There’s a strange blend, sometimes remarkably so, to this performance by Les inAttendus. Will it replace the string quartet? No, but the trio of accordion, bass viol and Baroque violin offers something uniquely rich. It’s tantalising alchemy when Vincent Lhermet’s accordion makes the string instruments sound as if they work by breath too, with bellows instead of bows. The thrilling complexity of this sound world first emerges in Contrapunctus IV: the instrumental lines crawl on top of each other like centipedes over the skin, yet there remains the subtly shaded luminosity of timbral difference. There’s a tactility to the counterpoint that I haven’t encountered in The Art of Fugue since Fretwork’s recording (Harmonia Mundi, 12/02). It’s fabulous.

I’m most appreciative of how Les inAttendus end movements – odd praise, perhaps, but there is such stylishness to how the ensemble approach a double bar line that warrants exploration. Take the end of Contrapunctus III: growling as if from the belly of a whale. Or Contrapunctus IX, a 4 alla duodecima, in which the energy and agility of Bach’s fugue are worked into how it plays out: there is no slowing down with pompous grandeur here, but instead the coolness of indifference. And then Contrapunctus XII, a close tailored with chic mystery. The music just slips away into the black of night. Details such as these are enthralling against the plague of gargantuan ritardandos that mar many Bach performances elsewhere.

While this is all undeniably lovely, it is not quite enough to sustain my attention. The particular instrumental set-up of Les inAttendus is successful for how it resonates with other idioms of playing, in particular folk music. To awaken a cliché, then: why not provide some dancing muscle among all the brain? Some dances by Telemann or Fux here would change the stakes greatly; the Bach would sound ‘more Bach’, and a listener would be provided with the much-needed texture to all this density. Blasphemy, I hear you cry. But with more than enough Arts of Fugue to last a lifetime, perhaps it’s time to try something new.