Listen to Prelude, Op. 28, No. 15 (Sonidos de la Naturaleza) online. Prelude, Op. 28, No. 15 (Sonidos de la Naturaleza) is an Unknown language song and is sung by Calm Music for Studying. Prelude, Op. 28, No. 15 (Sonidos de la Naturaleza), from the album Study Music: Calming Relaxing Instrumental Music for Focus On Learning and Mozart Effect, was released in the year 2014. The duration of the song is 4:44. Download Unknown songs online from JioSaavn.