Where does "MidFi" differ from "HiFi" or "LOFI"?

@cd318 indeed. This Fletcher-Munson curve has been discussed on here several times. Hence the need (if we are honest) for either an EQ or what used to be termed a "Loudness Button" that would compensate for how the human ear perceives the frequencies below and above that critical 3KHz-4KHz range. 

We all know there are budget components, midrange components, high end components, and cost is nearly no object components and manufacturers try to hit those ranges depending on what market they think they are serving. 

But there is much overlap between many of these devices, and of course a diminishing return as you go up the food chain from midrange to high end. 

If you can get good sound quality with a system costing $15K and you have to spend $30K or more to hear a slight difference in sound, it is up to the individual how much it is worth to them to get that last 5% and whether or not it will ulitmately make them enjoy listening to music more.  That's just it. As noted by others, there are two extremes of audiophiles: Ones who appreciate listening to the music and what the artist is conveying sonically that causes an emotional response, and the others who are listening to their equipment and how it is performing, with most falling somewhere between those extremes.  

It's like DACs. It seems we have those who are just fine and happy with good quality chip-based sigma-delta DACs and those who think anyone calling themselves an audiophile HAS to have an old school architecture R2R DAC. Well, maybe.

I have a totally different take on this.  Breaking down these categories by price point is basically another kind of objectivist approach.  The High End or whatever you want to call it differentiated itself originally by its focus on sound quality and I'm sticking with that.

High Fi - companies that place primary value on how their equipment sounds

Mid Fi - companies that focus on marketing features, cosmetics, prestige

Low Fi - PA gear, generic soundbars & portable speakers

I'd say pretty much everybody on this forum is philosophically High Fi; just being here is sort of self-selecting.  Note this definition allows you to spend over a million or under a thousand, believe solely in measurements or listening or just reading the brochures to choose.  We all have this one thing more in common with each other than with the vast majority of people, who are happily Mid or Low Fi

it differs in the ears of the beholder ... 

As others have noted, ignorance is bliss, but once you've heard the good stuff it can't be unheard, so now the bliss is gone. And yet: 4 of every 5 remain perfectly satisfied telling their "smart speakers" to play X. The fifth one becomes the audioholic.
Same thing happens in relation to wine. You give them their first taste of the good stuff -- well-aged grand cru Burgundy, single-vineyard ancient vine Albariño, etc., -- and they can tell it's special, yet they remain perfectly happy with same-day, grocery-store plonk for the rest of their lives. Only one in five is smitten. So it's not torture for all. Those posting here are the ones who got the bug. 

Interesting thread. I’d like to see what brands everyone thinks should go into each category.