After a leisurely dinner at one of the picnic tables on the grounds, my friend Kit and I took our seats in the Shed to hear the BSO led by their music director, Andris Nelsons, in his one-and-only Tanglewood appearance this season. Nelsons, who recently quit the new Bayreuth production of Parsifal in a huff, apparently chose to take a family beach vacation over extending his stay in the Berkshires. Which, combined with his recent appointment as the next Kappellmeister (director) of the Leipzig Gewandhaus Orchestra - a position he will hold concurrently with Boston - doesn't help to dispel the notion that Nelson may not be as invested in Boston as past music directors.

But, from all accounts, the BSO savors their relationship with the 37 year old Latvian who, despite his relative youth, is unquestionably one of the hottest conductors in the world today. At the time of his appointment in 2013, BSO Concertmaster Malcolm Lowe was quoted as saying:

"It is clear that the joy and love of music is at the heart of Maestro Nelsons' music making. His musical center, knowledge, and artistically searching human spirit, along with his youthful exuberance, will inspire our future."

The concert began with Biss performing Mozart's Piano Concerto No. 27 which, for Mozart at least, sounds both delicate and difficult, serene and strange. Biss seemed a bit nervous and on-edge, but generally held up his end of the bargain. But, in the end, this performance wasn't anything special. Blame Mozart, blame the performers, but music, even when played outdoors, should reach out and grab you by the back of the neck. 

Which is exactly how I felt on the second half of the program, when Nelsons led the BSO in Mahler's 9th Symphony. Addressing he audience beforehand, Nelsons said that this symphony had deep meaning for him, as it was the piece with which he made his surprise debut with the BSO back in 2011 at Carnegie Hall. 

"I have a very intimate feeling with this piece," he said in heavily accented English, "playing with BSO. I am happy to see such large crowd tonight. Makes us feel bigger."

Nelsons seems to have matured in his interpretation of this last of Mahler's completed symphonies (Mahler left a 10th unfinished at his death), allowing the winds and brass to properly blend with the strings. Throughout the nearly 90 minute performance, Nelsons seemed in complete command of the score, especially the 3rd movement (Rondo-burleske), which he conducted with militaristic verve. 

But it is the powerful, transcendent Adagio that is the ultimate judge of performances of Mahler's 9th, and here the BSO was nothing short of extraordinary. The orchestra articulated every phrase and accent. At the end, Nelsons dropped the strings down to a nearly imperceptible quiet: it was like watching someone slowly fade away, struggling for one last gasp of life. It seems impossible that this mystical music of farewell could be so well understood by someone not yet middle-aged, but I and everyone around me was spellbound.

I missed Saturday night's concert of Nelsons and the BSO performing the Sibelius Violin Concerto (with Augustin Hadelich) and Beethoven's 7th symphony (more about that later), but was back at Tanglewood on Sunday afternoon to hear Nelsons conduct the young fellows of the TMC Orchestra in an all-Brahms concert in the Shed. This time, Lewis was the pitch-perfect soloist in Brahms' Piano Concerto No. 1: a surprisingly dark and intense work Brahms completed when he was only 25, after having worked on it for more than four years.

Brahms took even longer to complete hist 1st symphony, laboring on it for more than twenty years before its eventual premiere in 1876. Despite - or perhaps because of - the long gestation, it is regarded as an unquestioned masterpiece, having been performed regularly by the BSO since their very first season in 1881, as well as their first Tanglewood season in 1937. Under Nelsons, the fellows of the TMC Orchestra sounded completely assured, drawing out every note: particularly in the C major finale, which sounded grand and majestic, like watching the sun rise over the mountains. The final fanfare still gives me tingles. 

But for me, the absolute highlight of the weekend was Saturday afternoon's performance of Mahler's Symphony No. 6 in Ozawa Hall. This time, it wasn't the BSO or even the TMC Orchestra, but a concert by the Boston University Tanglewood Institute (BUTI) Young Artists Orchestra: a summer program for high school students who have not yet begun college or conservatory training. BUTI, which celebrates its 50th season this year, benefits from its proximity to Tanglewood, offering masterclasses with many of the same conductors, soloists and BSO members that mentor the older TMC fellows.

Led by the journeyman young American conductor Paul Haas, this performance of Mahler 6 was far from perfect. But, what these kids lacked in precision, they more than made up for with youthful passion, letting the music carry them to multiple moments of brilliance. Sitting in the balcony behind the stage, I had a bird's eye view of the proceedings as Haas coaxed the players to dig deep - particularly in the half-hour long finale, with its explosions of brass and three shattering hammer blows. This is serious, complex music that would be a challenge for any orchestra, much less a group of high schoolers. Credit Haas and the BUTI faculty for whatever they did to give these kids the skills and confidence to pull it off. Anyone who thinks classical music is dead or dying needs to make their way to the Berkshires before the summer's out. (The remaining BUTI concert schedule is listed here.)

More pics on the photo page:

• Friday Prelude Concert
• Friday BSO Concert
• Saturday BUTI Young Artists Orchestra Concert
• Sunday TMC Orchestra Concert