Prom 57: Zimmerman/Gustav Mahler/Gatti, Royal Albert Hall Proms Chamber Music 7: Schafer/Nash/Brabbins, Cadogan Hall, London

Alban Berg’s Violin Concerto is full of codes.

Some were secret, like the number symbolism for an adulterous affair, and the Carinthian folk melody representing the peasant girl by whom he had an illegitimate daughter. But the main message was blazingly up-front. He wrote the work as a requiem for Manon Gropius – daughter of Alma Mahler and the architect Walter Gropius - whose death of polio at 18 had shocked him deeply. The first movement depicts her in life and health, and the second in sickness and death; Berg’s manuscript is annotated with ‘cries’ and ‘groans’ of instrumental grief. And he made the solo instrument the symbol of his protagonist, whose soul it enshrined. Dying soon after he finished it, he had also thus written his own requiem.

Frank Peter Zimmerman was the soloist here, bringing a singing tenderness to the dreamlike opening: this is intellectually-organised tone-row music, but he gave it a naturalness which came from the gut. There is a winning modesty in this German player’s virtuosity, and though his voice was powerfully threaded through everything, all you registered was his relaxed control, and the unfailing beauty of his line. With its elaborated Bach chorale and the now-distant Carinthian tune, this work finally resolves into ecstatic acceptance, and Zimmerman’s violin became the visionary preacher, with the orchestra becoming his congregation.

And what an orchestra. The Gustav Mahler Jugendorchester may all be under 26, but in a season when we’re getting the best bands the world can offer, this one - conducted by Daniele Gatti - was right up there too. They may have been a shade too cautious for the full glitter and swagger of Strauss’s ‘Rosenkavalier’ suite, but their account of Wagner’s ‘Parsifal’ prelude had wonderful poise, and they despatched Ravel’s ‘La valse’ with a suaveness turning to savagery.

In Chamber Prom 7, Debussy’s ‘Sonata for flute, viola, and harp’ was elegantly delivered by Philippa Davies, Andriy Vitovych, and Lucy Wakeford, after which Christine Schafer reprised - under Martyn Brabbins’s direction - a role she has made her own in Schoenberg’s ‘Pierrot Lunaire’, with two additional members of the Nash Ensemble. This was a predictably brilliant performance, with the mercuriality of Schafer’s Schprechgesang matched by the virtuosity of the ensemble. This work’s extraordinary blend of Gothic Orientalism exuded a luscious abandon.