'Architect in Sound' was the subtitle for this weekend, a celebration of the music of Iannis Xenakis and a rare opportunity to experience the body of work of this extraordinary composer.
Born in Romania of Greek parents in 1921, Xenakis demonstrated among other things the ability to wring unexpectedly vivid sound effects from instruments whose capabilities had apparently been exhausted in the past.
This first concert of five was an ideal exposition of his work, two shorter vocal pieces balanced by two more substantial works for instrumental forces. Of these, Shaar stood out as the most accessible and tuneful, its swooping opening melody executed in unison by sixty strings of the BBC Symphony Orchestra - as exciting visually as it was aurally. The sound was warm and rich, perhaps too rounded at the edges, but the players crammed onto the QEH stage made much of this remarkably graphic score, portraying as it does the immense gate of a city.
Perhaps the music also seemed more sonorous after hearing Nuits, a choral 'protest' work devoid of real words but making remarkable use of the BBC Singers' guttural sounds. Using tuning forks to hone their accuracy of pitch, the singers demonstrated agility and expression beyond the call of duty, ranging from extended, angry stammering to snatched cries from the male voices. Whistling, frequent outbursts of rage, subterranean bass notes and half-words mingled together until a powerfully hushed unison at the end, finishing with a kind of coughing sound, the last of the composer's tortured anger laid bare.
Compared to this, the opening Sea Nymphs, where the composer breaks up the text of Shakespeare's Full Fathom Five, was hugely impressive but less effective, though there was still plenty to admire in Xenakis' word painting.
After the interval came Alax, its intriguing layout consisting of three groups of ten musicians, at least in theory - one of these three groups had somehow gained an extra horn player. Xenakis uses these forces to exchange musical ideas across the stage - again exciting in the visual sense. Breathtaking textures included the combination of searing, high register violin harmonics, short brass phrases and steady bass drum tread. The unexpected sonorities and harmonies became ever more spellbinding until the close, the three percussionists hammering in union. Conductor Jac van Steen, excellent throughout, felt sufficiently moved to rush up to the composer's widow in the audience, as if to congratulate her on her husband's achievement.
A generous if challenging programme included music by Varese and Stravinsky. The former's Integrales, belying its age of eighty years, could have been harsher of tone in these hands, although it was amusing to watch the 'lion roar' effect, secured through a strange looking drum, using what looked like the starter for a lawnmower!
Tailing the programme was a slightly perfunctory performance of Canticum Sacrum, a work demonstrating the economical scoring of late period Stravinsky. This took nothing away from the main act, however - Xenakis had already made his impact, the chosen pieces and performances an ideal start to a gruelling yet surely rewarding weekend.