My take on this is that when you have really good interconnects and these fantastic Decware components you can hear the changes that a power cord, and power treatment, and isolation make. Some are subtle, some are more than that. I've had a power cable make a really good impact on a component more than once. Most recently I got an Apple TV so that my wife can watch new HGTV shows. (Oh joy.) I have an excellent HDMI cable connecting it to other excellent HDMI cables that split the sound to the Universal Player and the TV. I liked the sound but decided to play around with the power cord feeding it and so I tried an Audioquest cord with a C7 connection. A slight improvement. Then I realized I had one cable that gave a warm and solid sound, an Anylisis Plus Oval Ten, and an IEC to C7 adaptor and hooked those up. BOOM. Using the DAC within the Universal Player and then to the Decware ZBIT, ZROCK2, pre and amp the sound improved considerably. The picture quality imroved a mite, but the sound was surprisingly transformed.
I've decided after a few decades of personal research
Everything matters when you have these Decware components as the heartbeat of your system.