New expensive power cord for amp and no change in sound?

I bought new an expensive(for me) well known and reviewed power cord for my very good amp and plugged it directly onto the wall socket. After a couple of weeks of daily use I hear no change in the sound quality from a $500 cord. I don’t want to name it for fear of getting my thread deleted. You would know it or at least be aware of the company. Did I throw away several thousand dollars? Before I get the snake oil answer I want to let you know that I bought an upgraded cord for my pre as suggested by the pre’s manufacturer and am pleased with the results.

I guess for full disclosure the amp’s manufacturer said don’t bother. But I had had good luck with the pre so I thought it would be a good idea.

Anybody else have this happen to them?

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It could be that the $500 cable you mention may not be the best premium PC in its price class for YOUR system

@waytoomuchstuff  , OP has stated that he upgraded FROM a $500 power cord to a power cord that cost "several thousand."

OP should have listened to the Pass Labs engineers.

Yes my amp is a stereo Pass 250.8 and the manufacturer said don’t bother. I originally had a $500 going into the Pass and replaced it with the expensive cord

Nope!!!!  Never happened to me.  Over the years, every single time I've changed or upgraded a power cable, whether it be for an amp or any other component, I always heard some kind of change in their sound.  Sometime the change in sound was subtle, and sometime it was more pronounced.