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

I switched out my upgraded PC from stock that were Shunyata King Cobra  (2) last summer for the Audio quest Dragon HC (2) and I’ll tell u I could hear a big difference. More clarity. Bigger soundstage. More details with voices and instruments especially the plucking of guitar strings. Well worth the upgrade. Btw. Amps are ARC Ref 750s. 

Sounds like you’re $500 cord worked great with the Pass. Sorry you had to learn/ relearn that synergy, not price are more important and always listen to cables with a return policy.

@roxy1927

Since you mentioned Shunyata.. I believe that they have power systems which consists of power cables and a conditioner. I really never had much of an expectation of replacing one power cable at a time and noticing a difference, so I took the system approach of purchasing seven power cables and a conditioner with the ability to return everything. In short, I decided to keep the Shunyata products and beg for my next meal. Attention to power has made the biggest improvement to my system, which now runs off a 300ah battery.

There you have it.

"I bought into the never ending advertising but people had positive things to say..."

Also I would up upgraded all my PCs to 4 Audio quest HC and source Dragon PCs and another Audio quest Dragon HC PC for my Audio quest Niagara 5000. All previous PCs were Shunyata high end PCs. Every change that I made from the Shunyata to the AQ Dragons resulted in major sound improvements. Especially the ARC Ref 6SE pre an ARC Ref cd9. But I must also say that I do have a very resolving system. Even when I changed my XLR ICs from Straightwire Crescendos to AQ Thunderbirds XLRs (3) pairs , the difference was a major step up. Snake oil. ??? Hell no.