Listen to Piano Sonata No. 3 B-Flat Major, K. 281: III. Allegro online. Piano Sonata No. 3 B-Flat Major, K. 281: III. Allegro is an English language song and is sung by Baby Lullaby. Piano Sonata No. 3 B-Flat Major, K. 281: III. Allegro, 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 3:33. Download English songs online from JioSaavn.