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
It won't do anything about the noise the line picked up from the power station to the outlet you plug it into

Yup.  Which is why money is better spent on an isolation unit like the Tripp Lite IS500 I use for my audio system.  Nothing like a big fat toroidal transformer to clean up the noise in your input power. 
Power Cords are awesome but i dont thimk you will benefit because the Marantz is too to allow you hear a difference 
Your system deserves a proper preamp. You can get one with home theater bypass and still use your marantz for cinema. 
I used to have the av8802 and the multi channel McIntosh, getting a proper preamp was a game changer. 
People that claim to hear a "difference/improvement" with a different power cord are deluded. The sound of an electronic component starts with what comes out of the power supply. Not with anything before it!
Would your car have improved gas mileage if you used a custom hose to fill up the gas tank? Same thing applies to power cords, wall outlets, power conditioners. 
"...the quality of the power cord matters just as much as the quality of the power amp." - this from mc who is an anti-science proponent of useless/waste of money tweaks.