BBC Proms: BBC Singers, Sinfonye, Hollingworth, Wishart, Cadogan Hall

Twelfth-century abbess, healer and mystic Hildegard of Bingen had no formal musical training. Perhaps because of this her music – exquisite arabesques of chant melody, animated by the conviction of her religious beliefs – creates a language all its own, a “swaying bridge between heaven and earth”, as she characterised it.

Contemporary composer Stevie Wishart herself provided a bridge between the medieval mysticism of Hildegard and the more earthly concerns of Harrison Birtwistle and Benjamin Britten, in a Proms Saturday Matinee at Cadogan Hall that invited its audience to meditate upon the sacred and the profane.

Together with her ensemble Sinfonye, Wishart is currently engaged in a project to record the complete works of Hildegard. Her immersion in this repertoire has left its traces on her own composition, a process vividly dramatised in the concert’s centrepiece – the world premiere of Wishart’s Out of This World, commissioned by the BBC for this year’s Proms. Taking four of Hildegard’s own religious hymns whose music is now lost to us, Wishart sets them in a style that remains faithful to her own textural, loose-limbed experimentation while also paying homage to the original composer.

We open in the chilly “light of the first dawn”, an episode for men’s voices that seems to grow out of primordial confusion to take melodic shape and form. Emerging from a low drone, fragmented text and melody is divided hocket-like among the voices, its meaning reduced to syllabic noise and effect. Wishart’s textures are minutely layered, twitching motor rhythms in the inner parts supporting the melodic flurries of almost Monteverdian virtuosity. High tenor writing brings emotions to a head, their athletic embellishments recalling the expansive writing of the Eton Choir Book composers Fayrfax and Cornysh.

The central movements experiment further with textural effect (including some particularly striking cluster-chord wails in the sopranos in "O facture dei"), but it is in the final "O eterne Deus" that Wishart finally releases her full forces, adding the female voices of Sinfonye to the BBC Singers to conjure a dense and shimmering cloud of sound that echoed from Cadogan Hall’s galleries, catching different harmonic lights and exposing hidden seams of metallic brilliance. On the strength of this movement alone I’d make the journey to hear this slow-release work for a second performance.

Sinfonye opened the concert alone, the grumble of Wishart’s hurdy-gurdy growing through the hall – a rough herald to the highly characterised purity of her singers. Performing a sequence of extracts from Hildegard’s Symphonia armonie celestium revelationum they coiled and weaved as one, the single line occasionally splitting into angular organum or occasional moments of harmonic resolution. Lovely though it was in a secular setting, I longed for the context and acoustic of a church to offer Hildegard’s writing the resonance the composer so clearly intended.

Along with certain other BBC ensembles, it’s hard not to think that the BBC Singers might be tiring a little at this stage of the Proms season. Neither Birtwistle’s Narration: A Description of the Passing of a Year nor Britten’s Sacred and Profane are works to be underestimated technically, and while under Robert Hollingworth’s efficient direction the group were never less than solid, there was something lost in the copy-bound faces and lacking in the delivery that spoke of weariness.

The operatic fullness of the BBC Singers was never going to be an ideal fit for the lithe contortions demanded by the Britten, and at times seemed actively at odds with the music. The medieval texts were often lost in the vocal texture, and the playfulness of "Lenten is come" in particular (spring “bustin’ out all over" as Christopher Cook had it) lacked spontaneity. The Birtwistle fared better, offering more scope for the choir’s strengths of vocal power and collective characterisation.

This year’s Saturday Matinees have offered some of the most exploratory programming of the Proms season and this was no exception. A well-conceived programme may have yielded mixed results, but must surely ensure the return of Wishart’s music – surely among the finest of this year’s new commissions – to the festival.

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