If I’ve unpacked it right, there are two converging strands to this project: the atmosphere of ‘that fleeting moment between the end of the night and the beginning of the day’ (the blue hour) and, not unrelated, the parallel sound worlds of Hildegard and Hartmann – composers whose very individual takes on spirituality, sacred and secular, led them to insubordination.

The album has an affecting ‘sound’ that is perhaps its biggest success. Listen no further for what Le Concert Idéal actually mean by the ‘blue hour’; something tense, hesitant and misty but neither overbearing nor new-agey, and that forms a firm interpretative starting point for all the music, bringing us an ‘album’ in the traditional sense. Sometimes we have the impression of music played with closed eyes, as in Hildegard’s three Visions, placed as three pillars in the programme that create a modal foundation for everything else. But the abbey acoustic is harboured just as effectively in the chase-downs of the Shostakovich and Hartmann scores. The ensemble have a sense of themselves and their place in that acoustic even when they are sounding more disparate and intricate – the high strings with harmonics at the end of Shostakovich’s Prelude; the thick tone as Hartmann reprises his chorale tune (though the boundaries are pushed in the multi-layered Allegro).

The music is arranged architecturally in the manner of a single, fervent prayer that takes a long time to wind up and quite a while to wind down again. Marianne Piketty is an integrated ensemble leader but a shamanistic soloist, notably in Hartmann’s cadenzas and Hildegard’s calls for a cantor, and excellently manages dynamics and direction from within. She is both prayerful and impassioned in Philippe Hersant’s Une vision d’Hildegarde that, like good architecture, considers its context and surroundings while trying to advance the conversation. An absorbing album with a sure idea of itself – and of the art of recording.