Copper mesh cloth faraday cage!
Do you have router or streamer close by?
My Pi2AES is about 5 feet away. I have a laptop and a Thunderbolt dock on the shelves above the AF, but when I unplug them the RFI/EMF noise only goes lower in volume it doesn't go away. I have lots of charging cables for phone/camera gear etc about 1.5 feet under the amp.
The weird thing is that when I first plugged the amp in, it was quiet all day the first day. Then it developed this sensitivity. I think I just need a new pair of these 2a3 tubes.
A made it a bit prettier with just one layer for better heat dissipation. And it works just as well.
Next step is to wrap my head in this cloth. :D
What brand 2A3s are you using?
Did you experiment if it is maybe the input tube picking up noise instead?
They are RCA 2a3 tubes. Im sure it's the 2a3's because when I swapped the from right to left the noise followed the tubes from the right channel to the left channel.
This is why we need fiber networking :P
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