The main difference between Opera and the previous polyphonic vocal music is the unique melodic line, resulting from the merging of bass and singing. In polyphonic music different vocal lines work independently, overlapping one another and making a text often incomprehensible. Opera instead offered a new way for making words expressive and intelligible, by creating a single melodic line, supported by an accompaniment.
La Serva Padrona, composed on a libretto by Gennaro Antonio Federico in 1733, is an intermezzo divided into two interludes. It was originally designed to be performed between the acts of the opera seria Il prigioniero superbo by Pergolesi himself, staged at the Teatro San Bartolomeo in Naples on the occasion of the birthday of the empress Elisabeth Christine of Brunswick, wife of the emperor Charles VI and mother of the empress Marie Therese of Augsburg. That very same libretto had been used by almost every composer in Naples and therefore was already popular in a number of successful versions. The definition of believable characters and the solid realism of the short story, revolving almost entirely around the characters’ psychology made of the libretto a success. Pergolesi’s genius turned it into a masterpiece.
In Stendhal’s opinion Tancredi was Rossini’s best opera. In his biography he wrote: “there’s no bravery or grandeur in this opera but only the simple purity and virginity of genius”. The libretto by Gaetano Rossi was drawn from Voltaire’s tragedy Tancrede. For that libretto Rossini composed an innovative score, combining in an original way the baroque “extreme coloraturas” with the pre-Romantic simple melodies of the new belcanto.
Everywhere in the world, Italian language is popular thanks to music; not just Opera but also pop hits such as Volare or Mamma. Common Italian words are increasingly used in other languages while notation on music scores is traditionally in Italian (piano, forte, crescendo, rallentando etc…). So much so that many Italian terms used for music are now truly international, representing a substantial part of the international Italian vocabulary.