Black-haired, big-eyed blokes in black coats and boots, with rows of cartridges on their chests, long knives on their belts. Not the advance guard of an invasion, but singers.

As Georgian culture has become more city-centred and pop-influenced its unique polyphonic singing has been seen as threatened, and it’s on UNESCO’s list of Oral and Intangible Masterpieces of Humanity, but a new wave of singers are embracing it.

Outstanding amongst them is Alaverdi. The quartet performs songs, from across Georgia’s ten regions, church chants and old songs from pagan era in rich, shifting harmony of deep bass, strong baritone and soaring tenor rising on occasion to a mad, wild, crowing falsetto, with added variety from Georgian traditional stringed and wind instruments.

Singing for these guys, and in Georgia in general, isn’t just an intense stage performance, it’s a social thing; at the long table of a supra, a feast that’s at the centre of Georgian life, the many courses and Georgian wine just keep on coming and so do the toasts and songs.