Listen to Piano Concerto No. 18 in B-Flat Major, K. 456: I. Allegro vivace online. Piano Concerto No. 18 in B-Flat Major, K. 456: I. Allegro vivace is an English language song and is sung by Baby Lullaby. Piano Concerto No. 18 in B-Flat Major, K. 456: I. Allegro vivace, from the album Classical Baby Songs – Smart Lullabies for Babies, Classic Music of Ludwig van Beethoven & Wolfgang Amadeus Mozart, was released in the year 2017. The duration of the song is 3:05. Download English songs online from JioSaavn.