LENOX -- Backstage, Andris Nelsons presented a different picture than Andris Nelsons onstage.
In his opening concerts last weekend, the Boston Symphony's incoming music director was dynamic and full of bold ideas about the music. In an interview a few days before, he was talkative in sometimes halting English, but guarded about his plans for Tanglewood and his role in it.
He spoke in broad generalities about possibilities: programming to take advantage of the open-air Shed; maybe working with Tanglewood students; maybe a role for opera; a need to develop music education in the schools -- likewise, a need to bring in both younger and older audiences.
But these, as the great Donald Rumsfeld once said, are known knowns. The real question is what will he do about these challenges.
Specific questions are and were:
n How long will his summers in residence be after the three weeks in 2015?
n What role will he play in the coaching and mentoring of students?
n What kind of programming will attract those new audiences?
n How much emphasis will he gave to new music? To opera?
Each question was answered with generalities.
In good measure, the reticence was understandable. This is Nelsons' first visit as director-designate, and he is here to observe and learn - to "brainstorm," as he repeatedly put it. And he spoke in an interview, a controlled environment in which the subject reveals only as much as he wishes to reveal.
"Everybody is at the top level, so it's such a great experience," says Harrison Dilthey, 18, a bassist from North Adams, of his participation in the National Youth Orchestra of the USA. It is one of two ensembles that will make back-to-back Tanglewood debuts next week in Ozawa Hall.
First, the New York collective The Knights will play an eclectic program on Wednesday night with soprano Dawn Upshaw and trumpeter Hakan Hardenberger as soloists.
The youth group, 120 strong, comes under the aegis of Carnegie Hall's educational program. It is embarking on its second summer, with Tanglewood the second stop on an eight-concert cross-country tour. The all-expenses-paid members come from 35 states, Washington and Puerto Rico. Valery Gergiev conducted last year.
The tour program consists of a new work by Samuel Adams, Bernstein's Symphonic Dances from "West Side Story," Britten's Violin Concerto and the Mussorgsky / Ravel "Pictures at an Exhibition."
"For me," said Robertson, "having played in an orchestra, you want repertoire that is both wonderful for the public but also it's really juicy and great to play." In addition to that, Shaham will be a soloist young players "can look up to as a mentor," he added.
The age range of the orchestra, 16 to 19, touches on with the ranges of the high school-aged Boston University Tanglewood Institute orchestra and the fellowship Tanglewood Music Center Orchestra. Robertson said that because of the stringent touring schedule, there probably will be no chance to interact with the Tanglewood ensembles.
Dilthey is a former member of the Berkshire Symphony and Boston Youth Symphony. He heard about the national orchestra while a student last summer at the B.U. institute.
"Hey, that's kind of a cool opportunity," he recalls thinking.
A 2014 graduate of Mount Greylock Regional High School, he will continue his bass studies in the fall at Ithaca College and hopes someday to play in the Metropolitan Opera Orchestra.
Knights co-director Colin Jacobsen describes his group's first Tanglewood visit as both a debut and a homecoming.
That is, several members are former TMC fellows and several are players in Yo-Yo Ma's Silk Road Ensemble, which began life at Tanglewood in 2000 and has returned for workshop sessions several times since.
The collective numbers about 40 members in all but appears in various groupings according to the program. About 25 members will appear at Tanglewood.
The program is all 20th- or 21st-century but ranges afar, from Ligeti's "Old Hungarian Ballroom Dances" to Stravinsky's "Dumbarton Oaks" Concerto and Maria Schneider's triple Grammy Award-winning "Winter Morning Walks" for soprano, jazz players and strings. Hakan Hardenberger will be the soloist in transcriptions of songs by Joni Mitchell, Kurt Weill and others.
The ensemble grew out of informal chamber music sessions in the New York apartment of brothers, co-founders and co-directors Eric Jacobsen (cellist and conductor) and Colin Jacobsen (violinist and composer). They formalized the band of friends as The Knights in 1999.
Ma and Upshaw were models.
"Both Yo-Yo and Dawn Upshaw are musicians that we in The Knights all grew up admiring for their spirit of curiosity and constant experimentation and seeing classical music as having porous borders," Colin Jacobsen said.
Friends of friends recommended the brothers and other Knights members to Ma for the Silk Road Ensemble.
"There's a deep connection between the Silk Road Ensemble, The Knights and Tanglewood," Jacobsen said.