Have you been surprised by power cable changes? s

+1 millercarbon

The power cord only comes into play on amplifiers if of insufficient gauge for the current draw. Without power conditioning, power cords can bring noise from switch-mode power supplies into the audio chain if filtering on each component is inadequate. 

I too was late to the power cable game.  A few months ago, I splurged on some Mark Tunis Stealth power cables and the difference is absolutely stunning.   It is not subtle.   Much more bass, tight, well defined, and dynamic too.   Much airier miss and highs.   The black part of the music is now black.   What a difference.

i remember laughing at Enid Lumly’s articles in the Absolute Sound in the early 80’s when she went on about how power generation statins sounded differently one to another, but now I think she was on to something.   It was the cables.   I humbly apologize to her now.

+1 millercaron too.

Hi, I have recently upgraded my systems and cables. System is in region of usd 30k. Through the journey, i can affirm that cables, power cables, interconnects, speaker cables, digital cables, n even fuses all audible differences. The extend of difference they make also depends very much  on the quality of yr system n the items one buys. 
Cables can range fm tens of dollars to thousands of dollars. 
As budget is finite for many people, in my personal view, its important to make the max out of it by spending first on amp, speaker, cd player /streamers first. Then get the cables that makes proportional sense to yr overall spent. 
I hv been rather happy upgrading cables recently, costing thousands. But its money well spent for the SQ upgrade. 
There are many brands in the mkt, so it can be very daunting trying to find out which brand, systems, cables gives you max value. And remember the law of diminishing returns too. 
To certain extend, the audiogon forum helped me in my journey of audio upgrades. Thks to audiogon. :)