Classical Safri Duo; Mullova and Anderszewski City of London Festival

Percussion has come a long way since James Blades, Britten's favourite player, used to demonstrate his Chinese gongs on black-and-white TV. Even so, and the Danish Safri Duo are the first to say it as one of their platform anecdotes, the problem remains the age of their repertoire. It contains nothing serious from earlier than the Sixties: the 1960s. There is a beautiful melodic instrument, the marimba, that is the mainstay not only of their own ensemble but also of Evelyn Glennie's groundbreaking act. But there's nothing to play on it except arrangements.

Well, arrangements were often good enough for Bach and Liszt. And the need for new repertoire has sparked off another wave of the arranging game, at least for this pair of consummate young musicians. Amid the opulence of London's Guildhall last Thursday, they began their City of London Festival recital by hypnotising their audience with a two-marimba version of Bach's Prelude from the 2nd English Suite, shocking them with Mendelssohn's F minor Fugue, then soothing them again with three Bach preludes and Well- tempered Percussion, arranged by Per Norgard. Reich's Clapping Music gave scope for their rhythmic virtuosity, untramelled by harmony or tune - the audience joined in for the easy bits. Their reward was Alborada del gracioso, reworked from the piano original in a way of which Ravel, himself a master arranger, would have been proud.

Of the post-1960 music, Jacob ter Veldhuis's percussion showcase, Goldrush, seemed too predictable to last. The tough modernism of Rolf Wallin's aptly titled Twine sounded more durable. Minoru Mike's Marimba Spiritual II embodied the "anything you can do" approach. Though its sizzling complexity made a sure-fire ending to the concert, it will surely inspire other composers to come up with bravura pieces that are even more difficult.

While Safri lightened the load with a sense of comedy in their spoken introductions to each piece, the violin-and-piano team of Viktoria Mullova and Piotr Anderszewski in the Drapers' Hall on Monday kept up a serious demeanour that refused to soften, even in the riotous encore number, The Banjo and the Fiddle. Mullova plays the violin with awesome control of pitch and articulation, but transmits few signals that give evidence of emotional involvements. Anderszewski is the opposite, warm and expressive, shaping the sound as if it were some plastic substance arising through contact between keyboard and fingertips.

Janacek's Violin Sonata was a perfect opener for this balance of opposites, fire and ice mingling in music that demands both qualities to master its impulsive flow. Webern's Four Pieces, Op7, proved even more suited to the artists' style: muted violin made riddles with veiled, bell-like chords, cleansed through Anderszewski's touch into an intense purity of sound.

It was in the classical items, Beethoven's "Spring" Sonata especially, that the team pulled in opposite directions. In the scherzo, among the composer's most witty, the violin never got the joke, despite the piano's prompting. There was more agreement in Brahms's radiant Second Sonata and, in the flowing finale, even a welcome tone of relaxed intimacy.