When I was taking Chinese, my professor would say that tone-deaf people couldn't function in China because you need to to be able to reproduce relative pitch in order to speak the language. Chinese is a tonal language, so you would think that they should always have perfect pitch. However, this video of a
Chinese singer shows that being unable to carry a tune is a universal problem.
There's actually a whole range of abilities between "tone deaf" and "perfect pitch". Perfect pitch means you can hear a note and basically say "oh yeah, that's F#". I hate and envy those people. Tone deaf means you can't even deal with relative pitch differences. Most people are neither. I *wish* I had perfect pitch, but actually, I have a probably slightly worse than average ear for relative pitch... I can still tell the difference between tones in Thai.
My mom has even worse pitch than me and she's a native speaker. :)
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