted to just push it into service, pending RIFA replacement.

 

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