Trondheim Chamber Music Festival, Trondheim, Norway

You might not imagine that Trondheim, nestling within a fjord on the north-west coast of Norway, has an awful lot in common with Vienna. But there is at least one thing: an unusually high proportion of the population seems to walk around with cellos strapped to their backs, violins under their arms, or horns slung over their shoulders. Trondheim appears to be a surprisingly musical place.

You might not imagine that Trondheim, nestling within a fjord on the north-west coast of Norway, has an awful lot in common with Vienna. But there is at least one thing: an unusually high proportion of the population seems to walk around with cellos strapped to their backs, violins under their arms, or horns slung over their shoulders. Trondheim appears to be a surprisingly musical place.

It might simply be that the annual chamber-music festival, now in its seventh year, draws them out in higher quantity, but the evidence of the concerts themselves – they display an unusual degree both of involvement by the local music-education institutions and of audience enthusiasm – argues against such an assumption. And the festival both feeds on and nourishes that involvement: its visiting artists strut their own stuff, of course, but they also coach Trondheim music students, some of them barely in their teens, and musicians from further afield – this year chiefly Russia and Poland.

It's cleverly organised: young ensembles – string quartets and piano trios – are chosen to join the festival's "Academy" for coaching by the professionals. The best of that lot then go forward to a competition, which includes a work commissioned from a prominent Norwegian composer for the occasion; victory brings the promise of engagements across Europe. But even the groups that get knocked out come away with a consolation prize, in the form of bookings for concerts in far-flung Norwegian communities that don't normally hear any live music.

Provincial audiences are notoriously conservative, but with a composer-in-residence (a Norwegian and an international figure, year about), the Trondheim festival ensures a healthy admixture of contemporary music in the diet. This year, the eminence was Luciano Berio, whose Sequenzas for solo instruments were lettered through the week as through a stick of rock, with an orchestral concert midway. Most touchingly, he listened as the children of the local Saturday-morning music-schools played his 34 violin duos.

The imported stars assisting a panoply of Norwegian talent were two Swedes – the trombonist Christian Lindberg, whose account of Berio's Solo almost beggared belief, and the cellist Frans Helmerson – and the Nash Ensemble, which is such a regular feature of British musical life that one tends to forget what towering performances they can give.

And Trondheim has cracked a problem that the rest of classical music has yet to face up to: half the faces in the audience are well under 20, some of them quite obviously still at school. What can we learn from them to help readjust the age-cohorts in our own concert halls?