CLASSICAL MUSIC Houston Symphony Orchestra / Christoph Eschenbach Barbican, London

It's disturbing to think that, for one or two people, Saturday's Barbican concert, given by the Houston Symphony as part of the centre's hallmark Great Orchestras of the World series, might have been a rather blue affair. Blue-grey flecked with steel, to be exact - apparently some of the hues aroused by the key of E flat major in the minds of those gifted with synaesthesia, the power to hear music in terms not only of sound but also of colour.

For the programme consisted of two works in that solid, heroic key: Beethoven's Fifth Piano Concerto, the "Emperor", and Bruckner's Fourth Symphony, the "Romantic". Both, of course, are romantic without a trace of blue in any modern sense. Yet whether or not the key could be heard in the mind's eye, the feel of an evening locked into one tonality was unavoidable. The orchestra clearly intended that the ear was not to be tickled. Indeed, they were scaling the heights, their aim to master nothing less than the grandly monumental.

That they got there was due both to the collective skill of the players and to the wisdom of their music director of nine years' standing, Christoph Eschenbach. He is one of those notable pianists who in later life has turned to the podium as a flourishing second career, and he brought purpose and clarity to the evening as a whole, and insights into the conducting of the concerto in particular. Having chosen the programme, he knew the hazards of its long-term strategy. Though grandly meted out, the first movement of Beethoven's concerto launches a plethora of vivid ideas with such rapidity that nothing less than a thoughtful reading can maintain the balance of the whole. Unless firmly controlled, its latent disunity might with hindsight sound even more blatant in contrast with Bruckner's lofty periods; their generous phrases, in turn, felt rather more prolix than usual.

In the event, there was no sense of either work being caught in the rebound of the other. Mitsuko Uchida, a pianist whose delicate temperament shuns the rhetorical, was clearly in harmony with Eschenbach's intentions. Her respect for detail underpinned the long middle section and cadenza of the first movement. In the second, her luminous tone in the upper keyboard register chimed well with chords on flute and clarinet. Nowhere in her reading did the form draw attention to itself except, for the purpose of comedy, in the finale's Landler-style episode, introduced by a tipsy bassoon. Elsewhere, the composer's remit of exaggeration was left firmly where it belonged: in the score.

Whatever the imagined colour of Bruckner's Fourth Symphony, the lasting impression on this occasion was of golden brass. The Houston trumpets and trombones relished the task of delivering Bruckner's grand chorales, their slow release of energy finely judged by Eschenbach. He took a stern view of the opening melody, but his grasp on dynamic flow was admirable throughout. There were also moments of lyrical beauty; the clarinet melody of the first trio section was memorably delivered.