What is an excellent power cable?

Triode Wire Labs
are the most musical
and most affordable
using them on my Pass 60.8’s opened them up
and lowered the noise floor.

If I may be so bold, I would like to throw my hat in to the ring...
https://nrgcustomcables.wixsite.com/nrgcustomcables/power-cables
https://nrgcustomcables.wixsite.com/nrgcustomcables/testimonials

Although it looks more like a power conditioner than just a power cable, it's hard to fault the sound of a Core Power Tech 150, which Mark at CP sells occasionally for under $400, closer to $350.  I use one on the TRL DUDE preamp, and another to take power from my Synergistic Research QLS-6 strip to the Maestro outlet.  Each made a significant difference in the overall sound to more live and real. with detailed & organic sound.  To be honest, I haven't heard any of the really high cost PCs over $1000, but do have a Dynamic Design Spirit II that was $900 when I bought a demo from DD for $475 that powers my Modwright 5400 CD/SACD..  The CPT cords are much more real and involving sounding than it also.  I still like it enough to keep using it in my system.  It gets the benefit of the CPT-150 as all my front end components are run through the QLS-6 into the CPT-150.

Bob

The New Pangea mk2 , and mk2 dig
Use now only Cardas best Copper  and it is a warmer sound in msny
System a a plus. Especially under $300.

Sure you can do better if you have several times the $$ to spend.
I have one on my DVD player. I use the New Verastarr power cords 
And system cables totally  reference wuality cables.

I’ll second the Signal Cable recommendation Mofimadness provided above. Based on recommendations by him (thanks, Mofi!) as well as numerous others in past threads here I chose Signal Cable power cords for my CD player (a Bryston BCD-1) and for my power amp (a VAC Renaissance 70/70 MkIII, which is a tube-based design biased in class A), and I’ve been very pleased with the results.

I’m using Signal Cable’s Magic Power Digital Reference cords for the amp as well as for the CD player, by the way, even though that cord is nominally intended for use in digital applications. The 12 gauge wire it utilizes, while narrower than the 10 gauge of the less expensive non-digital Magic Power cord, is more than adequate to power this amp. And I chose the Digital Reference cord particularly because of the excellent double shielding it is said to provide, since in my setup these cords are routed such that they pass fairly close to my phono stage, which I didn’t want to be exposed to amplifier-generated noise. Also, the fact that the amplifier operates in class A (rather than class AB or class D), and therefore draws essentially constant current regardless of the dynamics of the music, presumably lessens the relevance of the advantage some other more expensive cords **might** have in their responsiveness to abrupt changes in demands for current, i.e., in their bandwidth.

In general, shielding quality tends to be particularly important in the case of power cords for digital components and power amplifiers, both of which can couple RF noise into their power cords, from where it can find its way into other cables or components in the system.

There are just so many. It seems daunting.

Hopefully the kinds of considerations I described can help you narrow down the possibilities a bit.

Regards,
-- Al