Listening to Christoph Eschenbach conduct can, on occasion, be a bit like trying to swim upstream in a river of molten chocolate. Beauty rather than truth is ultimately what he's about, and his two London concerts with the Philadelphia Orchestra, of which he became music director last year, revealed both the quintessence of his style and its limitations. He lingered, with his usual fondness, over every textural detail: everything was gorgeous to the point of satiety.

When you make beauty an end in itself, however, you can come close to robbing a work of its range and meaning, which was very much the case here. Schoenberg's Verklärte Nacht was a mix of rapture and stodge that only intermittently touched on the work's deeper, psycho-dramatic implications. The opening of Mahler's First Symphony was genuinely magical. Later on, however, Eschenbach shaded the bitter humour and the delirious jolts towards traditional Jewish music towards a unity of tone, rather than presenting them as garish contrarieties.

Things improved in the second concert, Brahms's Violin Concerto. Gil Shaham was the soloist, setting the pace and mood throughout, so that Eschenbach, once past a portentous account of the opening orchestral section, was forced to change tack to follow him. The result was very worthwhile.

Shostakovich's Tenth Symphony followed, hampered by Eschenbach's inability to deal with the score's multiple layers of irony and its indictment of the closing years of Stalin's regime. Rarely, I suspect, has the symphony sounded both so exquisite and so utterly lacking in terror.