Troubleshooting AC 50Hz humming in BL3 speakers...

4 replies
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Anniber (archived)
Bronze
Posted January 13, 2010 at 06:58 GMT
#1897298

Please help!

Bought my first B&O system about one year ago, added a pair of BL3 in a link room some months later. Have over time noticed a clear and very annoying humming in the link speakers - clearly AC 50Hz coming through. I have tried everything (except the right thing, obviously): Turned off all possible electronic equipment near the speakers - still humming. Exchanged the ML box - still humming. Had the electrician there to check the Lex Com Home system - slight reduction but still humming. Connected BL3 direct to source - still humming. Swithed positions with my BL4 - still humming in the BL3 (!). Brought the BL3 speakers to my dealer and hooked them up - NO HUMMING. Only thing I have not yet tried is exchanging the power module in the Lex Com Home system.

Does anyone have aclue on what I should try next - I am completely at a loss...😕

Looking back, I should have turned to you guys in the first place - I always knew the true B&O experts reside here!

Thanks in advance,

Anniber

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Puncher (archived)
Bronze
Posted January 13, 2010 at 07:29 GMT
#1897299

What leads are you using to connect your BL3s? I understand correct screening is very important with these speakers.

See

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Anniber (archived)
Bronze
Posted January 13, 2010 at 10:17 GMT
#1897300

Thanks Puncher!  🙂

I will have a look at this when I am closer to my speakers (ie when I get home from work...). The speakers are installed by my B&O dealer, so I was presuming they knew what gear to use. Maybe I will have to review that opinion...  🤔

I will post later when I have checked!

/Anniber

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DoubleU (archived)
Bronze
Posted January 13, 2010 at 16:10 GMT
#1897301

You will get the same humming if beolabs are connected to dimmable switches, even if it is at his highest point. Beolabs need a stable AC outlet.

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