Piano Trio - Level 3 - Digital Download SKU: A0.532280 Composed by F. Sor. Arranged by Klas Krantz. 19th Century,Classical,Romantic Period. 6 pages. Amadeus Music #4596677. Published by Amadeus Music (A0.532280). Fernando Sor (1778–1839) was a Spanish classical guitarist and composer. While he is best known for his guitar compositions, he also composed music for a wide range of genres, including opera, orchestra, string quartet, piano, voice, and ballet. His ballet score Cendrillon (Cinderella) received over one hundred performances. Sor's contemporaries considered him to be the best guitarist in the world.