When does the law diminishing returns kick in?

I can't spell his name but the guy from the tv show wherein he says "D-plane/D-plane" was considering suing his local city for building the sidewalk to close to his ass.

Audiophilia is made up of many types of individuals with varying priorities. Realistic playback of recorded music at home is not the end-all of involvment in this hobby.

Some are 'gear hounds' who may never really be happy with their system, no matter what it sounds like. Others are content with just enough gear to create pleasant noises in their environment.

Unfortunately, there is no linear standard for diminishing returns. It depends upon any number of variables. There are incremental improvements or degradations in most changes to a system, including those that don't cost money (cleaning contacts, repositioning speakers, other DIY tweeks.)

My best advice is to take a weekend trip to the big city and listen to as many pieces of gear as you can. How better to know if spending more will increase your enjoyment than by listening?

The law kicks in when you find yourself taking out a second on your house to finance that new cable upgrade.
Enjoy what you have! Depending on the type of music you listen to, it may not matter if your speakers or cd player can't go down to the lowest octave. Or if your hearing cuts out at 12Khz why pay for that new ribbon tweeter add-on?

The law of deminishing returns usually sets in after you have bought a prospectively wonderful component and find that it sounds like crap in your system!

I'll share a few observations from recent experience. There is a point of diminishing returns; it is subjective, and of course it does vary with pocketbook. For me, I hit that wall when I realized I'd spent too much buying equipment, amp and speakers, too big for my room. I had way more wattage, bass extension etc. than I really wanted for the way I actually enjoy music, as opposed to the way I might show off new gear.

To get that gear to open up all the music, it was uncomfortably loud; I felt beat-up by the pressure wave.

After downsizing, I had a system that cost far less and brought me more musical pleasure in the near-field at moderate volume. For me that came down to some of those 'why spend more?' components; mini-monitors around $1600 USd, and a tasty integrated at about $1200.