An air of mild confusion hangs over tonight’s show, which was downgraded from Cottiers theatre to the emphatically less glamorous environs of Audio at short notice. Sadly, spectators are thin on the ground, suggesting that low ticket sales may lie behind the last-minute relocation.

Best known for her work with Swans in the 80s and 90s, Jarboe’s subsequent solo discography has run the gamut from minimalist folk to sludge-blues dirges to industrial metal. To each instalment she lends her incantatory vocals, among the most striking in the history of heavy music.

Tonight, she enlists the talents of Italian duo Father Murphy (Freddie Murphy on guitar and Chiara Lee on drums/synthesisers), who essentially perform two sets: the first as support act and the second as Jarboe’s backing band.

Their support set is an immersive experience, with more than a few moments of terrifying beauty interspersed throughout. Opener Cavalry conjures post-apocalyptic imagery of blasted wastelands; Murphy and Lee’s dual chanted vocals are the howls of deranged zealots roaming the barren landscape. Musically, there’s little more to the track than their feverish exhortations and the scraping of sticks on a drum: the ritualistic qualities with which Lee imbues this repetitive task are as much a part of Father Murphy’s performance as the music itself.

This is head music with lofty ambitions, elevating their priestly gimmick into something very affecting. The only downside – a major one – is the lost opportunity of seeing them in the altogether more fitting surroundings of Cottiers (a converted church for those unfamiliar).

After an interval, Jarboe takes to the microphone, with Father Murphy once more providing the musical accompaniment; which this time is more restrained, as Lee’s keys approximate the more organic tones of organs and harmoniums.

Hearing Jarboe’s voice is, as expected, thrilling. On Blood On Your Hands, from Swans’ Anonymous Bodies in an Empty Room (1990), she narrates from the perspective of an possessive yet infanticidal mother, chastising her wayward child in what could scan as an analogy for humanity’s avaricious ways with Mother Earth: ‘Baby, there’s blood on your hands/Mama’s gonna get even with you/When the blood’s washed over you, mama will never forget’.

Jarboe’s voice rises and falls, rises and falls; hinting at a full showcase of her mercurial abilities but never quite unleashing it – and before I know it, the show is over, with the headline act having performed for barely half an hour before unceremoniously leaving the stage. Murmurs of bewilderment echo through the crowd, most of whom I suspect expected more than was delivered – a sad thing indeed, given what we all know Jarboe is capable of.

For more on Jarboe and her tour click here.