Planet Tree Music Festival | The Round Chapel, London

Even with better promotion and some more familiar composers than before, audiences for this year's Planet Tree Music Festival have generally, it appears, been small. A variety of venues adds flavour to the proceedings but makes the individual programmes, strung out over three weekends, seem even more unconnected.

Even with better promotion and some more familiar composers than before, audiences for this year's Planet Tree Music Festival have generally, it appears, been small. A variety of venues adds flavour to the proceedings but makes the individual programmes, strung out over three weekends, seem even more unconnected.

The fourth festival ended with a marathon from Piano Circus. Eight hours of minimalism in Hackney from six electric keyboards is not everyone's idea of a good Sunday out, and audiences never rose above the 60 or so who went to the imposing Victorian Round Chapel for the main evening concert. They'll have heard a snatch of David Stevens' electronic sound interludes, which peppered the day's activities. A snatch was probably enough.

They missed the vacuous vamping, purportedly inspired by the 12th-century composer Pérotin, of Regimentas Petronis's Reminiscences. But at least the 40 minutes of this saw the Round Chapel acquire a real aura as darkness fell, and Dave Snowdon's often stimulating and beautiful computer graphics and some well-considered lighting effects took hold. (Blue fluorescent tubes and the red of electric fires created a purple haze as the combination magically lit up the church windows.) There was also a lively and thoughtful performance of Piano Circus's original inspiration, Steve Reich's Six Pianos.

In the evening, the London premiere of Erkki Sven-Tuur's Transmission revisited 1960s Ligeti with surprisingly individual results. Three British works were brand new. Martyn Harry's quirky takes on minimalism and allied trades move from strength to strength, and his Digging Deeper mixes somewhat Romantic gestures and a high dissonance level with the aid of some imaginative counterpoint. The festival director Lawrence Ball's own Gong Piano No 8 gradually energises a slow procession of dirty chords until, all too soon, it transforms into a final "firmament of harmonic implosions", as he calls it. Patrick Nunn's 21st-Century Junkie proved to be just ephemeral junk.

Though the combination of sometimes rather raw piano sound and the church acoustic didn't suit everything on the programme, the ensuing "classics" by Conlon Nancarrow and Terry Riley were capably handled.

But what to say about the 77-year-old French mystic recluse Jean Catoire and his Symphony No 41, Op 280, which in this arrangement by Richard Harris took more than an hour? Its endless, meandering sequences of triads in the upper half of the pitch spectrum were sometimes totally predictable. Yet the occasional intrusions of other material - scrunchy dissonances and hesitant single notes - were so incomprehensibly anachronistic that I really wasn't sure whether they were Catoire's own or untypical errors by players probably by now half-asleep.

Whatever, the results struck me as bafflingly, enervatingly pointless. The only fun to be had was when a mouse played around our feet in the hushed church: confident, presumably, that all sentient human activity there had, for the moment, ceased.