Symphony in C ended its season Saturday with two works that demand explanation bracketing a work that requires none at all. The Mendelssohn

Violin Concerto

glowed in the middle of this program like a jewel in a forest of vines and dark leaves.

But those outer works insisted on the closest attention, for both Schumann's late Manfred Overture and Arnold Schoenberg's orchestration of Brahms' Piano Quartet in G minor lurk at the edge of the repertoire, posing stylistic questions and interpretive gestures. Conductor Rossen Milanov builds programs to reward the faithful, but also to make them sit up straight while the music grows around them.

Schumann's incipient insanity is always mentioned with Manfred, for the music portrays a figure beset by despair and longing for death. There is also, in the overture, homage to Beethoven, from the first three chords to the declarative E-flat tonality from Beethoven's Eroica. Controlling those musical winds tests any orchestra's mettle, and much of the performance seemed a realization of notes and big moments without an accompanying mining of depths and narrative shadings. Milanov effectively argued against tiresome prevailing criticism of Schumann's orchestration. His soloists were agile and expressive, and his direction allowed inner voices to play attractive roles.

Separated by a generation, Schoenberg had a close - intellectual - history with Brahms, writing that Brahms was the first modernist, thus closer to Schoenberg's crusade for freeing music from the fetters of tonality. When Schoenberg orchestrated the G minor Piano Quartet, he was embodying criticism of chamber music performance levels, but also chiding Brahms for not having heard the inner grandeur of his own ideas. Audiences instantly take sides: Hearing Brahms expanded with trombones, bass clarinet, piccolos and even tuba asks new ears. Milanov's orchestra found spirit in hearing the horns finish a familiar violin melodic line, or in building sonorities Brahms never imagined. The solo players seemed especially refreshed, and the appearance of familiar instrumental colors approached sly humor.

Mendelssohn had no philosophical thesis concealed in E minor. His Violin Concerto celebrates melody and sensitive playing. Violinist Augustin Hadelich gave the work melodic gloss and technical finesse. He was playing a much-advertised Stradivari instrument that seemed voiced for 19th-century ideals of subtlety and clarity. His playing energized every note in the line, balanced the sound with the orchestral sections and seemed to let Mendelssohn speak for himself. Lest anyone fail to notice his extraordinary technical command, Hadelich elicited gasps with his encore playing of Paganini's Caprice No. 5.