Jacques Isnardon (15 February 1860 – 14 November 1930) was a French bass-baritone, writer and voice teacher.
After winning a competition at the Paris Conservatory, he made his debut as Baxter in Émile Paladilhe’s Diane at the Opéra-Comique in 1885, before moving to Brussels and the Théâtre Royal de la Monnaie, whose history he chronicled. He sang in Die Meistersinger at Covent Garden, Manon at La Scala and Le médecin malgré lui at Monte Carlo before returning to the Opéra-Comique in 1894. His Le Chant Théâtral is as much a memoir of his times as a philosophy of vocal pedagogy: “Herein is but one method: the new method for each pupil”.
He sang in the world premieres of Jocelyn and Le chevalier d’Harmental; other roles included Mozart’s Bartolo and Rossini’s Basilio; Puccini’s Colline and Leoncavallo’s Schaunard; Masetto, Lescaut, Enrico & at various times 5 roles (Mercutio, Paris, Gregorio, Laurent and the Duke) from Roméo et Juliette.