Anyone?? What Could be wrong

6 replies

One of my BL4000 is making a loud hummm when powered on. I coudl eliminate following by trial and error

1. Powerlink Cable is fine

2. Source is fine - AUX input from BS4000

 

Hi

Does the hummm stop after a while?

Best Regards

 

David

Maybe a transformer problem?

Location: San Francisco

I'm an automotive audio and acoustic engineer. I design loudspeakers and full sound systems for new automobiles. I also dabble with studio, consumer and pro audio projects from time to time.

Could definately sound like a problem in the power supply.

The humm is constant - more audible with no audio signal and power on.

I guess while playing music the hummmm is supressed. Is it a simple fix to replace the power unit - the transformer i guess

If the humm is constant please try the following:

- Test the same configuration with all lights and other electric things switched off (Most humm's start from dimmed lights)

- Change the power cord to another outlet (the same as your music system or the bl4000 without the humm)

- Physically exchange the two bl4000 but keep all the existing cables (just to be shure you really have a problem in one of your beolabs)

Good luck

David

  

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