SAN FRANCISCO -- One recent sun-drenched morning, music poured from the windows of a stately home with a million-dollar view of the bay. It was Michael Tilson Thomas at the piano: MTT, as he is known, entertaining his neighbors by playing a little Liszt -- a piece he soon will perform at his 70th-birthday concert at Davies Symphony Hall, part of his 20th season with the San Francisco Symphony.
That season starts Wednesday with an Opening Night Gala, one more showcase for this icon of classical music. Among the world's leading conductors, few others enjoy such a long and fruitful relationship with a great orchestra. That fact isn't lost on Tilson Thomas, who -- getting up from the piano to talk about his storybook life -- spoke of his orchestra's steady ripening, its "elegance" and "lustrous" sound, as if he were describing a marriage that keeps on getting better.
"I think it's kind of special that, after 20 years, we can be enjoying these qualities of one another," he said. His orchestra continues to surprise him, grabbing his suggestions, only to take off and "absolutely make a piece its own."
Tilson Thomas, whose early mentors included Igor Stravinsky and Leonard Bernstein, is celebrated for his refined yet questing interpretations of Mahler, Beethoven and other masters. "He's an agitator who is able to bring the establishment to him, and make the traditional concert feel new," commented pianist Jeremy Denk, who will be part of January's 70th-birthday program.
He also is known as a high-tech innovator in the concert hall. Tilson Thomas' multimedia treatments of classic works by Debussy, Bartók, Britten and others -- this season it will be Beethoven's turn -- have become an exciting staple of recent seasons at Davies.
Outside the concert hall, he has wide-ranging tastes. In the living room of his eclectic arts-and-crafts-style home in the Cow Hollow neighborhood, which he shares with longtime partner and manager Joshua Robison, there's a vintage poster of his grandmother Bessie Thomashefsky. She was an actor and founder of the Yiddish theater in New York, whose example helped shape Tilson Thomas' notions of the musician as a kind of actor-performer. One of singer James Brown's black sequin jackets is on display, too; in the early '70s, the conductor spent a week on the road with Brown, in whose music he hears "the fierce excitement of being alive."
Asked to name his favorite songs, Tilson Thomas, who grew up in Los Angeles, is likely to mention ones by Franz Schubert, Duke Ellington, Laura Nyro and Brian Wilson of the Beach Boys. But for all his wide-open listening, his fresh performances of classic repertory stand at the heart of Tilson Thomas' reputation.
Violinist Alexander Barantschik -- the San Francisco Symphony's concertmaster since 2001 and one of the conductor's confidantes -- likened a Tilson Thomas performance to a pointillist painting by Seurat, with attention to "the smallest, tiniest, most microscopic details. Michael will ask, 'This little grace note in a scherzo -- what does it mean?' What does it mean? Who cares! But these details pile up until you step back and see this incredible picture."
Pianist Yuja Wang, who will perform at Wednesday's gala along with singer Bonnie Raitt, called the conductor "a polymath" who is "able to connect countless dots, to cross-pollinate ideas ... to reinvent."
"If he were in Hollywood, he'd be a director," said young Oakland-based composer Samuel Carl Adams, whose "Drift and Providence" is to be performed by Tilson Thomas and the San Francisco Symphony in November at Carnegie Hall. "He knows exactly what he wants, and he knows exactly how to put it together."
For his 20th season, Tilson Thomas will return to his first season's emphasis on American composers, both old (Charles Ives, Aaron Copland) and new (Mason Bates, Adams). In December, the orchestra will open a new "SoundBox" performance space with flexible seating and a cabaret vibe. The renovated Davies rehearsal room will be a home for new music played by small groups of the symphony's musicians, incorporating audiovisual and high-tech elements. The project "has Michael's fingerprints all over it," said Brent Assink, the symphony's executive director.
But in mulling over the 2014-15 season, Tilson Thomas -- who spoke in long, thoughtful paragraphs, while his miniature poodle Maydela snoozed on a nearby sofa -- kept coming back to lifelong loves.
These include the composer Robert Schumann and his private, songful world, with which the conductor feels a special intimacy, as if he could open a door and walk inside it. And then there is Beethoven, whose Missa solemnis -- a massive work for orchestra, chorus and solo voices -- is one of Tilson Thomas' favorite pieces. After several years of planning, he will conduct a multimedia production of the opus in June, 2015, incorporating actors, dancers, stage sets and visual projections. A confident man, Tilson Thomas sees it as a way of shedding new light on the layers upon layers of swirling activity in Beethoven's score. The new treatment should help clarify Beethoven's music for the audience, he said, while allowing the San Francisco Symphony "to really go after it with the ferocity which he for sure desires."
You will notice that Tilson Thomas spoke of Beethoven in the present tense.
Contact Richard Scheinin at 408-920-5069, and follow him at Twitter.com/richardscheinin.
Their 20th season together
Opening Night Gala with soloists Bonnie Raitt and Yuja Wang: 8 p.m., Sept. 3; $170-$300, with dinner packages starting at $395
2014-15 season continues through June 27, 2015
Tickets per program: $15-$163; 415-864-6000, www.sfsymphony.org
Where: Davies Symphony Hall, San Francisco