Baldur Bronnimann sandwiches himself between two performances of Ligeti's Kammerkonzert and attempts to explain some of the intricacies of this twentieth-century masterpiece to the audience. Part of his explanation involves demonstrating the differences between what he refers to as Ligeti's "exactly determined chaos" on the one hand, and simple musical chaos on the other, both of which the ensemble perform obligingly on cue. Bronnimann urges us to hear the clear-cut precision of the Hungarian composer's network of frantic musical events as estranged from the more superficial perception of them as just a series of random noises.

And from this display, we become aware of some remarkable effects. Firstly, Bronnimann acknowledges the potentially alienating sound of Ligeti's work, a work that appears self-obsessed and introverted, and he encourages the audience to understand their own listening strategies in the face of such difficult sounds. Secondly, as a consequence of this informative half-time interlude, we realise that what binds this work together, what produces, its formal integration is the fundamental way in which Ligeti uses the idea of phrasing to generate and disrupt musical coherence.

This was an extremely bounded and controlled performance from the NYOS players, in collaboration with the BBC SSO, of Ligeti's virtuosic and unforgiving concerto. At times claustrophobic, this is a work that continually suspends itself over an abyss between extremes; it is both fluid and angular, melancholy and robotic. And this complex set of opposing musical aspects was handled tremendously by the entire ensemble.