Lukas Foss' Capriccio is a short piece, lasting only about six minutes total. It is easy to hear the influence of other American composers, particularly that of Aaron Copland. The opening theme sounds like it is straight out of a Western film or ballet, such as Billy the Kid. The cello plays the energetic theme as if to set the stage for events to come. When the piano takes the melody, the cello uses rhythmic and playful double stops across the four strings, soon adding special bow effects and pizzicato to enhance the liveliness. Cello and piano continue to exchange melodies, and then the first melody comes back to interrupt the flow of the double stops. The piece then makes a transition to an expressive cello theme. This makes use of the lower range of the instrument, in addition to the upper register.
From here, Foss develops the theme, clipping along in his rhythmic and playful manner, adding a little bit more storminess and gaining in rhythmic and melodic complexity as he goes along. Throughout all of this, the first melody periodically comes back, explosively interrupting the various musical textures. Foss always makes use of the various ranges and dynamic capabilities of the two instruments, creating excitement and drama. Harmonics are used to create a special texture in the cello part at several points. The piece hits a major high point as the cello screams out in the upper register while the piano has crashing chords, and then everything drops immediately to almost nothing, ready to start over again.
Next comes a brief but expressive cello line, followed by the same type of double stop passage that occured earlier in the piece. Once again, the playfulness returns to form a brief coda of sorts. The first melody returns with a final flourish, then fades quickly to an ending that is a good deal calmer than the rest of the piece.
Foss' Capriccio is a very popular work among cellists performing twentieth century works. Its energetic drive and virtuosity makes the piece a lot of fun for performers and audiences alike.
It was written for cellist Gregor Piatigorsky, but dedicated to the late Natalie Koussevitsky, the first wife of Serge Koussevitsky. At the time of its composition, Foss was the pianist for the Boston Symphony under Koussevitsky. The piece was premiered at Tanglewood in 1946 by Piatigorsky and Foss and was well received. Twelve years later, the two recorded the Capriccio.