Listen to Symphony No. 1 in C Minor, Op. 68: I. Un poco sostenuto - Allegro online. Symphony No. 1 in C Minor, Op. 68: I. Un poco sostenuto - Allegro is an English language song and is sung by Boston Symphony Orchestra. Symphony No. 1 in C Minor, Op. 68: I. Un poco sostenuto - Allegro, from the album Brahms: Concertos, Symphonies & Dances, was released in the year 2015. The duration of the song is 12:56. Download English songs online from JioSaavn.