In 2006 Elliott Carter’s longevity and Pierre Boulez’s slow-coach approach to composition met in the middle, when Carter, then 98, was finally able to hear a finished version of the work Boulez had originally dedicated to him for his 80th birthday. With its creamy centres encased within slabs of fruity roughage, then sprinkled with hundreds-and-thousands of vibraphone and marimba notes, Dérive 2 sounds like birthday cakes ought to. The basic recipe Boulez followed was that of the medieval hocket – an antiphony of sound generated by splitting a single line between sparring instrumental voices. Birtwistle and Andriessen construct grand structures that rebound out of hockets too, but Boulez turns the function of hocketing against itself.

Intriguingly, Robert Piencikowski’s technical explanation of Dérive 2 in Naïve’s booklet-note directly contradicts Wolfgang Fink’s note for Boulez’s own 2002 DG recording (admittedly of an earlier, shorter version – 5/05). But the basic point still stands: Boulez overlaid rhythmic cycles borrowed from Carter, Ligeti and Nancarrow, then de-familiarised these objets trouvés using hocketing techniques.

On DG Boulez presented a 24-minute version. The dawning realisation midway through this 50-minute redux of 20-plus minutes still to go could be alarming but Daniel Kawka’s intelligent, plugged-in direction locates meaning within the labyrinth. Musical structures tend to spill outwards but this structure obsessively folds back into itself, and Kawka bigs up Boulez’s wedges of disruptive near-stasis. As these interruptions migrate from background to foreground and become the piece, the structure rotates 360 degrees on its axis – cannily aided by Kawka’s protractor-like interpretative angle.

No such mysteries surround the easily digestible Dérive 1, and it’s a shock how coquettish, fluffy and downright decorative Mémoriale sounds these days. After Dérive 2’s well-cooked stodge, meet Pierre Boulez, purveyor of fine sonic cup cakes.