Lawrence Dillon’s official Sequenza 21 list of 111 influential post-1970 musical works is worth taking a look at, as representing a diversity of tastes (including mine, and I appreciate his including it though I’m not a Sequenza 21 contributor). As he notes, there are a lot of celebrated composers that no one claimed as a compositional influence. Henry Cowell, I think it was, used to say there were “two kinds of music in America: the kind people talk about and don’t play, and the kind people play and don’t talk about.” Played or not, here’s a list of 111 new pieces people talk about (numerologically auspicious, since both Beethoven’s and Brahms’s Op. 111’s are important pieces for me).
While we’re at it, and since I’ve mentioned Duckworth recently, at the end of the 20th century (how well I remember it) (not really), Bill Duckworth wrote a book called 20/20: 20 New Sounds of the 20th Century. Similarly to Dillon, he queried all his musical friends and came up with 20 works that seemed to be the century’s most important, using the criterion, “Which works matter most to you personally?” Here’s the list he came up with:
Debussy: Prelude to the Afternoon of a Faun
Joplin: Maple Leaf Rag
Stravinsky: Le Sacre du Printemps
Schoenberg: Pierrot Lunaire
Ives: Concord Sonata
Gershwin: Rhapsody in Blue
Ravel: Bolero (personally? Well, OK)
Messiaen: Quartet for the End of Time
Copland: Appalachian Spring
Cage: Sonatas and Interludes
Hovhaness: Mysterious Mountain
Riley: In C
Reich: Drumming
Lucier: I Am Sitting in a Room
Johnston: String Quartet No. 4, “Amazing Grace”
Glass: Einstein on the Beach
Ashley: Perfect Lives
L. Anderson: O Superman
Pärt: Miserere
M. Monk: Atlas
He also includes the 86-piece “long list” from which he culled the 20, but you’ll have to buy the book to read that. I can’t do everything for you.