For electronics its anything with errors in reproduction below the threshold of hearing (and with enough power for your use case in case of an amplifier). Transducers is a difference story.LOL. What would you recommend I get to have a high fidelity sound? What DAC, AMP and Headphones do you think will create this high fidelity sound you speak of? Teach me, I am obviously misguided...
And I don't think you are misguided, you just decided to focus the experience and not the sound on its own. And that's ok, its just that most people don't enjoy spending 2x, 5x, 10x, 20x or even more for the same sound quality.