I used to make a living as a mastering engineer, where the job description is to make many tiny changes near or even beyond the threshold of perception, which when summed may add up to a perceptible whole.

How to do this? It's simple: isolate and magnify. Zoom in to where your senses become reliable, make a change informed by your knowledge and experience which you predict will be beneficial, then zoom out. You don't need "golden ears" to be effective: you need an understanding of your tools and techniques and an appreciation for how they affect the gestalt.

The human perceptual mechanism is prone to illusion, and unreliable for measuring and comparing fine detail — that's not what it's for. You won't go wrong if you think of it as primarily designed by evolution to model and identify threats: to hear a twig snap while ignoring the wind blowing, to perceive that hint of unusual movement by something vaguely alligator-shaped in your peripheral vision while ignoring the waves.

Enjoy wine, or that Stradivarius recording, accepting that you might be fooling yourself. Even if you might be wrong about the wine or the Strad, you know for absolute certain whether it is making you happy! Leave it to the critics to claim perceptual accuracy they don't possess and to risk being exposed.