Empirical’s Pop-Up Jazz Lounge, Old Street Underground

“I can’t believe it. Free jazz in Old Street tube, how cool is that?” It’s a relief to hear this kind of thing from passersby, because Empirical’s attempt to bring jazz to the people, to reach new audiences and develop their music through an experimental, week-long residency in a London tube station, could so easily have gone wrong.

When I spoke to bassist Tom Farmer about the project, the MOBO-winners, due to release their fifth album, Connection, in March, seemed well aware of the risks. Commuters might hate it, or worse, keep their heads down and ignore it altogether. (“Don’t make eye contact!”) It seemed touch and go whether the band (jazz night owls to a man) would turn up to one of the performances, scheduled for 8am on a Tuesday, and there was also the distinct possibility that a jazz pop-up might tip Old Street over the edge. Could this postmodern cave of wonders – already crammed full of pop-ups selling pop art, kale juice, vegan energy bars, and spiralised fresh air – cope with jazz, or would Empirical bring about some kind of hipster singularity in which Silicon Roundabout disappears into its own Instagram account and a giant beard ultimately becomes the next Mayor of London?

Happily, it turns out that it can. In fact, on the evidence of Thursday night, the lounge is a roaring success: relaxed and welcoming, not edgy or pretentious, and consistently packed. It looks the part, a narrow space lit by filament lightbulbs and angle-poise lamps, with Empirical album art splashed across the walls. And the audience is as varied as the band had hoped: a few hardcore music fans (you can tell from the earnest nodding), men in suits, tech company types, shoppers and even a few kids. Not the usual jazz club crowd.

With all Farmer’s talk of publicity, outreach and audience questionnaires, my other worry after our conversation was that the music might be watered-down in the interests of accessibility, but there was no sign of that either. The four-piece were as adventurous and uncompromising as ever, stretching-out on episodic swingers, angular cross-rhythm-addled math-jazz and ambient ballads.

The dissonant melody of “Card Clash” set the tone, sliding into a solo for alto-player Nathaniel Facey, full of racing lines and aggressive squawks, with blurred chords and sudden stops by way of accompaniment. Illuminated by the ethereal glow of Lewis Wright’s vibes, “The Element of Truth” unfolded like time-lapse footage of a neon-lit cityscape, while “Stay the Course” was gutsy and rough-edged, juxtaposing stop-start interplay with passages of fluid hard-swinging.

“Anxiety Society” was nagging and on-edge, constantly looking over its shoulder, with a bustling feature for Wright, a solo for Facey full of bluesy alto whinnies and plenty of rhythmic risk-taking orchestrated by Farmer and drummer Shaney Forbes. “The Healer”, from 2013’s Tabula Rasa, was a highlight, dominated by heady vibes chords that shimmered as if from behind a heat haze. The heavy-hitting riffs of “One for ‘Bones’ Jones” were met with whoops of approval and “Conflict in our Time”, the finisher, saw all four men let rip as passing commuters craned their necks and crowded around the door.

Giving the jazz troglodyte a shove, getting out in the open and bringing it to new audiences can only be a good thing, it’s a thrill to see it done with such success.

• Empirical’s pop-up jazz lounge continues until Saturday 27 February 2015

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