Delmas was born in Lyon and studied at the Paris Conservatoire winning first prizes for operatic singing.
He was known for the power and evenness of his voice with a sonorous quality in the bass range and an extended upper register, which allowed him to sing classic baritone roles such as Iago.
[1] His recordings for G&T, Pathé, Zonophone, Fonotipia, Odéon, and Opéra-Saphir are highly sought after by collectors.
[1] He also created roles in Le Mage (Amrou), Messidor (Mathias), L'etranger (l'Etranger), Ariane (Périthoüs), Monna Vanna (Marco Colonna), Roma (Fabius), and sang in the Paris premiere of Fervaal (Arfagard).
Delmas died in Saint-Alban-de-Montbel (near Chambéry) at the age of 72, and is buried in the Cimetière Saint-Vincent de Montmartre with his wife, the soprano Blanche d'Ervilly (1853–1920).