It is good to catch up at last with Olga Neuwirth’s chamber output. This new Kairos disc features works from the later 1990s – a period culminating in the opera Bählamms Fest (6/04) – which are as immediate in their impact as one would expect.

Framing the collection are two pieces for string quartet. Akroate Hadal is typically uncompromising in its collision of expressive types and playing techniques, in music whose antagonisms finally merge into a ‘vanishing point’ of ethereal harmonics. Its compendious nature is explored further in settori – less a successor than a distanced commentary which is briefer in duration though no less visceral.

Whereas both pieces cohere in spite of their apparent disunity, …ad auras…in memoriam H revels in the harmonic and rhythmic de-synchronisation between two violins; it’s less engrossing than it might be, however, with passages of ‘coming together’ against a unifying drum beat impeding rather than intensifying the flow.

Most impressive, in its revitalising of a difficult medium, is Quasare/Pulsare in which the extensive but subtle ‘preparing’ of violin and piano gives rise to a new textural range that the instruments exploit to an extreme but intelligible degree. Likewise incidendo/fluido, where the narrowed compass of the keyboard is extended ‘from within’ through the sound of an ondes martenot activated via a CD player. Equally radical is the transformation of viola d’amore in …?risonanze!…, the instrument becoming a hybrid of string and keyboard in a terse, agitated monologue.

Performances are as dedicated as one would expect from the musicians involved, with vivid yet focused sound. Stefan Drees contributes a not-too-abstruse booklet note, and the disc reveals another side of this most combative of composers.