Edinburgh International Festival Opening Concert, RSNO, Knussen, Usher Hall

On paper this was an interesting programme. The Edinburgh Festival traditionally opens with a major choral work, but while the international audience would probably be happy with endlessly recycled requiems and masses, festival directors have often felt obliged to venture into more challenging territory.

So for last night’s opening concert the chorus had prominent roles in two separate works on either side of the interval: Scriabin’s Prometheus, The Poem of Fire, and Debussy’s Le Martyre de Saint Sébastien. While there is a superficial resemblance between the hazy tonal landscape occupied by these two composers, there is in fact a world of difference between Scriabin’s voluptuous sensuality and the terse, almost ascetic orchestral colouring of Debussy.

On their own these two works would have meant a short programme so length, if not weight, was added by Schoenberg’s Five Orchestral Pieces, early works that peer cautiously at the atonal future from within a post-Mahlerian chromaticism (they were actually composed a year before Mahler died, and first performed by Sir Henry Wood at the 1912 Proms, believe it or not). This performance by the Royal Scottish National Orchestra under Oliver Knussen (pictured below at last year's Proms by Chris Christodoulou) was precise, measured, but ultimately lacking in incisiveness. Granted, music as flighty and insubstantial as this is unlikely to pin you to your seat, but the RSNO players, normally so committed, seemed disengaged.

The same sense of mild ennui enveloped Prometheus. Scriabin was a ludicrously extravagant composer, for not only is this a quasi-concerto for piano, elegantly played by Kirill Gerstein, but the vast orchestra is augmented in the closing moments by wordless chorus and organ, which at one stroke makes the piece complex and expensive to perform. Last year, we heard his astonishing First Symphony, likewise confined to rare outings thanks to a disjointed choral finale with two soloists.

Despite its preoccupation with Scriabin’s “mystical chord” (A, D sharp, G, C sharp, F sharp, B), Prometheus is propelled by a clear thematic device that gradually builds in intensity, but this was a performance where the notes were left to fend for themselves. This could work with master-orchestrators such as Mahler or Strauss but Scriabin fumbles with his lavish orchestral forces, including an impressive array of percussion, and needs more help from conductor and players to add spirit to the opulence.

Debussy’s Le Martyre de Saint Sébastien is billed as an oratorio but is in fact a bit of a contrivance, being the incidental music plucked from a five act mystery play by Gabriele d’Annunzio (more often performed are the Fragments Symphoniques made up of music taken from the full score.) Without the play, or even the narration that precedes each of the five acts or “maisons”, the resulting collage of solos and choruses is distinctly on the dotty side of mystical, with words such as “women unfasten your girdles! From dark Hades, the abode of souls, He has come back to us, the blessed one” more likely to produce a snort of derision than fellow feeling.

An orchestra stripped of Scriabin’s excesses produced a sound of greater clarity and finesse than before the interval. As the principal soloist Claire Booth (pictured outside the Usher Hall by Clark James) floated a sinuous vocal line with an authentically piquant French timbre. With more to get their teeth into, different bits of the chorus were up and down like ninepins and coped well with Debussy’s diaphanous harmonies. But ultimately this is a somewhat unapproachable work so if you were seeking the “wow” factor on the first night of one of the greatest festivals in Europe then such a strange programme could only be rather a disappointment.

• Full details of EIF concerts on the website