Eska/Spiro, The Foundling Museum

There have been memorable nights at the Foundling Museum recently, with Alasdair Roberts delivering a superb solo show in April, while on Friday the Nest Collective hosted a double bill of Zimbabwean-born singer Eska and Bristol’s masters of English folk minimalism, Spiro.

I’d seen Eska at Essaouira’s Gnawa Festival last year, performing with Soweto Kinch and Hamid El Kasri – she was so good they invited her back with her own band this year – and on the strength of her opening set in the Picture Gallery, the folks in Essaouira have chosen well. She has a powerful, emotive, and mellifluous voice and delivery.

'Yellow Noise' – inspired by Emily Dickinson’s term for sunlight – feels intensely transportative

Spiro’s instruments – accordion, fiddle, guitar, mandolin – are those of the period in which the great and good, whose portraits hang on the walls around us, gathered to establish the Foundling Museum in the 1740s. Spiro’s music is not of that world, though, it’s of ours, drawing on minimalism and systems music as much as from the dances and folk tunes that may well have rung out in the 18th-century streets around Coram’s Field.

The room’s rich, reverberating acoustic suits them well. The geometric crescendos of “Cathedral” and “The City and the Stars” (see video below) are rousing and hypnotic, with the latter’s beautiful tune (“Too Long You’ve Been Away”, from the north east) flowing and undulating against a subtle organising structure that’s more rippled than fixed. ”Yellow Noise” – inspired by Emily Dickinson’s term for sunlight – feels intensely visual and transportative, as if you’re being propelled at speed over a rolling land- and sky-scape on a music that opens its own vistas, unfolding in structure like an Escher infinity drawing in sound.

At times, guitarist Jon Hunt, mandolin player Alex Vann and fiddler Jane Harbour cluster together under the portrait of George II, stoking their parts while accordionist Jason Sparkes stands to one side, controlling the bass and drones, embodying the physical pull of the music. It’s hypnotic and fluid enough to have a distinctly physical effect. On the likes of “Shaft”, you feel the old tune of “Bobby Shafto” seeping through its modernist new setting, like damp through a wall. The suspended violin pulse of Arches eases into the swift-running, full-tilt tune of “The White Hart” before an encore of “We Will Be Absorbed”, a meditation on death and re-absorption into cosmicness, and it seems Spiro are intent on hypnotising us there.

• Spiro’s Nest Collective residency continues on 15 June