I tried using Beomaster 5000 as a preamp, but it did not work, I got a loud hum from the speakers. Is there something wrong here? Can anyone help with this please.

 

Cheers

How do you have it hooked up? Which output conections are you using?

I connected RCA output marked as Preamp of 5000 and the other end of those went into a power amp. But no sound got loud hum only.

If the BM is otherwise working, it would seem like a bad etch or loose connection to the preamp outputs. It would seem very odd to have both channels having that problem. Is the receiver working fine otherwise?

Yes other then that the unit works perfectly, if you look at the on line manual, in order to use this unit as a preamp, you need some kind of beo swithch type 4002 which would go to the relay input in the back of 5000 and would allow you to use this as a preamp.

How do you have your connnected as a preamp?

 

Cheers

 

The 4002 switch unit is really an accessory power outlet. It is triggered by the power on the BM so you can power another unit like an amplifier at the same time. It does not activate the pre amp outputs.

After reviewing the service manual, there seems to be more than just a plug lead involved. A portion of a shared chip (IC3) is in use to drive the preamp output, but it seems unlikely the chip would be bad since it seems to work fine when the other portion is in use to drive the output stage. I think you'll need some assistance from folks more experienced in this than I am. Good luck.

That chip carries the same signal that goes to the power amps. If the Beomaster plays fine by itself, there's nothing wrong there.

After that, the preamp outputs are essentially a resistor and an RCA socket. There really isn't a lot that can go wrong, apart from the sockets having broken solderings. Not unheard of, but I would concentrate on the external cabling and the other amp before going in there.

All the switch unit does is help power on & off external devices. It's not needed for this to work.