Is it OK to recommend fiction? On holiday, I read Richard Powers' Orfeo:
which is a novel slightly about biohacking, but really about a history of 20th century composition seen through the eyes of a single musician, who is at college in the US in the 60s - ends up seeing Cage's Musicircus in 1967 - and is constantly trying to work out where he fits into music.
I found it wonderful - perhaps it's overwritten, perhaps it's a tad clinical - but it overflows in places.
Music, he’ll tell anyone who asks over the next fifty years, doesn’t mean things. It is things. And for all those years, in fifty-four pieces from fragments for solo flute and tape to full orchestra and five-part chorus, his music will circle around the same vivid gesture: a forward, stumbling surge that wavers, sometimes in a single measure, between the key of hope and the atonal slash of nothingness.
Also: the orchestration of Els' pieces always feels like a lovely running joke; he has an idea, and it's about to be a thing... and then he orchestrates it for whatever combination fits the era he's in.
Also, a long sequence about the history - and origins - of Messaien's Quartet Pour La Fin Du Temps nearly made me cry. Tears are an easy emotion, and not necessarily a sign of greatness, but god, that section alone is worth the price of admission.