@arizonabob I too have pondered this very thing from time to time. I feel like you get to a certain price point (not entirely sure what the number is though I guess it's different for everyone depending on what you can afford) where to get the slightest bit more detail (for lack of a better word) from your system, you literally have to pay double what you have already spent. The question then becomes are you willing to go there. Using speakers for example, I currently have Dynaudio Evoke 50's. To get to the next level I'd have to move up to Contour 60i which are literally double the price of Evoke 50's. How much better can it get, double thereby equaling the cost? For me no way. Not possible. Are the 60's better, have more detail, soundstage, etc? I am quite sure even though I have never heard them, but I can't afford them so I don't even think about going there. Regardless I'm happy as a clam with my Evoke 50's. But I totally get your post as I too have had that same thoughts...
Anyone (everyone) care to throw a dart?
I understand my hearing at 69 isn't even close to what it was at 19. I'm sure your results may vary. However, anyone care to throw a dart at the price point where diminishing return kicks in? There must be one out there. Regards, AB