Power cable education needed


Hi everyone. I need some education on power cables. I have been reading that a good power cable is vital to a good sounding system. If that is true wouldn’t the companies the make the components include a good power cable to insure their product sounds the best that it can ? Should I evaluate the power cables in all of the components in my system? 
ronboco
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I'll give another shout to Shunyata. I have the Delta NR 20 amp for my Simaudo Titan...If your budget is on the lower end try Voodoo Cable Black Magic. I'm actually using this monster (20 amp version) on my Furman Elite 20PFi power conditioner with great results. Under $300 and is built like a tank...Got this from The Cable Co as well...
Shunyata for me.I have a sigma nr an alpha nr, an alpha digital and several deltas. They sure do make a difference and I’ve compared them to ps audio and analysis plus cords that I also have. My theory is that your system is the sum of its parts, so they more weak (parts) links you improve, the better chance it will be able to achieve its full potential. 
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Do I think expensive power cords are better than the cheaper ones? Well it depends, it is like this as an example, and the number is not necessary accurate either. A $500 PC may improve SQ by 2% from the stocked one. A $5,000 PC may improve another 0.2%. Is it worth it? To some it does. But if you cannot hear the first 2%, considered you’re lucky!