Nono, who was born 100 years ago and died in 1990, invited listeners to musical extremes, especially that of the dynamic pianississimo, or very, very soft. The score of “Fragmente-Stille, an Diotima” (1979-80), his sole work for string quartet, quotes words from the elusive German Romantic poet Friedrich Hölderlin, to be “sung” inwardly by the players: […]