@uberwaltz,
I think I misread your inquiry.
I'm a fan of passive AC conditioners. There are many popular products out there and are well regarded that use transformers. Products like the Niagra..... have you looked inside of one? All of the circuit boards/transformers.... then read user's comments regarding the noise they put up with after spending thousands. No way bro.
I've had several products in house that use earth minerals, man made crystals that absorb EMI/RFI that work very well with nothing to cause noise or break down.
This is where my $ will go.