My perspective on this topic has somewhat changed over the past few months. I think all of us have recordings that we consider to be stellar, others that we consider to be poor, and others that that don't warrant a strong opinion either way.
If I want to show friend what a truly poor recording is I pull out a couple of my Josh Groban CDs that I simply cannot listen to anymore. Ironically, one of them was actually one of my test CDs that I used when making my first "audiophile" type of purchase. I know cringe at the pain that I must have caused the salesman that sat on the couch and listened with me.
In any case, I have a several other CDs that I very much enjoyed with my original gear which was an Integra receiver that I still have along with my current Focal speakers. They were some of my go to recording for enjoyment. Every time I made upgrades to my system these recordings always seemed to become a little less enjoyable. I figured that it was just that they were poor recordings any my system was becoming resolving enough to expose them.
Then with my most recent upgrades that include rolling tubes, upgraded power cables, and upgraded interconnects my system really went to the next level. What surprised me is that the recordings that seemed to always suffer from upgrades became wonderful to listen to again and are now back to being some of my favorites. My Josh Groban recordings still sound like junk.
I think my Integra receiver has the edge when it comes to making poor recordings sound good because it has the digital processing capability that really seems to benefit poor recordings.
To summarize, I have had several recordings sound worse and worse as I upgraded and then unexpectedly the magic returned.
I think we all have recordings that we use for testing purposes and I'm thinking that these particular records might be an indicator of system synergy.