The Clapton video was recorded on a Direct TV box via a dish on the roof (hard drive I’m guessing), so there was no "air" transmission involved in the playback process.I am pretty convinced by my experiments that the S. G. like i already said here work THROUGH the electrical grid of the connected appliance or gear...
All electrical gear in a house partake to a common noise floor of their own...
I am not a scientist at all.... Just my own opinion....
But my ionizers work the " air" with results on par with my S.G. grid... i rarely mention that here because of all the "enlightened minds" ready to kill with words.... 😊😁😎😊