Turntable Power Cord Upgrade

I put a $500.00 Shunyata power cord on my VPI Prime turntable and heard no difference.  I have that same cord on my Technics SL1200G turntable and still don’t hear a difference although it does look nice.  I talked to Matt Weisfield @VPI about an aftermarket cord for the Prime and he laughed and told me the motor won’t know the difference.  He was right. 

The sound of a component starts with the power supply - not what comes before it! Physics 101! 

False. 
Only if the power supply is perfect. 
No power supply is perfect.
Whatever noise or fluctuations are on the incoming AC, some of that will always make it through the imperfect power supply. 
Because: no power supply is perfect.
Therefore, the quality of the incoming AC does matter.

Logic 101.

I should have pointed out that the Kuzma motor is dc, that being the case I would assume that any difference would be minor. I am using a Cardas Beyond Clear right now and will try others I have on hand to listen for changes. Just wanted to pick some brains, thanks.

The same applies AC or DC. The main exception being if the DC involves a battery, and if the AC charging the battery is disconnected during play. Because essentially, as I just showed, as long as there is any connection to AC then some of the noise on the AC line is going to get to the DC. The one exception is when a battery is used, and even then only when the battery charger is disconnected from the line during play.  

This isn't guesswork or rumor. This is actual experience running all these different ways.