The field of AC power conditioning for audio systems has undergone a radical transformation since the first AC conditioners appeared about 20 years ago. Those early products were developed largely through trial and error, and often did as much harm as good. (Does anyone remember the Tice Power Block?) AC conditioner design was a “black art,” with the designers of the day not fully understanding the phenomena by which AC power affected sound quality.
~ Robert Harley, Reviewer at The Absolute Sound