The Klangforum Wien is such a disciplined ensemble that for them ever to be remotely fazed or challenged by a piece, even those works with Ferneyhough-like unfulfillable demands, is scarcely imaginable. That the non-physical playing and preternatural calm works alongside their commitment to absolute precision and never sounds passive, or worse, antiseptically scrubbed into oblivion, is what makes them one of the world’s finest contemporary music ensembles.

Pierre Boulez’s habitual reworking of earlier scores has often proved revelatory, but, despite some finely-wrought filigree, Mémoriale struck me as unusually placid for a piece that emerged from ...explosante-fixe.... There wasn’t anything wrong with the playing or indeed Eva Furrer’s flute solo, but there could have been slightly more colour and character. The monotony of Morton Feldman’s Instruments II, by contrast, had little to do with the ensemble: in the manner of Cage – manner being the operative word – this piece gives the impression of leaving things to chance in a paradoxically stylized way. My problem wasn’t so much that Feldman was having his abstract expressionist cake and eating it; what others may have perceived as slow-moving, serendipitous beauty I found rather dull and inconsequential, with chance events oddly wedded to an anaesthetizing periodicity.

Time Out is one of those Beat Furrer pieces that starts off promisingly and soon drifts; what has been termed in musicological German the Einfall (creative impulse, or musical idea) is Furrer’s strong suit, not development. The idea in this case was to pair off the strings and explore some interesting spatial effects, which the Klangforum did musically and visually, with all non-essential movement minimized and the pairs operating as indistinguishable units. Playing was clean, efficient, and yet poetic. The drift set in when these dialogues broke down to make way for some inscrutable contributions from the flute and harp soloists. In his programme note Furrer claims that the piece manoeuvres itself into a Kafkaesque cul-de-sac. I was not convinced.

Olga Neuwirth’s ...miramondo multiplo... was one of the two highlights of the evening. Neuwirth at her best – the collaborations with Elfriede Jelinek and chamber work gems such as Quasare/Pulsare come to mind – is the most significant Austrian composer of her generation, but even a less seriously intended piece like ...miramondo multiplo... puts a depth of intellect and meaning between itself and the irreverent ‘Third Viennese School’ of HK Gruber and Kurt Schwertsik, from which a part of its inspiration is derived. That this piece was originally programmed at the end of the concert and then moved to before the interval made for interesting proximity with the Boulez; echoes abounded, not only of ...explosante-fixe..., but also of Répons and of Pli selon pli. But if Neuwirth’s piece can be said to be modelled after anything, it is Berio’s Sinfonia: there is a referential collage, which like Berio’s includes Mahler (the opening of the Fifth Symphony subsides into ‘Send in the Clowns’ and it’s disconcertingly unfunny).

Such is the strength of Neuwirth’s writing, though, that the allusion and stylistic borrowing are never without their place in the integrity of the whole. There’s no trace of ironic postmodernist posturing, even when Neuwirth gives Handel’s ‘Lascia ch’io pianga’ the Harlem Gospel treatment; in refracting the borrowed vernacular through her own kaleidoscope, she makes it fully her own. The Klangforum understood this entirely: Handel didn’t sound like Handel, and while Neuwirth is rather besotted with Miles Davis, solo trumpeter Anders Nyqvist played it straight. Conductor Jean Deroyer gave a lively reading of the score which deftly steered clear of the party-piece treatment the work invites.

Friedrich Cerha, whose lifetime’s work was recently recognized with the Ernst von Siemens Foundation’s 2012 music prize, has entered a meditative phase as of late. Bruchstück, geträumt is similar to some of the new solo piano pieces he has written, with contemplative statements based around, again, the ‘idea’ as in German. The way Cerha phrases this in his programme note exploits an ambiguous double meaning: the idea could be something that emerges from within, or an autonomous stimulus which occurs fully formed to the conscious mind. Applying this ambiguity to the themes of individual style and sedimented conventions, Cerha shows (to paraphrase Morton Feldman) how what we may assume to be one of these could be perceived as the other. Expressed musically in Bruchstück, geträumt, with the typical lucidity of Cerha’s writing and his skill for orchestration, all of this is much clearer than I have worded it. The Klangforum gave this an intimate performance, giving voice to Cerha’s discourse in subtle and thoughtful ways.