Success in Beijing is not the easy mark that it once was. Competition is more formidable. The Boston Symphony has recently visited. And next door to the Philadelphians' concert, at the National Centre of the Performing Arts Opera House, Verdi's Il Trovatore was raging away to a capacity audience with lavish sets, computer-generated graphics, and a charismatic - and predominantly Chinese - cast.
As suggested by the enthusiastic yet less than uproarious response to Thursday night's Tchaikovsky Symphony No. 6, a warm bath of Philadelphia sound remains welcome but no longer a panacea. And in a sign of increasing sophistication on Friday, the audience did not need a full dose of that sound to know that Mozart's fleet and slimmer Symphony No. 41 was a special performance in its own way: robust but elegant, vital but clear.
Always in the mind-melding business, the orchestra has found itself doing so across generations, nationalities, and abilities, some efforts with more success than others.
Before leaving Beijing, percussionist Chris Deviney traveled to the city's outskirts for a master class with a somewhat less-than-classical ensemble: the People's Liberation Army Band.
About 200 band members and their students live on a Mao-era campus that has seen better days. In a room with curtains closed against the Friday afternoon heat, percussionists old and young listened attentively, but were strangely shy about playing for Deviney. When one marimba player volunteered, he was so good the others might have lost face had they followed him.
"I didn't get a sense of how many were studying percussion on the broadest sense or how many were there just to do a job," Deviney said. "But I still think the master class was worth doing. Like any job, nobody wants to go to work and punch a clock. They're looking for outlets to express themselves musically."
The Philadelphians - hornist Denise Tryon was also there - were warmly rewarded with a lavish luncheon in a campus dining room resembling a 1960s-era Ramada Inn and hung with huge photos of massive Tiananmen Square rallies, where the People's Liberation Army Band has been in its element.
Weather-related travel delays to Shanghai on Saturday meant that musicians went straight from the airport to some of the tour's less conventional appearances.
Six string players found themselves in a pop-music venue playing the Brahms Sextet No. 2 while a video screen behind them flashed their photos and biographies. The occasion was "A Night With Xuri," a variety program bringing together artists featured by the Xin Hui company, which is streaming the Philadelphia Orchestra's Sunday concert. Here the culture gap was apparent: The concert ended with the Philadelphians, the traditional-instrument Oriental Angels, and crossover singer Jia Ruhan all performing "Rose Rose," a hit in 1930s Shanghai whose history and significance are bound to be lost on Westerners.
Far more rewarding was a reengagement of students and musicians at the Angel Salon, a special Saturday-only music school for autistic children. Cameras from China Central Television, which is making a documentary about the school, awaited them.
In the corner, a lanky teenager at the piano had seized on a portion of a Chopin piece, playing it over and over while orchestra hornist Jeff Lang and recently appointed trumpeter Tony Prisk set up an array of primitive and modern wind instruments, from hunting horns to conch shells.
Other students practiced their horns and roughhoused in the humid space inside the Shanghai Huangpu Teenager Science and Technology Activity Center. The room was utterly without affectation and bursting with exuberance. At one point, two players launched into a high-energy duet, switching between piano and marimba, tag-team style, with equal proficiency.
"I don't play that many instruments!" said Nézet-Séguin, who had arrived a bit late.
"They seemed to have found a voice," Lang said. "They can relate to an audience in a way that they can't with the written word or the spoken language."
He showed a horn player an improved hand position. Prisk showed a trumpeter a better way to breathe. Both students caught on quickly and used the improvements throughout the day. "You don't want to say something to them that might steal their joy," Prisk said. "But you can actually make the improvements."
A brass quintet lined up across the room and reprised its own version of "Amazing Grace"; with Nézet-Séguin conducting it was markedly more focused. The theory that music finds a clear pathway to autistic children was a fact Saturday.
"Music is the most important thing in our lives," the Philadelphia conductor told the students through an interpreter, "and I can see that it's the most important thing in yours."
The Philadelphia Orchestra's Mozart/Mahler concert will be video-streamed live from Shanghai at 7:30 Sunday morning. Preregister at www.yunbomedia.com.