Listen to Serenade No. 9 in D Major, K. 320: IV. Rondeau. Allegro ma non troppo online. Serenade No. 9 in D Major, K. 320: IV. Rondeau. Allegro ma non troppo is an English language song and is sung by Various Artists. Serenade No. 9 in D Major, K. 320: IV. Rondeau. Allegro ma non troppo, from the album A Classical Wedding: Honeymoon Relaxation, was released in the year 2014. The duration of the song is 6:01. Download English songs online from JioSaavn.