Magda Olivero, an Italian soprano who for decades whipped audiences around the world into a frenzy of adulation that was operatic even by operatic standards — despite the fact that by her own ready admission she did not possess an especially lovely voice — died on Monday in Milan. She was 104.

Her death was confirmed by Stefan Zucker, president of the Bel Canto Society, an organization devoted to the history of opera singing.

Miss Olivero began her career in Italy in the 1930s and had largely retired by 1941. Coaxed back to the stage 10 years later, she enjoyed renewed stardom in Europe and the United States.

Her long second act — she made her Metropolitan Opera debut at 65 and continued to sing elsewhere for decades — was driven in no small part by the ardor of her fans. “Magdamaniacs,” The New York Times called them in 1979, and the coinage entailed little hyperbole.