As a HiFi hobbyist, I would like to defend the HiFI concept. We all know HiFi doesn't sound the best, but HiFi grants little to no unintended distortion and noise, which gives a clean system for the user or DSP engineer to add intentional distortion and flavor.
In other words, if my system is almost ideal, by doing some DSP trick, I can clone the sound characteristics of any existing, lower performance systems. This allows me to quickly adapt to customers' preference and competitors' latest product.
HiFi or even audiophile equipment is not the same as audiophool voodoo.
I have tried expensive loudspeakers (Kef, Tannoy, B&W and ProAc models at around $5000 euro a pair) and the sound was really awesome. That said, no system is perfect. I remember a pair of Epos loudspeakers I tried once. The voices from a recording of Bach's Matthaus Passion were incredible, like the singers were in front of me. But the orchestra was a bit mushy, like behind a thick curtain. More expensive than that? Probably it's like comparing a Rolex to a Seiko.
With amplifiers I think that the main difference is how they distort. I remember, when I read some HiFi magazines now and then, some esoteric amplifiers that got the highest scores in the listening tests were the ones with more distortion and RF interference susceptibility. Which wasn't surprising to me of course!
Anyway it comes down to what you like. Some people like loudspeakers with boomy, exagerated bass around 100 - 200 Hz. Other people, especially with age, like a small oomph on high frequencies. What's wrong with that? Moreover, unless I am wrong loudspeakers can play interesting tricks with amplifiers because of their impedance curve. Some "8 ohm" speakers can have as little as 2 ohms at certain frequencies and that can induce some distortion depending on the frequency content falling into those "hotspots". So often the "hey, this amplifier sounds great with these speakers" can very well mean that you hit a hotspot you particularly enjoy.
The only way to judge how authentic your equipment sounds is to go to the studio where the recordings have been mixed and compare the sound. The carefully calibrated monitors in a well designed room will be the real reference.
When I go shopping for HiFi gear I take 10 CDs that I know well with me, two recorded by myself even, and I judge wether I enjoy the sound or some weakness gets especially obvious. That's it.
And what do I have at home? Well, nothing especially fancy. A 25 year old combination of a Nad 302 amplifier and Tannoy 632 loudspeakers. I know its shortcomings of course. I have a very expensive audio interface for recording (Metric Halo ULN-2) but the reason is simple, it has awesome microphone preamplifiers with a very high S/N ratio and a lot of gain if needed. As I said it's so good, some people find it "boring", "cold" and "surgical" and resort to the equipment emulation (ie, adding very mild and gentle distortion) to give it some "spark"