Weber whipped this piece out during a concert tour with his clarinetist friend Heinrich Joseph Bärmann. The two were to give a concert in Prague, where Weber hoped to have his opera Silvana produced. To advertise the opera's felicities to Prague's audiences, Weber wrote, rehearsed, and performed all in a single day a quarter-hour's worth of variations on the aria Warum musst' ich dich je erblikken. Weber had already worked variants on this tune into the fifth of his six "progressive" sonatas for violin and piano. The stately melody moves smoothly and gradually up the scale, pauses at a little trill, continues its ascent, and gently descends like a feather. It repeats its course around a couple of mildly contrasting little sections, then embarks on a series of flashy variations, or so one assumes upon hearing the first. The second is given entirely to the piano; upon its return, the clarinet is in a more thoughtful mood and offers a slow, highly expressive third variation. This approach holds steady well into the work's central portion, the clarinetist displaying virtuosity only in a brief passage of trills and wide leaps. The piano again takes a variation for itself, returning us to the realm of pure showmanship. Aside from one long, ominous detour, the ensuing variations are florid and stretch widely through the clarinet's range. Surprisingly, the set ends not with fireworks, but with a demure restatement of the original theme.

© All Music Guide