"Good-bye, great artist. Truly yours, Beethoven" is the quote that concludes a letter Beethoven wrote to his friend Romberg on February 12, 1822. The two were indeed friends, and Beethoven greatly admired and respected Romberg as a musician and composer. The three Sonatas op. 5 for harp and cello (or violin), published in Paris in 1803. In essence, these compositions are three large concertante sonatas, each of which is articulated in three movements. The musical material is distributed evenly between the two instruments, in order to create a continuous dialogue between them. The writing, for its time, is to be considered at the limit of virtuosity. Romberg occupies his indelible place in history, not only for his musical importance but for all the innovations he brought to cello technique, didactics, and even of the construction of the instrument itself.