Listen to Violin Concerto in B-Flat Major, TWV 51: B1: IV. Allegro online. Violin Concerto in B-Flat Major, TWV 51: B1: IV. Allegro is an Instrumental language song and is sung by Mikhail Vaiman, Lev Shinder and Leningrad Philharmonic Chamber Orchestra. Violin Concerto in B-Flat Major, TWV 51: B1: IV. Allegro, from the album Mikhail Vaiman: Selected Recordings, Vol. 2, was released in the year 2005. The duration of the song is 2:20. Download Instrumental songs online from JioSaavn.