“Chamber music” can be an evasive term. Definitions tend to be slippery. Strict constructionists exclude the solo piano. Goodbye, too, to many of Mozart’s serenades and divertimenti; they’re meant for the outdoors.

Technically, the phrase derives from the German word


—music designed to be played in the home for the personal enjoyment of its performers and/or an intimate audience. That definition worked pretty well until the 19th century. Then things got a lot trickier with the growth of a middle class, the development of concert halls and the vast increase in size of an educated, demanding new audience.

And a knotty problem arose: When does chamber music cease to be chamber music? What happens when chamber music gets too big for its britches?

The Santa Fe Chamber Music Festival occasionally ran into this issue, notably in 1997—before the present regime arrived—with the staged premiere of Bright Sheng’s opera,

The Silver River

. While the performance was a success, many questioned its place among the festival’s more narrowly defined repertory. Since then, such relatively large offerings have become very much the exception.

Happily, the second week’s opening concerts proved to be exceptional in every possible way: a reading of Mahler’s massive symphony

Das Lied von der Erde

in the reduced scoring begun by Arnold Sch%uFFFDnberg and completed by Rainer Riehn in 1983. Instead of Mahler’s huge orchestral forces, the reduction requires 15 instrumentalists plus two singers and one conductor. The purpose of the reduction? Ostensibly to make this immense work more available to the general public. Subversively, maybe, Sch%uFFFDnberg was reacting against the sprawling late-romantic symphonic forms Mahler epitomized.

The July 25 performance was focused, clear, clean—everything that full-blast Mahler often isn’t. David Zinman led his polished crew with authority and grace. Tenor Paul Groves tossed off his three high-ranging songs effortlessly, despite a minor wardrobe malfunction. Mezzo Susan Graham was less comfortable; we generally hear a darker voice in the piece. But she sang with aplomb and her customary intelligence.

It’s not usual to link Mahler with quintessential American composer Charles Ives, even though the Viennese composer spent a certain amount of time in this country. But Jeremy Denk, who’d taken the piano part in

Das Lied

, made some valuable connections between the two at the July 27 concert featuring a single work:

Ives’s thorny, lengthy Sonata No. 2: Concord, Mass., 1840-1860. In a lucid prefatory talk, Denk suggested similarities between the two composers and went on to a brief movement-by-movement commentary—a model of musical explication.

Denk’s performance of this fascinating sonata was equally lucid. As is usual with Ives, the work is a marvelous stew, filled with allusions ranging from Beethoven through Wagner to Stephen Foster, dotted with ragtime, hymn tunes, patriotic melodies—the whole many-multi-layered shebang and, sometimes, all of them at once.

Denk inhabited and informed the four musical portraits that make up the sonata: “Emerson,” granitic and dense; “Hawthorne,” impish, impulsive; “The Alcotts,” a picture of orderly domesticity; and “Thoreau,” an impressionistic Walden Pond reverie. The near-capacity audience, myself included, was bowled over.

As we were on July 29, with a performance of Ravel’s Violin and Piano Sonata No. 2. The program opened with just-OK readings of two minor works: Robert Schumann’s “M%uFFFDrchenbilder” and a Schubert Divertimento for Piano, Four Hands. But when pianist Kuok-Wai Lio and violinist Cho-Liang Lin took charge of the Ravel, the electricity crackled. From its opening Allegretto with oriental overtones, through a Gershwinesque Blues, to the exhilarating calisthenics of the Perpetuum mobile, the duo played with style and exquisite insight.