Proms; BBC SYMPHONY ORCHESTRA / PETER EoTVoS; Royal Albert Hall, London & Radio 3

First impressions of Monday's Prom suggested more people on stage than in the stalls. And certainly Peter Eotvos's Psychokosmos calls for a crowded orchestral gathering with generous strings fanning front-placed woodwinds, brass and percussion. The piece itself, a sort of backward glance at an earlier work inspired by the "big bang" theory, has a lone cimbalom goad her colleagues into frenetic action. Mrta Fbin's expert solo work awakened a whole host of disparate sounds, from hissing cymbals and Fafner-style brass to the guttural croak of a contra-bassoon.

But the real reprisal came when the full orchestra thrashed a series of grinding chords; it was like an anguished cry from a lost world, although the closing gesture was relatively modest, even calm. Eotvos weathered his own storm with stoical forbearance and the occasional leap towards a climax. It was a titillating experience, although I have to admit more than a smidgen of cynicism at hearing yet another modern work that ruffles the senses without haunting the memory.

Still, Bartok's untamable Second Piano Concerto was close to hand. Here, Eotvos retained the "back-to-front" orchestral layout favoured for his own work - and what a joy to see a pianist exhibit such obvious relish in the orchestral score. There were times when Peter Frankl's enthusiastic prompting (leaning this way or that at the keyboard) quite upstaged the conductor's; at the fanfare-style tuttis in the first movement, for example, where Frankl virtually leapt from his seat. The performance itself was more big-hearted than steel-fingered, a sonorous, relatively free-wheeling account, with much adroit solo work (save for a messy start to the first movement cadenza). Frankl's survey of the magnificent "interrupted" Adagio recalled something of Bartok's own improvisatory piano style, while the playfully sparring finale had them stamping in the aisles.

Beyond the second interval, Eotvos tended Debussy's Prelude a l'apres- midi d'un faune with much affection and just a hint of self-consciousness, before presiding over Jonathan Harvey's strangely compelling Madonna of Winter and Spring, with the composer himself leading a team of sound projectionists from the centre of the arena. Harvey's haunting journey encompasses a quadrophonic dialogue between acoustic instruments and synthesisers, starting with "Conflict", progressing through the more mysterious "Descent" and "Depths" until Mary herself prompts active regeneration - a sort of celestial "before and after".

For me, the middle sections worked best, mostly on account of their deeply atmospheric employment of texture and harmony, although gathering trumpets raised a regal storm later on. However, the actual performance (a good one, I'm sure) was all but ruined by what sounded like an electronic "earth hum", the sort that would have rendered a recording absolutely useless.

Still, what we did hear "unhindered" (most of it loud) worked well and the promenaders, or at least some of them, took to their listening task by lying on the arena floor like indoor bathers. Others, however, crept discreetly towards the exits, confused - maybe even a mite intimidated - by Harvey's eerie evocation of Matters on High.