A major-label debut for a composer in his fifties – the Latvian Radio Choir’s latest release is an intriguing prospect. These superhuman singers and their artistic director Sigvards Kļava introduce their audience to the choral music of Alfred Momotenko-Levitsky, a Ukrainian-born Dutch composer. There’s a generous sampler here – everything from three-minute motets to the substantial, multi-movement On the Passion – and it’s more than enough to get a sense of the breadth of a voice that draws on Orthodox Church chant as well as contemporary Western choral writing.

In a booklet essay, Momotenko speaks of the ‘intensive choir tradition’ of a childhood spent, nomadically, in Ukraine, Moldova, Georgia and Russia. But a career that drifted into sonology and sound installation took him away from acoustic composition until recently. Some five years of collaboration with Kl,ava and the LRC now results in this collection of spiritual (rather than strictly liturgical) works.

The recital is cleverly structured. We start on familiar ground with Creator of Angels – a setting of lines from Bella Akhmadulina (distilled here into a shorter whole) that supplicate for mercy. Threads of Znamenny chant run through thick vertical textures, always rooted in wide-spaced bass parts. The effect is ancient, but softening into 21st-century lyricism. We hear flickers of Silvestrov, Tavener and Ešenvalds, but also of Chesnokov, Grechaninov and their ilk.

Then we start to push off from land – gently at first in the short Three Sacred Hymns, with their modal harmonies and sinuous lines that always seem to tug back to the fixed point of unison, and then more rhapsodically in Lullaby: upper voices an endless flat horizon, harp ripples and sound-bursts silhouetted against them.

We’re in another world by the time we reach On the Passion. This setting of Pasternak’s poetry from Dr Zhivago (this time intended as a companion for Rachmaninov’s Vespers) is a trove of imagery. Birdsong, bells, Holy Week processions and folk dances draw a musical ‘essay’ from Momotenko that extends the composer’s harmonic and textural vocabulary with nonsense syllables and stamping – effects as well as melodies. Voices are fragmented down to endless solo strands (the technical challenge is immense), intersecting and coming together with Ives-like sonic cinema.

Kļava marshals his singers with unobtrusive precision. The 24-strong group are shape-shifters, slipping imperceptibly from chorus to soloists, from knitted web to filigree strands. Balance, not dynamics, is the principal expressive force here. Kļava pulls details and lines forwards or pushes them back flush, creating the depth and play of light that really makes this debut sing.