Beethoven’s late piano sonatas, string quartets and other creations also reflect the changes in his style, the most obvious of which can be summarized in the following aspects: 1. Lyricality and introspection to a large extent replaced the heroic nature of the past. Such as the vocal suite "To a Lover in the Distance", piano sonatas in E minor (Op. 90), A major (Op. 101), C minor (Op. 111,) and string quartet Op. 127, 131, etc.

2. Abstraction and complexity have largely replaced the titles of previous works. In his later years, Beethoven's resentment against reality and his pursuit of reason and peace, as well as his struggles and reflections, and other contradictory experiences were expressed in a deeper, more complex, and more abstract way. His later works made greater use of contrapuntal textures and polyphony to express these experiences. In a sense, this is also the harvest of his years of experience in studying Bach's compositions.

3. In terms of structure, many of Beethoven's late works broke the classical tradition. For example, the Piano Sonata Op. 111 has only two movements, while the String Quartet Op. 131 has seven movements. In addition, Beethoven more consciously broke and blurred the boundaries between paragraphs, giving the music a lasting effect and changing the style characteristics of classicism with clear structures and distinct paragraphs. Many of his specific practices were inherited by romantic composers of the 19th century.

In the classical period of European music history, among Haydn, Mozart, and Beethoven, only Beethoven entered creation after the French Revolution. His life experienced Europe's transition from feudalism to capital. During several important stages of the drastic change of socialism, the formation of his world view, artistic outlook and music creation were closely related to the turbulence of the entire society and the ideological trends of Germany and Austria at this time. Beethoven's works are essentially different from those of the previous two masters. He is both the master of classical music style and the founder of romantic music style. It can be seen from him that the social status of German and Austrian composers who grew up in the era of Enlightenment and the French Revolution was changing, and they had a more conscious understanding of the social status of free artists. His creations have a strong individualistic tendency and express personal experiences and thoughts. Beethoven developed the classical tradition in technique, especially his contribution to the sonata symphony suite. And he blurred the boundaries between movements or paragraphs, many works have the concept of sound-picture or title music, used human voices in symphonies, and modified and improved small genres, etc., which shows that he has adopted or It foreshadows certain characteristics of the Romantic music style.