Except you can make up for a lot of the preference stuff with an equalizer(and no, equalizing does not reduce quality in any way), no need to buy audio gear that limits you to one kind of music when you can get audio gear that measures well and then equalize until you get your preferred sound.
Again, saying equalizing doesn't reduce quality is opinion, one that much of European and Japanese hi fi disagreed with for years (American hi fi almost always loved them). Many preamps don't even have tone or balance controls for this reason, just a passive volume pot and source selector. Me, I have no opinion on them, as really every album produced goes through basically a high end version of an equaliser anyway, with settings set at a producers whim or what market trends dictate that week. You could argue that a computer program can reproduce Monet's art as well as Monet, it may even be true, but without the original to hand, you are still believing what you are being given translated, or what you prefer. I would say again that if the equaliser is the cheapest option to get what you want, use it. If you try a new CD player and prefer the sound, its quite possible that the equaliser can emulate it, but its also possible it won't. What works for you, works for you.
I like this NwAvGuy, he talks much sense, Although he places a lot of weight on people trying to please the tester or get the opinions 'right'. If you scrap that and just say what you personally prefer, with wine or hi fi, its as good as a review as anyone can give. If you prefer the $2 wine to the $200 wine, god damn sure you say you prefer it. He also speaks of things making changes but not necessarily more $$$ = better. Which is pretty much it.
As far as cables go, I can say that with my hi fi, in my room, with the people I had listening to my stuff, they could pretty much all notice changes between cables. But I will say that different albums, any different component could kill that dead. I am very likely to say if I tried 2 of my cables on another's hi fi, I wouldn't hear the difference, let alone them. For all I know all my components are lousy and produce imperfections that the cables actually managed to tune out, or they just resonated right with the albums I played. But sticking an electrical meter on the end of cables doesn't tell even a fraction of the story. If one setup playing one album, changing a cable can change the sound, then I believe an ABX blind test would pick it up. Whether its the $7000 cable or the $2, who knows. If its the $2 ones, im gonna use them. if its the $7500, im still probably gonna use the $2 ones. If the better sounding ones are $20 I will go for it. Which is what I did. Honesty with yourself while testing is quite hard for people, apparently, but it is the only way to truly find something that you truly prefer. The longer the test, the better.
When CD players came out, it was determined by many many tests that 16 bits of data storage would allow for the smallest sound changes any human could pick up. Then pioneer created a system to increase the data to 17 or 18 bits, and for the extra bits they 'randomised' what those bits would be. The result is that people felt it sounded warmer, less glassy, less artificial. Not universally, but enough to sell a lot of Legato Link CD players. Perhaps what oscilloscopes and meters discerned people couldn't distinguish didn't agree with what the ear and body could distinguish. Go compare a couple and see maybe
Incidentally, on one A/B test, things in the rooms on shelves actually vibrated with one and not the other. Who needs ears when the furniture can spot the difference?
but no, that wasn't a cable change.