If the composer, with his unusual grasp of harmony, his love of the graver movements, would aim at natural rather than strained or recherché composition, he would set good work before the public, such as would throw into the shade the stale, hurdy-gurdy tunes of many a more talked-about musician.The Opus 11 trio is written for clarinet, cello and piano and was published with a part for violin instead of the clarinet for use by amateur musicians. Of course the late 18th century had no sound recording technology, so the only way music lovers could hear compositions were by playing them themselves or hiring professional musicians which only the rich nobility could afford. There were some complaints about the difficulty of Beethoven's compositions, but they still sold well.
The trio was written and published in 1798 and is in 3 movements:
I. Allegro con brio - The trio begins with a unison statement of the first theme. The rest of the themes in the exposition come one after the other and it is difficult to tell what is a theme and what is transitional material, quite similar to what Mozart did (and Beethoven was a great admirer of Mozart) in some of his expositions. There is a full close that does mark at least divides the themes into two groupings. The exposition is repeated and with such a wealth of thematic material, it needs to be to help the listener grasp what is going on. The development section begins with one of the secondary themes, with a variant of the opening theme following, along with development of it. The recapitulation consists of some of the secondary themes going through Beethoven's highly individualistic modulations until a short coda is reached that abruptly ends the movement.
II. Adagio - The cello sings the opening theme first, then the clarinet. The piano makes its own statement after the two solos, then the instruments gently play off each other. A most satisfying, gently moving interplay between the three instruments keeps the music moving towards the gentle close done by the piano.
III. Allegretto - This is a set of variations on a tune from a popular opera of the time, The Corsair In Love by Joseph Weigl, which premiered in 1797. The tune is called Pria ch'io l'impegno - Before beginning this awesome task, I need a snack. Some credited Beethoven's publisher with suggesting the tune to Beethoven, others credit the idea to a clarinetist that commissioned the work from Beethoven. Whatever the circumstance, it was one of the few times Beethoven used another composer's music for a set of variations. This tune is the basis for the nickname of the trio, Gassenhauer or Popular Song trio. Beethoven writes nine variations full of surprises on the tune and a quirky finale that is no less surprising.