Jonsi, HMV Forum, London

Sonic seer is a wonder of nature

When tonight's set closes, it's difficult to believe that an hour and a half has passed, such is the spell that the Sigur Rós frontman, Jonsi, casts over his audience.

With his Icelandic band on hiatus, Jonsi is accompanied on his first solo tour by his boyfriend and collaborator on the Riceboy Sleeps album, Alex Somers, on guitar and keyboard, Úlfur Hansson on bass, Thorvaldur Thór Thorvaldsson on percussion and Ólafur Björn Ólafsson on piano. It's the continuity of songs all seamlessly flowing into each other, and the ongoing visuals, that keep a narrative and musical thread from beginning to end, while Jonsi's ethereal falsetto rings out, setting the magical other-worldly tone for the night.

Few acts lend themselves to cinematics as much as Sigur Rós, and Jonsi's debut solo album, Go, though its energy is more focused and tightly-sprung, boasts much the same ambience. But Jonsi and his band's inventive performance is a spectacle in itself. On "Hengilas", for example, they play the vibraphone with the bows of a string instrument, while at other points toy-like instruments create scratchy sounds that add to the sonic mélange.

The over-arching theme of Go, namely embracing the natural cycle of life, is summed up perfectly by the lyrics of "Animal Arithmetic", "Every day, everywhere, people are so alive". It's conjured up here both in the projected nature imagery and the performance; in the ebbing and flowing of dynamics, especially throughout the first half of the set, and the wide-eyed childlike wonder that colours Jonsi's songwriting. In one poignant moment, animated daisies open up and wilt only to be replaced by larger daisies and colourful, playful hummingbirds.

With a first half dedicated to sparser, instrumental-leaning tracks, such as the melancholic, plaintive, strings-fuelled "Kolnidur", captivating visuals help to keep the listener entranced. But it's the second, compelling half that takes the show to the next level. It begins with the album's opener, "Go Do", an energy-fuelled, euphoric track of skittering instrumentation and percussive beats. The juxtaposition of "Boy Lilikoi" can only raise the euphoria, each musician contributing to the full sound arpeggiating piano, glockenspiel and rolling beats. It's on tracks like these that the influence of song arranger Nico Muhly, responsible for orchestrating albums by Björk, Bonnie "Prince" Billy and most recently Grizzly Bear's acclaimed Veckatimest, can be felt.

But nothing can prepare the rapt crowd for the finale, for which Jonsi re-emerges in a resplendent Native American headdress. The busy and crescendoing instrumentation of "Animal Arithmetic" – clattering beats and fast-paced vocals – builds up to "Grow Till Tall", in which a storm is projected onto the backdrop to the wall of sound created by the reverbing guitars, played frenetically against the stomping drums. It has a powerful effect on those in the prime spot, standing, who are buffeted by the lightning and pelting rain, fully immersed in – and almost part of – the performance. There is nobody in contemporary music quite like Jonsi.