Everyone in the Dresden Chamber Orchestra stands up during a performance -- except, of course, the cellists, who can't. Their posture may have contributed something to the special vigor with which the 20-piece string orchestra played last night in the Terrace Theater.

Whatever the reason, the sound was robust and the playing was muscular right from the beginning, in the fast opening movement of Boccherini's Symphony No. 1 in D, and the ensemble was especially impressive throughout the evening whenever the music called for athletic prowess.

It was most seriously required -- and most brilliantly presented -- in the Chamber Symphony, Op. 110, of Shostakovich, which was substituted at the last minute for something called "Visionen" ("Visions") for Strings by the East German composer Siegfried Matthus. We must wait for another visit by the Dresden musicians to hear this work, which is dedicated to the orchestra's conductor, Manfred Scherzer. But it is hard to imagine that the substitution was not an improvement. Arranged for string orchestra (by Rudolf Barshai) from Shostakovich's tense, violent, introspective and autobiographical Eighth String Quartet, the Chamber Symphony is one of the most powerful works for string orchestra to emerge from the last generation. With 20 pieces playing in the intimate acoustics of the Terrace, it had in full measure the larger-than-life quality that has been always implicit in the string quartet version.

The orchestra is also capable of sweet tone and delicate phrasing, as it showed in the Boccherini slow movement and the opening of Mendelssohn's Symphony No. 10 for strings. Written when the composer was a 14-year-old prodigy, this work also evoked the Dresden group's vigor in its closing section, which I have never heard played more impressively. The energy was tautly controlled in Mozart's Adagio and Fugue in C minor, and the music's emotional impact was heightened by the intense discipline with which it was played.

Mozart also provided the last item on the agenda: "Eine kleine Nachtmusik," which was played with precision -- all the music really needs to work its magic, though it can yield even further delights with a little waywardness in the phrasing.