Masur injured his shoulder when he fell off a stage in Paris in April. He had to be helped to the podium on Saturday night for the opening concert in the vast turbine hall of a former power station that served the Nazi rocket program on the Baltic Sea island during World War Two.

Summoning up some of the vigour that made him a leading dissident as a young man in then-communist East German, Masur - startling the packed first-night crowd - in mid-concert shouted out "one" to the orchestra, to get the players back on beat.

In keeping with the history of the locale, Masur also made certain all of the piece's dark details, especially a kettle-drum roll that sounds like artillery fire, and which he forced the percussionist to perform a half dozen times in rehearsal, came through in the energetic playing of the youthful ensemble.

"If you love music and you like to listen to music you can be helped by music but if you have nothing of that you have a problem," Masur told Reuters before the concert, when asked how he found the energy to carry on.

The festival, in its 19th season, brings a high level of music-making to the island, a popular tourist destination during the summer months. This year's festival, which runs until Oct 7, explores relationships between German and Russian music and also featured master classes with Masur for seven young conductors.

"He really imparts knowledge no one else could give us," Gemma New, 25, of Wellington, New Zealand, the only woman conductor among the seven, said.

Masur, who lived much of his life in communist East Germany and helped to mitigate violence during its turbulent collapse before going on to a distinguished career in the West as music director of the New York Philharmonic, and later as principal conductor of the London Philharmonic Orchestra, said not everything had changed for the better with communism's demise.

"I get a cultural shock because then I only feel that nobody of you really understands what it meant in a socialist country," he said when asked about the aftermath of the end of communism. "In East Germany everybody had work and money, not very rich but fine, good enough. And I think we have to face the fact that not everybody who's free is happy."

As for why, at his age and in frail health, he keeps up a strenuous conducting schedule, leading the youth orchestra and holding master classes for younger conductors, Masur said he feels it is part of his calling to help the next generation.

"I don't like them to be hopeless and lost because normally they get a good education, then they get out and they get no position or they are just suffering to get a position in a good orchestra and then what should they do? They try to get money in any way and then for me the problem is how will the future look?"

HUGELY APPRECIATIVE

The musicians, but especially the young conductors, were hugely appreciative of his efforts.

Kah Chun Wong, 25, of Singapore, said Masur had instilled in him "a religious passion for music", and he was moved by his "relentless energy to deliver what the composer wants, even when he's 85".

Johannes Zurl, 32, of Germany, said Masur had impressed upon him "the simplicity of conducting".

"Sure, he's an older guy and he's not jumping around, but I am extremely inspired to make an effort to bring out more with less," he said.

The young conductors took turns leading sections of the opening piece, Mussorgsky's "Pictures at an Exhibition", and were enthusiastically applauded for their round-robin effort.

Of course, with an orchestra of more than 90 young people, there was more on the agenda than just making music.

"The main thing for me is the people that you meet," said Jason Denner, 27, a San Diego clarinetist now based in Berlin.

"It's in one sense the connections for work, but also you meet some really pretty cool musicians. For a long time this orchestra has attracted the type of person who is willing to take a lot of risks and wants to do things a little bit differently and doesn't necessarily want to be first chair in the Berlin Philharmonic."

Festival director Thomas Hummel said the event has been growing in importance year by year and now had visitors from as far away as the United States, though most of the audience comes from Germany, Poland, the Netherlands and Switzerland.

"Not many islands have a festival like this," he said.

Having Masur conduct was a draw, but it had its downside, at least for those sitting in the back rows of the orchestra, which was founded in 2008 by the festival and Baltic gas pipeline company Nord Stream AG.

"For me he gives us the impulses but not much more," bass trombonist Ingrid Utne, of Stavanger, Norway, said. "I think there would be more in it for me if I could hear what he's saying all the time."

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