Listen to Chamber Symphony in B-Flat Major: I. Allegro maestoso online. Chamber Symphony in B-Flat Major: I. Allegro maestoso is an Instrumental language song and is sung by Marina Butir, Alexander Rudin and Academic Chamber Orchestra "Musica Viva". Chamber Symphony in B-Flat Major: I. Allegro maestoso, from the album Bortniansky: Chamber Symphony & Three Romances - Benda: Concerto for Harpsichord and String Orchestra, was released in the year 2005. The duration of the song is 7:16. Download Instrumental songs online from JioSaavn.