MUSIC / Family values: Nicholas Williams spends a weekend of contrasts at the Brighton Festival

Berlioz described his Romeo et Juliette as a symphony with choruses. Even so, the genre is flexible. On disc, it can have symphonic pace and resolution. Heard live, it gains operatic flair but shows its seams as well.

Saturday's semi-staged account at the Brighton Festival was no exception. With the Capulet revellers an echo from the back of the hall, and the Brighton Festival Chorus in black for the funeral cortege, there was as much atmosphere and theatrical detail as the Dome allows. Even so, there were problems of concentration, not just in the many pauses punctuating the three scenes, but in the nature of the music.

The prologue, sung by the mezzo Martine Mahe and tenor Leonard Pezzino in heroic form, gave the bones of Shakespeare's story. Thereafter, it was an hour-long parade of striking tone-pictures: from Scene 2's Queen Mab scherzo, to the passion of the balcony and Romeo's horror at the tomb.

However, these were pageants rather than actions. And the spaces in between - the lively transitions of a classical symphony - are in Berlioz the weak links in the chain. Mark Elder's was a lively reading; but he wanted more than the Orchestre National de Lille could deliver. In the set-pieces, they were adequate. Elsewhere, the strings lacked the depth to carry through the composer's weaker moments. Though the oboe and bassoon solos had a pleasing astringency, the woodwind failed to blend.

On Sunday, the Smith Quartet in the Pavilion Music Room took the festival theme of the family another way, exploring the younger generation of minimalists. They gave the premiere of Carl Vine's Third String Quartet, with Nyman's Quartet No 2, Fitkin's Servant and Martland's Patrol.

Most imposing and sombre was the Martland, whose hushed canons and frenzied contrasts of extreme tempos within one texture mapped out an expressive landscape of their own. More jovial, the Fitkin showed an artless sophistication in playing fast- and-slow rhythmic games with a handful of chords.

As much as Reich and Andriessen, Bach seemed to be the true progenitor of these pieces; not just in their polyphony, but also in the objectivity of their moods. There was a subtle Baroque flavour in the Vine, too, with a slow movement of ravishing arabesques above a pizzicato cello, balanced by outer sections of darting counterpoint.

In his quartet, a dance score written for Shobana Jeyasingh, Nyman used time- cycles from Indian music in each of the six movements, but with his own characteristic cut-offs and wild climaxes. He mentioned Cage's influence, but a performance of the American's String Quartet in Four Parts, given on Saturday by the Cambridge New Music Players, was neutral-toned. In these abstract pictures of the seasons, one's feelings flowed into the musical gaps. A far cry from Nyman's forcefulness - and from Berlioz.