LSO/Gergiev, Barbican Hall, London <!-- none onestar twostar threestar fourstar fivestar -->

A fiery start to the honeymoon

Giant screens flanked the Barbican platform, proudly displaying photographs of the London Symphony Orchestra's newest acquisition. Should anyone have needed reminding that Valery Gergiev had finally arrived, then here was the evidence - the world's most sought-after maestro in rehearsal for his debut concert as principal conductor. If you've got him, flaunt him.

Of course, the title "principal conductor" can, in practice, mean little more than a commitment to a dozen or so concerts a year, and who's to say yet whether Gergiev's insane international schedule will allow for the kind of deepening relationship that the orchestra and its audiences currently envisage? We shall see. For the time being it's very much a case of enjoy the honeymoon.

Broadly speaking, there are two kinds of conductor - the intellectual and the inspirational. Gergiev sits squarely in the latter category, meaning that when and if he's thoroughly prepared (and it's a big "if"), when and if the fires ignite, then there's no touching him. His debut series - Stravinsky, Debussy, Prokofiev - finds him in a familiar place, though I imagine you could count on one hand, if at all, the number of times he will have opened a concert with Stravinsky's weirdly extravagant mini-cantata The King of the Stars.

If ever a work was conceived with complete disregard for practicality, then here it is. Lasting little more than five minutes, this strangely diffuse confection fields a huge orchestra and horribly exposed male voice choir in a kind of mystic peasouper. Stravinsky dedicated it to Debussy (absent from this programme), who will surely have been appalled by its vagueness.

Gergiev himself seemed puzzled, his head in the score. Still, the LSO Chorus's intrepid tenors nailed the opening cry of "Zvezdoliki" ("The star-faced one") and a shimmer of violins gave notice of mesmerising pianissimi to come.

If The King of the Stars represents a kind of planetary meditation, then Prokofiev's Scythian Suite is the universe exploding. Its paganistic fire and ice brought terrific virtuosity and untold decibel levels from the LSO. The trenchancy of the strings in the second movement's "Dance of the Black Spirits" will have been felt as well as heard from the very back rows. The final sunrise was the aural equivalent of looking straight into the sun.

Creating atmosphere is one of Gergiev's great gifts as a conductor. Note how he avoids making pauses between movements, remaining poised and primed for the next sounds we hear. The Scythian Suite, though, is primarily about revelling in the sheer noise it makes. And, my goodness, it did.

Ditto Alexander Toradze, the unrelenting pianist in Stravinsky's Concerto for Piano and Wind. Toradze is a great favourite of Gergiev's, so expect him to be wheeled out at every possible opportunity. And expect the piano to be wheeled off and probably written off, too. Let's just say that Toradze is a zealous player who, in this somewhat demented parody of baroque point and counterpoint, was hell-bent on hammering the wilful syncopations as vindictively as he could. He can play quietly, as the remote cadenzas of the slow movement demonstrated. For the most part, he chose not to. The concerto's acerbic brand of ragtime is wittier than that.

So, a splashy first half. But no sooner had Gergiev prepared the way for our first steps into the enchanted garden of the ogre Kashchei at the start of Stravinsky's The Firebird than the magic descended. His voluptuous reading of the complete ballet excited every fluttering nuance of this quixotic and beautiful score. Its folkloric earthiness was uncommonly vivid, with sensational work from the LSO wind choir and a depth of string tone that opened up at least one unimaginable soundscape in the "total eclipse" of the final scene. Here's hoping that more where this came from will mark out Gergiev's LSO adventures.