Tonight, the Barbican is a vortex. There's an indescribable chasm between my body and my conscience; between bouts of frenzied applause and a brief nicotine-fuelled interval, there is no one in this room other than me, Joanna Newsom and the distant faces of an orchestra.

From the moment she utters the opening call, "The meadowlark and the chim-choo-ree," an entire audience is eating from the palm of her delicate, yet mesmerising hands. Not a word is uttered between two members of the audience and the only time that eyes wander from the stage is to look upon the nearest and dearest in amazement and disbelief.

For the first hour, we're treated to a full performance of Newsom's most recent LP, Ys, replete with backing from the London Symphony Orchestra. Even the premise of this event was more exciting that 1,000 nights in the Barfly; in practice, it is the most glorious musical experience of my lifetime. Bar none.

Every nuance, every glorious deviation, lyric and quirk is captured in energetic yet considered glory. Van Dyke Parks' arrangements resonate in a way that recorded mediums could never replicate; the soaring strings and unpredictable twists are showcased in an aural blanket that wraps you up, keeps you warm and somehow justifies the existence of humanity.

These aren't the utterings of a devout follower of Joanna. In fact, before Ys she'd failed to make an impression on me whatsoever. Tonight though, inside one of the capital's most salubrious settings, all other music is rendered limp and directionless.

Beyond all praise and heaped hyperbole, however, lies a simple fact: Joanna Newsom is one of a woefully rare breed. There is positively no one else producing music that sound like this in the world today. A voice that polarises yet enslaves minds across the world; a songwriter who effortlessly dictates moods, conducts life-changing sermons and commits them to tape. A lyricist peerless in her field and a storyteller who can send even the most detached individuals into worlds of her own making.

An encore includes a fabulous new song, highlights of her The Milk-Eyed Mender debut and a Robert Burns poem set to music in the form of 'Ca' The Yowes Tae The Knowes'.

Days after, there will be little point in listening to anything else. It wouldn't be fair. For tonight, Joanna Newsom is the most important musician in the world.