Anton Webern was the kind of student that seizes a teacher's idea and runs with it - a quality that can be both flattering and challenging to the teacher; as Arnold Schoenberg once observed: "I have to keep all of my new ideas secret from Webern, because he uses them before I do, and I thus find myself in the embarassing position of seeming to imitate my students." Thus when Schoenberg began to extend his harmonic explorations into atonality Webern was right there to push the concept into even more radical territory. The 1909 Five Movements for String Quartet are an early expression of the way he built interconnected motives into a crystalline texture, in which each facet has a distinctive shape, separate from yet resembling the whole. The result earns that overused adjective "unique" - as well as "frustrating," since the tightly interconnected facets mean that neither listener nor analyst can use the more linear medium of language to convey a sense of how this happens.

The first movement is in sonata form but is so tightly compressed that the narrative quality usually established by working out an initial harmonic opposition is absent; here, the listener is left with a more abstract impression of contrast. Webern was also a leader in the exploration of Klangfarbenmelodie, or tone color as melody; here, his tonal palette includes a range of unconventional instrumental techniques: using the wood of the bow to strike the strings, bowing up near the bridge, and harmonics. The second, extremely slow, movement uses the dissonant interval of a minor second (adjacent notes) to create a forward-moving harmonic friction. The third movement, a scherzo in nature if not in form, is over almost before it begins. Its use of pizzicato gives it a Mendelssohnian feel, an association turned eerie when followed by the supernatural quality of the fourth movement's slow tonal experiments and suggestive half-phrases. The fifth, longest of the miniatures, emerges from a barely perceptible impulse to a barely perceptible shape to an intense outburst before turning back into the shadows.

- Susan Key is a musicologist and frequent contributor to Los Angeles Philharmonic programs.