RFI from steel TV bracket?

What *other* changes did you do?

No other changes :^)

When I unplug the output from the pre-amp......the hum is still coming from the speaker.
But when I unplug the input to the amp (with the output still connected to the preamp)......the hum disappears :^)
If you're right.......any solutions other than removing the steel wall bracket?
Thanks
Henry

Yes I unplugged the TV and also tried it in different GPOs.....even a power conditioner. I even disconnected the 'sound-out' of the TV from the preamp. Hum still there.
Interesting thing is that the hum is from the amps and not the preamp as when I listen to my headphones which are plugged into the 'tape-out' of the preamp......no hum?

Last TV was plasma. No hum.
This TV is LCD......hum.
But it hums with the TV completely unplugged so I don't see how it can be the source?

I unhooked the cables from the cable TV......no change.
I then suspected the 2 metre long Cardas cable interconnects running on the shelf behind the TV and just under the steel brackets and plate.
The right-hand interconnect runs right across this 'field' before dropping down to connect with the speaker....whilst the left channel interconnect runs for only a foot before dropping down.
The left speaker only emits a light buzzing whilst the right speaker has the definite 'hum'.
So I wrapped both interconnects in aluminium foil and this reduced the level of the hum and buzz.

Not knowing much about electricity.......is it possible for the steel bracket combining with all the power outlets directly below it, to create an electro-magnetic field which the long runs of unshielded interconnects then acts as 'antennae' for the RFI/EMI?

If this is indeed the problem.......would going to fully balanced XLR interconnects, solve it?

Hi Ralph,
The interconnects were running under the steel bracket.......not draped over it.
The speaker leads are on the floor well away from the bracket (as they have always been).
I just re-routed the right channel interconnect to along the floor away from the steel bracket........but the hum is still there?
Again.......if I run in fully balanced configuration from preamp to amp......shouldn't this prevent any RFI/EMI interference?
Isn't that why all professional sound systems run in this way?

I still think there is a possibility that the interconnects that go from the preamp to the amp my not be shielded enough for the new environment.

That was my initial thought which is why I wrapped them in aluminium foil which reduced the hum somewhat.
I hope we're all right as I've just ordered an XLR pair of Cardas Clear interconnects and George Cardas tells me they are the best shielded cables he knows of?
He guarantees my satisfaction.......which is a great attitude from a manufacturer.
I'll know in about 3-4 weeks when I receive them. Fingers crossed :^)
Thanks for all your help.
Cheers
Henry

Received the Cardas Clear XLR interconnects today and installed them between the Halcro DM10 pre and the DM58 monoblocks.
Absolutely no hum or buzz whatsoever.
The shielding in these cables is obviously so superior to the old Hexlink 5 interconnects and/or the balanced XLR method of connection combine to lower the noise floor from the speakers to nil :^)
Now I need time to see if I can 'hear' other benefits?