When Mozart began writing violin sonatas, the instrumental balance in the medium was weighted heavily on the keyboard side - many early examples, in fact, were bluntly labeled as keyboard sonatas with optional violin accompaniment. Mozart was one of the first composers to even things out in terms of full participation for both parties in the exposition and development of musical arguments.

In Arnold Schoenberg's last instrumental piece, the scale is tipped over to the violin side. Composed in 1949 and dedicated to the memory of violinist Adolph Koldofsky, the Phantasy "for Violin with Piano Accompaniment" is very precisely titled - the violin part was even written first, and the accompaniment added later.

The Phantasy is an intense, virtuosic rhapsody in a single movement, but containing within it episodes that clearly recall archetypes of other traditional forms, including a complete little Scherzo and Trio crisply bouncing in 6/8 rhythmic games. Schoenberg is meticulous about dynamic and expressive indications, including romantic markings such as passionato, dolce, cantabile, grazioso, and furioso. Variation is a central principle in composing with 12-tone rows, and there is also a very clear sense of theme-and-variations here, including a tight, dramatic recapitulation.

- John Henken is the Los Angeles Philharmonic's Director of Publications.