Listen to Piano Concerto No. 1 in E-Flat Major, S. 124: I. Allegro maestoso online. Piano Concerto No. 1 in E-Flat Major, S. 124: I. Allegro maestoso is an English language song and is sung by Julius Katchen. Piano Concerto No. 1 in E-Flat Major, S. 124: I. Allegro maestoso, from the album Dramatic Classical Collection, was released in the year 2014. The duration of the song is 5:14. Download English songs online from JioSaavn.