What improvements did you hear in going from entry level to high end Audio?


I heard more detail. Better transparency and detail 
calvinj
To m e it all depends on "whose" high end audio you're referring to.  Not all "high end" audio manufacturers float my boat.  But when I do hear differences they usually begin with tone, especially the piano.  Once that is right to my ears, other things fall into place.  Soundstage, dimension, separation of vocals, instruments, detail, macro to micro to macro passages, bass detail and definition, more floating of the sound, decay of notes, large scale orchestration layers with dimension, etc.

Happy Listening.
I must admit some of the high end stuff is not that good that’s why you have to do your research. I don’t buy high end unless I can hear and know it’s probably going to match. I don’t buy sight unseen or unheard. 
Learning how to listen, comparing what I'm hearing to my perceived idea of realism, and finally does the music on a better system take me to a place of emotional catharsis, or is something distracting me from all of that? I used to listen to Love over Gold on an old pair of Kan 2s for hours, it was like a mini vacation for me. Current Tukans are close. Trial pair of Uber hyped A2.4s distracted me from the music, hollow dips, didn't engage me. Music is my drug these days.
Noromance; I really like your definitions and your journey course. That defines for me the essence of the music. I just had a 4 hour listening session with my wife and our favorite red wine. We marvel at all the nuances of our private concerts in our home listening environment. Beginner or advanced, it's all a measure of the enjoyment you pull from the music. It truly is a journey which may or may not have an end in sight.