The Sixth Quartet features orchestra in what is less a concerto concept than an extension of the quartet’s sound world on to a larger expressive canvas, the first movement setting up harmonic and rhythmic premises which its four successors build on in a visceral yet ultimately inconclusive manner, the discourse running down to an uneasy stasis. By contrast, the Seventh Quartet consists of 21 brief movements – each a variation on the motivic fragment heard at the outset – that can be heard as falling into three larger groups whose impetus is channelled towards increasingly stable and cohesive effect, the music reaching a calm which is audibly devoid of exhaustion. Both pieces reaffirm Dusapin’s quartet cycle as among the most significant now emerging.  Richard Whitehouse