What was the first power cable that you noticed a difference in the sound?

There is one simple answer to this:

If you heard any difference between a standard 12AWG power cable and a $500 Audio-Woo-Woo cable, it was confirmation bias or just delusion. 

It's such fun talking about this stuff with studio engineers. You know, the guys working in multimillion dollar studios, who record and master the music you buy. They laugh endlessly about the absurdity of audiophilia nonsense. But the exotic power cables gets the most laughs. You'll hear phases like "more money than sense" or "crazy deluded muppets".

Virtually everything the audiophilia community is obsessed with defies the laws of physics. Or is of such minuscule consequence that merely moving the speakers a few inches will negate any claimed effect.

If you want to spend some money, get an electrician to run you a nice clean 20amp power supply in Romex 10AWG solid from your fuse box to a set of six hospital grade power outlets. You can get the lot from Home Depot. Top it off with a decent breaker like an Eaton 20amp ACFI/GFCI and the. forget about the whole thing.

The first power cord that made a significant improvement for me is the Shunyata Venom V10 NR.  To my ears, it sounds best on my DAC.  A few years later I purchased a Shunyata Delta  V2 NR. Wow, that was an even greater improvement in clarity and  realism. I also use Shunyata Venom Digital power cords on my iMac and DDC.  Happy listening!

"If you heard any difference between a standard 12AWG power cable and a $500 Audio-Woo-Woo cable, it was confirmation bias or just delusion."

- Well, that clears it up, never heard that point of view before 🙄

+1 dill...I prefer delusion, as confirmation bias, even if correctly used, goes both ways...though I did buy the Woo Hoo not the Woo Woo

Unfortunately never actually, maybe I thought so initially, but I was skeptical of the placebo effect. I’ve owned Nordost, Pangea, Shunyata, Wireworld. I am currently running aftermarket Cullen cables. They are very well-made, reasonably priced, but I’m not sure if they make an actual sonic difference in my system.