CLASSICAL MUSIC / Platform 2: Ixion Ensemble and George W Welch - ICA, London SW1

The most arresting image of Wednesday's Platform 2 at the ICA was from Rene Clair's 1920s Surrealist film classic, Entr'acte: Erik Satie and Francis Picabia loading a cannon on a Paris rooftop. The most arresting music was the serene string harmonics closing Andrew Toovey's Shining Forth, played in the Ixion Ensemble's early-evening recital, celebrating the seventieth birthday of Iannis Xenakis and the eightieth of John Cage.

As it was, day three of the festival had a Surrealist shape overall: firstly, works concentrating on the innate possibilities of musical tone; then a late showing of Dada cinema. To the slinky tunes of accompanying ensemble George W Welch, Hans Richter's Ghosts before Breakfast and Joseph Cornell's Rose Hobart cut, transposed and reversed their texts in pioneering studies of the mechanical manipulation of film. Using the title of a former Underground station, British Museum, a variation sequence by Ian Gardiner mused gently on current news events projected on-screen, before a savage quotation from Stravinsky's Rite of Spring leapt out of the music like a dinosaur loose on the Central Line.

If the Ixion composers, renouncing such referential effects, had a shared quality, it was to burn with a pure fire. Charles Mutter (violin), Zoe Martlew (cello) and Ben Morison (piano) caught this quality in the intensity and dedication of their playing, both in the Toovey and in Michael Finnissy's In Stiller Nacht. Finnissy himself was soloist in Xenakis's virtuosic Hermes. Not many pianists deliver such passionate conviction in their performance. Not many composers write like this either.