Polystylism was until quite recently a backhanded compliment thrown at Schnittke, and yet the presence of the Third Quartet is hardly required to issue a reminder that Beethoven – like Stravinsky, for that matter like Bach – listened deeply through what counted for music history in his own era, took what spoke to him and made it his own. Nevertheless, the coupling works, as the Britten Quartet established when they made their debut album (Collins Classics, 4/90); and following on from the Danish String Quartet’s well-received first ‘Prism’ volume (12/18) of Op 127 with Shostakovich’s last quartet, Schnittke’s annexation of DSCH to the opening notes of the Grosse Fuge to form a hybrid leitmotif acquires an even more compelling logic in this new, immaculately engineered album.

Versatility is a signal virtue of the ensemble: their smoothly planed, viol-like pure tone in the opening Bach fugue (to close Book 1 of The Well-Tempered Clavier, the one with all 12 notes) as well as the Lassus cadence which opens the Schnittke (this album is full of doors closing on to new and initially disorienting rooms) carries no trace of irony or displacement. It’s natural music-making, and no less winning in their ways are the quartet’s blithe assimilation of 18th-century minuet style in the Poco scherzando of the Beethoven, or the bleak electrical buzzing in the finale of the Schnittke.

Without underplaying the changes of tack which make the opening movement of Op 130 Beethoven’s most puzzling quartet movement, the DSQ find elegance and continuity here, too: the omission of the repeat paradoxically carries the listener through its eddies of thought as if on a canoe journey so eventful that there’s no time to consider imminent peril. Even a deeply considered account of the Cavatina – more soulful pure tone here – does not interrupt the momentum towards an account of the Grosse Fuge that’s as beautiful as it has any right to be, no less unsettling in that regard than much tougher and self-consciously ‘modern’ accounts.