[khazhoux]

> What does it mean to understand a piece of work? Do I have to read the sheet music? Do I need to know musical theory? Should I be familiar with the composer's background? The definition is somewhat vague.

Oh no, I didn't mean any of those at all. Quite the opposite.

I mean "understand it" as the opposite of "it sounds like nonsense." It's at the intuitive level, not about the ability to reason the structure details or whatever.

Everyone grows up listening to some particular types of music in their household, culture, etc. You naturally develop an intuitive understanding, in the same way a native speaker has adopted the rhythms and tones and phonemes of their local language. A typical modern American listening to Charlie Parker rip through a bebop solo, is not too different than listening to someone speaking Mandarin. The sounds don't map onto anything recognizable. But you listen to it enough, and the brain starts to understand the structure. It's not just a blurred stream of saxophone, but a series of phrases, with inflections, patterns, meaning. Listen to it long enough, and you hear every individual note as it flies by.

[layer8]

I believe I do understand classical music in the sense you describe, but I just find it mostly boring. Its features are not what excites me in music.