The Ensemble Contretemps APA Concert Hall, June 7 As one would expect from a Swiss chamber group, The Ensemble Contretemps is clean, crisp and transparent, with six artists of incredible virtuosity. For the contemporary music which they played with such control was imperative. Typical was flautist Felix Renggli, playing the solo (t) air (e) by Swiss oboist Heinz Holliger. The punnish title means basically 'to shut up', but Renggli did nothing of the kind. With a thematic motif basically a percussive tapping on the flute key, he uttered notes which would seem impossible. I couldn't catch the construction (if there was any), but the whistles, low down gurgling, almost sensuous heavy breathing and virtual double-note playing received applause rarely offered to more established works. But the concert had far more, beginning with Wen Deqing's Le Souffle for the entire quintet. Dequin is obviously a student of the most abstruse Viennese music, for his piece began with what one might call today 'virtual' music. That is, one note at a time, maybe two or three, pointed by each instrument, a technique developed in the 1920s by Webern, but today almost forgotten in favour of easier if more bloated music. Like Webern, though, Dequin has an expression of colour. Unlike Webern, he did come to a mighty aural climax, but it hardly detracted from the delicacy of the piece. One wished for programme notes of some kind though. And those who didn't know that George Crumb's Vox Balaenae meant 'The Voice of Whales' and that the amplified instruments were imitative of whale sounds probably didn't get it. What they should have got is that Crumb has the most sensitive ears in the world today, and this 'aural minimalism' had an almost religious intensity. Ferneyhough's solo violin chaconne was enigmatic but obviously well played by Isabelle Magnemat, but the Bartok Contrasts, originally for Benny Goodman had - okay, I confess - the jumping Hungarian moods and sounds which were most rewarding of all.