Jaia studied with Raul Frazzi in Florence and Tullio Serafin in Rome.
He made his debut in Gent in 1949.
His repertory included:
I puritani, L'arlesiana, Anna Bolena, La favorita, Faust, La Juive, Il piccolo Marat, Silvano, La bohème, Madama Butterfly, Guglielmo Tell,
Mosè, Semiramide, Un ballo in maschera, Rigoletto, La traviata.
He sang in following cities:
Amsterdam, Barcelona, Berlin, Bologna, Budapest, Firenze, Genève, Gand, Hamburg, Lausanne, Lisbona, London, Lyon, Marseille, Milano,
Munich, Napoli, New York, Nice, Osaka, Palermo, Paris, Parma, Pittsburgh, Roma, Stuttgart, Tokyo, Torino, Trieste, Vienna, Wexford, and Zürich.