Following the
end of monarchy, the name was simplified to ''Teatro dell'Opera'' and, in 1958, the building was again remodeled and modernized. Rome City Council again commissioned architect Marcello Piacentini, who radically altered the building's style, notably with regard to the facade, entrance and foyer, each of these taking the form we know today. The theater's legendary acoustics still bear comparison with any other auditorium in the world. The seating capacity is about 1,600. The house was retrofitted with air-conditioning subsequent to a restoration, which provided improvements to the interior. The stucco work was completely restored, the great proscenium arch strengthened, and a parquet floor of solid oak blocks laid to replace the previous one. On 2 January 1958, the theater was the venue for a controversial performance of
Norma starring
Maria Callas in the presence of the President of Italy: for health reasons, Callas abandoned the performance after the first act (the opera company had not engaged an understudy). The post-war period saw celebrated productions, including
Mozart's
Le nozze di Figaro in 1964 and
Verdi's
Don Carlo in 1965, both conducted by
Carlo Maria Giulini and directed by
Luchino Visconti. In the 1950s and 1960s the Director was Riccardo Vitale (father of actress Milly Vitale). In 1992,
Gian Carlo Menotti was appointed artistic director of the Teatro dell'Opera di Roma, a post he maintained for two years before being asked to resign over conflicts with the theatre's managers involving Menotti's insistence of staging Wagner's
Lohengrin. From 2001 to 2010, the music director and chief conductor of the company was
Gianluigi Gelmetti. He was due to be succeeded in these posts by
Riccardo Muti, as announced in August 2009, but Muti demurred, citing in
La Repubblica in October 2010 "general difficulties that are plaguing the Italian opera houses". Later, Muti assumed a role similar to that of music director but without title. Notable productions under Muti have included Gluck's
Iphigénie en Aulide (2009), Verdi's
Nabucco (2011),
Simon Boccanegra (2012) and
Ernani (2013).
Daniele Gatti first guest-conducted with the company during the 2016–2017 season. He returned for subsequent guest engagements in each of the following two seasons. In December 2018, the company announced the appointment of Gatti as its new music director, with immediate effect. Gatti is scheduled to stand down as the company's music director on 31 December 2021. In June 2021, the company announced the appointment of
Michele Mariotti as its next music director, effective 1 November 2022, with an initial contract of 4 years. The name "Teatro Costanzi" remains officially in use, to refer to the main auditorium. ==Opera company's summer venue==