Listen to Sonata for Two Violins and Basso Continuo in B-Flat Major, RV 78: I. Preludio adagio online. Sonata for Two Violins and Basso Continuo in B-Flat Major, RV 78: I. Preludio adagio is an English language song and is sung by Various Artists. Sonata for Two Violins and Basso Continuo in B-Flat Major, RV 78: I. Preludio adagio, from the album 100 Best: Vivaldi, was released in the year 2016. The duration of the song is 1:09. Download English songs online from JioSaavn.