When they are on stage together, Rohan Smith and Eva Gruesser treat each other solely as professional comrades. They are serious about their task at hand, and committed to making their performance as good as it can possibly be.

Offstage is a different story.

Smith, who conducts the Midcoast Symphony Orchestra, and Gruesser, a violinist, are husband and wife. The New Hampshire couple met in 1977, and have been married since 1988. She joins his orchestra as a guest soloist for the season finale, set for Saturday in Lewiston and Sunday in Topsham.

“Our musical personalities are what people see on stage,” said Smith.

Added Gruesser, “When we play together, we don’t really think about each other anymore. We think about the piece, the context, the execution, how to play it, how to master it. It’s all about serving the music. There is no room to be concerned about each other.”

Gruesser will perform Prokofiev’s Violin Concerto No. 2 in G minor. The orchestra will also perform Mozart’s “Cosi fan tutte Overture” (“The School for Lovers Overture”) and Cesar Franck’s Symphony in D minor.

 Performances are 7:30 p.m. Saturday at the Franco-American Heritage Center in Lewiston and 2:30 p.m. Sunday at the Orion Performing Arts Center in Topsham.

The Prokofiev concerto is among the most recorded concertos from the 20th century, Smith said. Gruesser, who was born in Germany, first performed it 38 years ago, when she was 19.

“Over four decades, you have become a new musician,” she said. “The youthful skills were great, and served you well at 19. Now you are so much more aware of different things. There is much more depth and sound consciousness.”

Gruesser is looking forward to the performance so she can discover new elements of the piece, which she described as “beautiful with songful melodies” and full of “magical fantasy.”

This weekend’s performances mark the second time Gruesser has performed with Smith at the helm of the Midcoast Symphony. Concertmaster of American Composers Orchestra at Carnegie Hall, she has performed as soloist, chamber musician and concertmaster throughout North America, Europe and Australia.

In the 2006-07 concert season, Gruesser performed with Wynton Marsalis and the Jazz at Lincoln Center Orchestra in collaboration with American Composers Orchestra. In 2012, she performed at Bowdoin College in Brunswick with pianist George Lopez.

She has also performed as guest concertmaster with many orchestras, including the Sydney Symphony Orchestra, the Australian Opera and Ballet Orchestra, the Brooklyn Philharmonic Orchestra, the Stamford (Conn.) Symphony Orchestra and the Long Island Philharmonic. She was concertmaster of the New Hampshire Symphony Orchestra from 2002 to 2007.

Staff Writer Bob Keyes can be contacted at 791-6457 or:

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