I have 2 44BXs which were both rebuilt and blessed by Charlie Gand before he passed away. They've both functioned well for years. In my new studio I seem to be in a substantial 60Hz EMF field (I think from the high voltage running down the street outside). Both the RCAs hum (which I can null out somewhat with position) but one is much louder than the other. Their output seems to be fairly well matched. I can't see any physical difference in terms of shielding between them.

The AEA clone I’ve used seems to be about the same as the better of the two vintage 44s. I don’t have this problem with my Coles or Royers.

2 Questions:Is there any way to better shield the 44s? Any Ideas why one would be more sensitive to 60Hz?

Thanks in advance.