I’m just back from the best chamber music program I’ve heard so far this season.

The ATOS Trio — violinist Annette von Hehn, cellist Stefan Heinemeyer and pianist Thomas Hoppe — are now in their seventh season as an ensemble. They play with technical mastery, remarkably tight ensemble, and spirited, nuanced musicality.

Mendelssohn’s Trio No.2 in c minor, Op.66, opened the program, sporting dizzying virtuoso playing in the scherzo and unerringly melodious charm throughout. Gaspar Cassadó’s Trio in C Major sounds very much like a compositional fusion of his two teachers, Ravel and Falla; the ATOS convincingly delivered this delightful work in its “original Spanish.” Schubert’s Trio No.2 in E-flat Major, D929, is one of his finest chamber works, and while the ATOS favors tempos in this work that are on the swift side of the spectrum, the music never seemed rushed; the oversize “rondo on steroids” finale has always struck me in concert as in need of an editor — until this evening, that is, when the ATOS reined in its ramblings and made edifying sense of the finale. In the encore, the trio version of Kreisler’s Marche miniature Viennois, von Hehn and Heinemeyer’s stunningly unified portamenti had my jaw dragging on the ground.

The venue was the elegant but sometimes strident-sounding Weill Hall, the recital hall upstairs in the east wing of Carnegie Hall, but the ATOS made a gloriously sweet, full-bodied sound that never sounded shrill even in the loudest passages.

It’s worth noting that the hall was filled to capacity this evening.  A buzz has been beginning to build around this impressive ensemble, and it’s well deserved. If you have an opportunity to see the ATOS Trio, I recommend you run — don’t walk — for tickets.