Taddei first studied architecture, then singing at the Accademia Sant'Agostino in Genua and at the opera school at La Scala.
He made his debut in 1965 (other date 1964) at the Maggio Musicale
in Firenze as Belzebub in Doktor Faust conducted by Fernando Previtali. Taddei won a vocal competition in Firenze (1966).
He had his first successes in Italy. In 1968, he sang in Ankara in Anna Bolena and Tosca, and toured
Praha, Brno, Bratislava, Košice, etc with Rigoletto, La traviata, Madama Butterfly, and Lucia di Lammermoor.
He sang at La Scala, at the Conservatorio in Milano, at La Fenice, at the Massimo (Palermo), at the San Carlo, at
the Verdi (Trieste),
in Modena, Ferrara, Reggio Emilia, ...
In 1971, he took part in the world premiere of Fontana by Mario Bugamelli in Trieste.
He took part in RAI concerts and in television programs in foreign countries.
He also sang in France (Nice, Bordeaux), Sofia, Madrid, La Monnaie.
He recorded for Fratelli Fabbri (Madama Butterfly with Raina Kabaivanska), BASF and Supraphon.
Reference: Kutsch & Riemens