There aren't too many classical concerts where you find a member of the orchestra's woodwind section sitting a couple of seats away from you, playing his instrument.

That is what happened on Friday evening at the Ordway Center for the Performing Arts, as the St. Paul Chamber Orchestra opened its 60th anniversary season with a performance of the American composer Terry Riley's "In C."

"In C" is a totemic piece, credited with launching the musical movement we now know as Minimalism, which uses repetitive patterns of small melodic cells to create broader sonic canvasses.

The piece leaves a lot of decisions to the performers, such as when to stop and start each of the 53 modules Riley provides as raw materials to make the music happen.

The SPCO took that freedom and walked with it, placing some of its members at the rear of the auditorium and on the balconies and having them move among the audience as they played.

The effect was to heighten appreciation of how intricately intertwined the strands of Riley's do-it-yourself masterpiece became as the piece developed, and how distinctively individual voices contributed within its apparently homogenized textures.

Half a century after it was written, "In C" emerged as a strangely democratic message in these fractured times, a metaphor for how a multitude of contending voices can still combine in a teeming unity of common purpose.

Another American work, Samuel Barber's "Knoxville: Summer of 1915," came after intermission. Where "In C" tilts with unbowed optimism toward a brighter future, "Knoxville" clings achingly to a past that somehow seemed better but will never come again.

Its vision of an America where "people sit on their porches, rocking gently and talking gently" was vividly re­created by soprano Julia Bullock.

There's a danger of over­doing the sepia-tinted nostalgia in "Knoxville," but Bullock avoided it. Her recollection of the idyllic summer evenings referred to in James Agee's text was heartfelt but moved purposefully toward the dramatic crisis of identity that comes later in Barber's setting.

Bullock's voice, clear-spoken and intimate in the balmy opening, turned urgent and operatic as the narrator wondered "who shall ever tell the sorrow of being on this earth."

It was a grippingly coherent piece of singing, crisply accompanied by the SPCO players, with particularly evocative solos from guest bassoonist Brad Balliett.

Beethoven's "Emperor" piano concerto seemed a conservative choice of repertoire to end the concert, after two pulsating slices of Americana. But that was to reckon without the alchemical powers of SPCO artistic partner and pianist Jeremy Denk, who has the knack of making old, familiar pieces seem fresh and newly minted.

Denk's interpretation tingled with spontaneity, some of it apparently improvised.

The finale was particularly rambunctious, Denk digging scrunchily into Beethoven's bounding rhythms like a cowboy at a barn dance.

Denk's legato playing was exquisite, and as an encore he reeled out a cheekily inflected performance of Beethoven's Variations on "Rule Britannia." It was outrageously enjoyable.

Terry Blain is a freelance classical music critic for the Star Tribune. Reach him at artsblain@gmail.com.