The Eggner Trio made its splendid, often thrilling, American debut Thursday at the Inter-American Development Bank in two important works by the musicians' Austrian compatriots: "Wem Gehoert der Mensch?" ("To Whom Does Mankind Belong?"), from 1988, by Werner Pirchner, who died last year at age 61; and the Trio in E-flat, D. 929, written by Franz Schubert in 1827, the year before he died. The event was one of the bank's excellent 6:30 p.m. concerts, offered to downtown workers who want to avoid the brunt of out-bound traffic.

The trio is a truly fraternal threesome of brothers -- Christoph (piano), Georg (violin) and Florian (cello). Like Schubert, who spent his youth playing in his family string ensembles, the Eggners play with an intense, musically impassioned togetherness, putting behind them any conflicts that might have erupted among siblings living in close quarters and with similar gifts.

In English, the six subtitles of Pirchner's work have the tang of 1970s counterculture, as in "The People Belong to the State. The Reverse!" At a first hearing minus a score, the division between sections wasn't always audible. Yet the Eggners' high-energy wit made the diversity of Pirchner's styles unmistakable: percussive, driving jazz syncs alternating with the Moorish traces in Iberia's melodies. The musicians brought overwhelming conviction to the desolate pathos of Schubert's Andante and final Allegro.

-- Cecelia Porter