It's a precis of the full opera condensed on to two sides of an LP. It contains all the major elements of the music; a brilliant piece of editorial work, both frightening and very moving. As a 16-year-old I was very affected by the grandiosity of it all.
Other important pieces of music to me are Miles Davis/ Gil Evans's Porgy and Bess, which is another way of doing opera in a populist style, with artistry. Bob Marley's "No Woman No Cry": great song. Led Zeppelin's "Four Sticks" I like partly because I was there in the studio - saw Bonzo come in with two drumsticks in each hand, which suddenly explained everything. And Stephen Stills's "Black Queen", which is just brilliant improvisation by a man out of his head on Tequila.