It’s so quiet a pin could drop and your eardrums would pop.

Four individuals walk slowly onto the stage; as they settle into their positions a hush descends and all and sundry point their faces forward, towards an equally muted quartet now bathed in a flood of red. A few whispers tickle the ear canals of those towards the back, but that murmuring aside we could conceivably be in the catacombs of a church: it’s dark and silent, bodies packed tight and ready to receive tonight’s sermon. It’s one that needs no words for its effect to be at times overwhelming, at times so heart-piercingly affecting that all a man can do is shut their eyes and let the moment whisk them away, like Dorothy and her little dog in a whirlwind. This isn’t London anymore, not on Mono’s watch.

Dirty streets and dirtier people dissolve from the individual’s thoughts as the Japanese instrumental act – to categorise them as simply post-rock carries certain implications that shouldn’t be permitted the chance to lay roots within your perception; their emotional hold on an audience is quite unlike any of their peers – raise the volume slowly and gracefully, certain songs only truly filling the packed room at the six-minute mark. Four minutes and a barrage of drums and riffs later all eyes are staring upwards, everyone in The Underworld holding their breath as they pray the roof doesn’t fall in.

Though the walls are shaken in earnest this evening, it’s not Mono’s bombast that sets them apart from the crowd: each and every instrumental rock act in lands far and wide can master the quiet-LOUD-quiet thing given a couple of Mogwai albums and the right set of pedals. Where Mono excel is in the execution of these admittedly often formulaic arrangements: there are undulating waves of crisp guitar tones and shimmering cymbal rushes, each fresh impact triggering the tiniest of lumps to begin forming in the throat. When they strip away the senses-shredding noise, Mono reveal a tenderness that few acts renowned for thunderous performances can muster: it’s during these essential lulls, the breaks in the assault, that said physical by-products of such a stirring set are permitted the space to grow. Tears fall, of that you can be sure; whether you see them or not through barely-open eyes is another matter. Visually, Mono aren’t anything special; aurally, they’re at times absolutely otherworldly and consistently able to point their audience down a yellow-brick road to spiritual fulfilment.

They leave to a choir of encore-requesters, each and every mind and soul literally crying out for more. Not a word is returned the front row’s way. And not one needs to be. Two minutes later, outside, it’s not so quiet: the ups and ups of the last hour-twenty reverberate around the brain, the ears’ ringing just a temporary reminder of another Mono show that’ll live long in the memory.

Photographs by Lucy Johnston