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

@curiousjim 

When I bought my briefly-used Classé Audio SS power amps in the late '80s, the previous owner had already outfitted them with Cardas Quadlink power cables (a lower rung in their hierarchy).  At some point I experimented with using some ordinary AC cable, and heard the difference immediately, and went back to using the Cardas.  I don't recall the specifics, but generally Cardas cables seem to result in more robust bass that is easily noticeable if the system can reproduce it.  My system, with a very fine Classé preamp and Apogee Duetta II ribbon speakers, was/is quite revealing.  But I did not hear a difference when recently replacing the power cables on my Bluesound Node streamer or my Denafrips Ares II DAC with low-end Audioquest power cables. 

So, I guess I'm in the camp that says AC cables make more of a difference with power amps than source components, although I'll admit my sample size is small. 

The original owner of my Classé Audio gear, a dealer, was very enthusiastic about Cardas wire--not only did he replace the power cables with Cardas, but he replaced internal wiring on various products with Cardas wire.

@strawj 

What is your system? The effect of power cords is depend on your system. Very helpful to know where you are coming from. You can see my systems under my ID.

The first power cable that noticed a difference in the sound was a Monsrter PowerLine 300. It made everything sound more open, yet detailed and was a real wow from the standard cable.  The same effect was noticed on inexpensive hybrid through All tube McIntosh systems.  Since that time I have used Nordost Blue Heaven and LessLoss. All were different and more revealing.  I felt dollar for dollar the LessLoss was a better performer for anything under $2,500.

pindac,

I just wanted to give you a little update I talked to the person that is distributing acoustic revive and I also read up on triple C, it is no better or worse than OCC single crystal copper all they've done is come at it from a different production angle to produce longer crystals but they do not say anywhere that their crystals are 125 m long like OCC single crystal is so from what I've been reading and researching triple C is not better than OCC single crystal and now Neotech has rectangular OCC single crystal which is even better than the round and Joe who distributes acoustic revive said to me he can see how the rectangular would be even better than the round OCC or the triple C.

Triode Wire Labs was my first power cord to offer an improvement in sound quality