Power Cable DIY - Please advise

Through the years, I have read all the posts concerning expensive power cords and such. We all want better sound, but I can't get my head around how an expensive power cord in series with house romex wiring and power amps and such can possibly improve the sound.  Good quality receptacles and plugs, as well as the proper gauge of wire IS important, but putting a short piece of expensive wire in series between your power source and your equipment and expecting an improvement in the quality of sound, is lost on me. 

I would consider these fore mentioned improvements in sound associated with psychoacoustics.  If you think you hear an improvement in the sound, that's all that matters.  I remember back in the seventies, probably before a lot of you were even born, people were talking about how placing concrete blocks on top of power amps and pocket change on top of speakers, in a certain order, improved their sound.  I think some, if not all of these were in jest, but hey-if you can hear the difference, go for it.  I think the single most important, but least considered improvement most people can make in their sound,  is room acoustics.  We all have our opinions.  Some are worth exactly what they cost you to read them.  I usually don't chime in, but do enjoy reading and considering everyone's opinion.  
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