BBC SO/Belohlavek, Barbican, London

It is more than a year until Jiri Belohlavek becomes chief conductor of the BBC Symphony Orchestra, and only a month since he was awarded the job.

It is more than a year until Jiri Belohlavek becomes chief conductor of the BBC Symphony Orchestra, and only a month since he was awarded the job. This week's appearance was dead on cue for questions about what the future may promise. "Lots of Martinu" appears to be one of the answers, though whether that's a promise or a threat is a question of taste.

For some, Martinu composed too much for his own good. There's a hint of laziness about linking a prolific output with a lack of self-criticism, as though it lets you off bothering to listen for yourself. Sure enough, when one of his pieces crops up, the mix of heady melody and driving energy usually delivers a positive experience. It could just be that the difficulty of choosing between a large number of strong works is what has kept this mid-20th-century Czech exile out of performers' repertoires. Belohlavek slipped in two of them, and apparently surprised a large audience drawn by the Mozart Requiem that shared the concert.

Certainly, there's nothing mass-produced about Martinu's Fantaisies symphoniques, the last of his six symphonies. Even by his own standards, the music is uniquely freewheeling. It is like an increasingly desperate search for repose, and it subjects its outbursts of lyrical ecstasy to extreme mood swings. There are moments of brilliant, swirling colour that share the imaginative world of Martinu's opera Julietta, and an interlude of hopeless longing like a throwback to Dvorak. But all the time, the search is disrupted by long, grim rampages that eventually run right off the rails.

In contrast, the Memorial to Lidice, which opened the concert, is a compact expression of a single mood. It commemorates an atrocity perpetrated in 1942 by German invaders, and stretches out Martinu's typical shifting harmonies into monumental blocks of sound, finally puncturing the grief with a defiant blast of the V-for-victory motif from Beethoven's Fifth Symphony. Its performance set the evening on a course of serious, concentrated, emotionally charged music-making, steadily paced, full-toned and firmly held together. All very Central European in feeling, this suggests that the orchestra's future is likely to sound, in the best sense, "traditional", in a way that it hasn't since the time of Rudolf Kempe.

The Mozart Requiem inspired more of the same. Although the orchestra was reduced by half, the basis of the singing was the very substantial BBC Symphony Chorus. Warmth and breadth prevailed over high drama, subtly accented and finely balanced. The soloists were a contrasted quartet of up-and-coming singers. Kate Royal's suave soprano and the intense tenor of Robert Murray tended to catch the attention, perhaps inevitably given the nature of Mozart's writing for them, but they did not overshadow the musicianly eloquence of the mezzo Karen Cargill and the secure bass of Matthew Rose.