Spectral Music is the term coined for the kind of work created by Tristan Murail, the latest composer to be featured in the Philharmonia's free-entry and highly recommended Music of Today series. His methods of exploring and exploiting the acoustic properties of notes may seem overly intellectual on paper, but they make for some evocative music.

Two of his scores, written 22 years apart, were given persuasive performances here by the Philharmonia's team of soloists under the assured direction of Pascal Rophé. The first, Treize Couleurs du Soleil Couchant, started spectrally indeed, with the violin playing barely louder than the air conditioner. Notes on violin and cello were pushed until they became scraping sounds; later, leaps in clarinet and flute gave a subtle suggestion of birdsong (Murail studied with Messaien). Murail's obsession with putting sounds together to create others really worked in this performance, in which every so often a new, unseen, more powerful instrument seemed to enter the room.

Even more vivid was the 2000 piece Winter Fragments. Here a Midi keyboard was added to the five initial instruments, sampling their playing, and providing a noise of bells that sounded like icicles on a string.

They preceded an evening programme by the Philharmonia en masse, liberally laced with sex, death, beauty - and mobile phone ringtones. One of these led the conductor Hugh Wolff to leave a longer than normal gap between the first and second phrases of a heady but almost laboriously slow Prelude from Wagner's Tristan und Isolde. But nothing disrupted Mark Padmore's direct, airy communication of Britten's Serenade for Tenor, Horn and Strings, in partnership with Laurence Davies, nor the excerpts from Prokofiev's Romeo and Juliet. The latter didn't quite convey the uneasiness that lies behind the love music, but was as loudly, richly red-blooded as one could wish.