Noam D. Elkies accompanies the Bach Society Orchestra on the piano for the Orchestra’s performance of “Choral Fantasy” in their Saturday concert.

In addition to teaching Mathematics 55, winning the prestigious Putnam Prize three times, and being the youngest person ever to become a full Harvard professor, Professor Noam D. Elkies has yet another accomplishment to add to his name. On Saturday, Elkies gave an awe-inspiring performance of Ludwig van Beethoven’s “Choral Fantasy” as part of the second concert of the Bach Society (BachSoc) Orchestra’s season.

The Sanders Theatre performance also featured several vocalists of the Harvard University Choir (UChoir) under the baton of Music Director Aram V. Demirjian ’08 and guest conductor Edward E. Jones. The combination of BachSoc, Elkies, and the University Choir made for a memorable and enjoyable evening.

The night began with the lower string instruments. They performed a slow Andante introduction to Felix Mendelssohn Bartholdy’s “Symphony No. 5 in D minor, Op. 107,” also known as the “Reformation,” before the rest of the orchestra joined them in the dramatic Allegro con fuoco section of the piece.

The music occasionally sounded a little too careful and restrained, especially at the beginning of the piece. Although the first movement started out rather sluggishly with intonation problems, the orchestra gradually built momentum towards the end. The work finally culminated in a series of strong, majestic (albeit rather brass-heavy) chords. The members of the orchestra, which included a slew of freshmen, breathed together impressively throughout the piece under Demirjian’s direction.

Jones, director of the University Choir, opened the second half of the concert with Johann Sebastian Bach’s Cantata No. 140, “Wachet auf, ruft uns die Stimme.” The rich sound of the choir, accompanied by the baroque bass lines of the orchestra, filled Sanders Theatre with the graceful and light mood of the first movement.

All of the instrumental and voice soloists performed very well, although some vocalists got off to a rather shaky start. Both the arias of the third and sixth movements aptly portrayed Bach’s duet between Christ and the Soul. The sustained notes were especially rich and skillfully conveyed a spiritual sense of love and longing. The charming two-note slurs of the oboe solo in the fourth movement complemented the well-phrased vocal lines with grace. The cantata culminated in a grand finale as the full voices of the choir soared above the orchestra.

The highlight of the night was definitely Elkies’s wonderfully sensitive performance of Ludwig van Beethoven’s Fantasia for Piano, Chorus, and Orchestra in C minor, “Choral Fantasy.” After staff moved the piano to nest within the orchestra, the audience awaited Elkies’s appearance with almost palpable anticipation.

“Choral Fantasy” started with a cadenza-like, improvisatory section for unaccompanied piano. Elkies’s dramatic opening begged for more dynamic contrast, but by no fault of his own. For logistical purposes, the top of the grand piano had been removed, which drastically reduced the projection of its sound into the audience. However, this shortcoming did not severely diminish the introduction’s effectiveness—especially since Elkies was very sensitive to the ends of his phrases, often tapering off in delicate pianissimos.

The orchestra and the piano passed the main melody of the work back and forth in a well-voiced dialogue throughout the piece. Demirjian’s direction deftly brought out the layered texture of the pizzicato from the strings, melodic lines from the woodwinds, and Elkies’s impressively controlled trills, especially after the entry of the chorus.

There were noticeable intonation problems throughout “Choral Fantasy”—especially in the brass and violin sections—and minor issues with the ensemble of the piece, particularly during the performers’ entrances.

However, the overall effect of the work was almost mythic. The waves of sound continued to build to the end of “Choral Fantasy” with the full grandeur of the choir’s pure harmonies, the strings’ furious tremolo, and Elkies’s intense scales and arpeggios. The evening as a whole was similarly fantastic.