Listen to Organ Sonata No. 1 in E-Flat Major, BWV 525: I. Allegro moderato online. Organ Sonata No. 1 in E-Flat Major, BWV 525: I. Allegro moderato is an English language song and is sung by Ivan Sokol. Organ Sonata No. 1 in E-Flat Major, BWV 525: I. Allegro moderato, from the album Classical Bach 4, was released in the year 2017. The duration of the song is 2:55. Download English songs online from JioSaavn.