As far back as 1906 Ravel imagined a piece that would be 'the apotheosis of the waltz' in tribute to Johann Strauss II.
It was the impresario Diaghilev who made Ravel focus on it at last, by asking for a piece for his Ballets Russes.
Ravel had suffered during the war years. His dangerous service as an ambulance driver on the Verdun front left his health in a precarious state, and he lost his mother in 1917.
'La Valse', when he finally came to compose it, is written for a ballroom balanced on the edge of an abyss.
The rhythmic pulse for the waltz rises out of the depths like a disturbed heartbeat. The sense of unease grows, with stabbing notes on the horns and uncomfortable shivers in the low strings. When the melody fully emerges it is a ghostly, fairy-tale waltz.
With careful listening, a recurring intrusion of the orchestra's deepest instruments can be heard, rumbling like distant artillery.
Recorded 9 September 2017, Michael Fowler Centre, Wellington by RNZ Concert
Producer: David McCaw
Engineer: Graham Kennedy