... abit confused: how does a power cord affect the presentation of sound...

Hello to all...

I was shifting around components in my system, trying to squeeze out better controlled bass, more definition within the soundstage, and better define the "voice/midrange" presentation...

I presently have a tube preamp (hardwired with a wall wart) into an HT Receiver; source is a Marantz SA-8001 CD Player

Swapped out a Yamaha HTR -5550 (hardwired) for a Parasound HCA-750A (which needs a power cord).

CD Player is powered with a PS Audio Statement SC power cord, so I went in my closet and pulled out another PS AUDIO Statement SC power cord, hooked it up and expect to give it at least 5 days continuous re-break-in before serious listening.

Took a minute to lookup reviews about this power cord - and I read some rather confusing reviews: some luved 'um, some liked 'um, but some thought them " ...slow... " (?), and giving a veiled presentation...

I'm gonna listen and decide myself - but I'm abit confused: how does a power cord affect the presentation of sound - I know that interconnects and speaker cables would/could/Do affect sound presentation - but how could a power cord?

Explanation/thoughts please...