It is nothing short of staggering to see how Carsen, using only light and shade, manages to create new spaces again and again within this dreadful labyrinth of steel. Fabio Luisi conducts the Vienna Symphony Orchestra as though in a beguiling dream. Every single instrumental ornament, no matter how small, is clearly audible on the evening air. The ensemble, freed from the obligation to produce great volume in sound, can now concentrate entirely on beauty of tone and expression.