The purpose of this study is to discover the reasons why Beethoven's last two violin sonatas are so different from one another. There are two main reasons for this difference. First, his life experiences altered his compositional style and the direction in which his music was going. After Beethoven wrote the Heiligenstadt Testament, his music became more forceful and intense. His Violin Sonata No. 9 was strongly affected by this mood and is part of his "heroic" works. Unlike the Violin Sonata No. 9, his Violin Sonata No. 10 is related to his love for his "Immortal Beloved." The Violin Sonata No. 10 is lyrical and calm, and one of the non-heroic works. Second, aside from some of Beethoven's violin sonatas, the sound of his compositions became more forceful, and generally all the sonatas expanded in length. However, the more compact Violin Sonata No. 10 stands alone in the genre.