The Mt. Vernon Chamber Orchestra closed its season Saturday night with three delightful works performed in the complementary acoustics of St. Louis Catholic Church in Alexandria.

The first was Howard Hanson's short Serenade for Flute, Harp and String Orchestra (Op. 35). A crisp, rhythmic figure from the harp, nicely articulated by Kristin Jepperson, opened the work, but the texture quickly became soft and malleable. Hanson, a self-confessed romantic and proud of it, relied on rather conventional effects throughout, such as impressionistic harmonies and colors and exotic "snake charmer" intervals for the flute. These would have become monotonous in a longer work, but just as the ideas began to pall, the piece ended with a charming flourish from the flute. It was enough of a modestly good thing.

Flutist Lynn Ann Zimmerman gave careful consideration to phrasing and varieties in tone color: Her playing was always interesting. The tone did become breathy on top, however, and some of the sweeping upward scales were weak at the peaks. The strings played acceptable accompaniment, but there was some poor intonation, which was masked by the echoes and resonance in the church.

Shostakovich's Incidental Music to Hamlet (Op. 32) is far more interesting than the title suggests. Thirteen short movements, with titles such as "Funeral March," "The Banquet" and "Ophelia's Song," show remarkable variety in the service of underlying thematic and rhythmic unity (the simple pattern of "long-short-short long-short-short" permeates the work, as it does the composer's magnificent Fifth Symphony). All in all, it is first class Shostakovich. The only drawback is that it is not a suite, but rather a collection of pieces that, in the context of a play might sound perfectly natural, but in a concert setting tended to end abruptly.

The instrumentation, heavy on low brass and percussion, proved perfect for the space, and the tuba and double bass sounds were felt in the chest as well as the ear. Except for some string tuning problems and occasional missed horn attacks, the performance was good.

Conductor Ulysses S. James did an admirable job of keeping the humorous aspects of the work -- the quirky little dances and the odd poignancies -- in the forefront. Seeing a production of Hamlet with this music would be a treat.

The final work was Mozart's Piano Concerto No. 9 in E-flat Major (K. 271). Soloist Betty Bullock gave a remarkably graceful and carefully understated performance of this sublime and subtle work. Using a small Weber grand, she played quietly as though to make the audience listen. And it worked. There were no pyrotechnics -- none were needed.

Bullock's ornamentation and trills were even and ingratiating, and her rhythmic pacing of the many recitative-like sections was excellent. The final cadenza in the third movement could have had more fire, but perhaps that would have diminished the gentle effect. It was a fine performance that served Mozart very well indeed.

For the most part, the accompaniment from the small orchestra was adequate, and sometimes inspired. But problems with tuning and articulation were more apparent here in the refiner's fire of Mozart's delicacy than in the other, more brash and forgiving works.