Can the average human train their voice to be capable of singing well enough to be ‘decent’? (not pro)

Yes. And moreover more people than not have perfect pitch when singing from memory https://news.ucsc.edu/2024/08/earworms-music-memory-perfect-pitch.html

The Farcaster formerly known as Kchamp. Books, beats, bodybuilding, bright ideas and beautiful things.

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That's really interesting, I've always thought perfect pitch was super rare, guess I was wrong. I'm curious, do people with perfect pitch perceive music differently than those without it?