The last time Philip Glass’ Music with Changing Parts was performed in London there were two 23-years-olds in the audience who thought it was, to say the least, pretty groovy. The duo – David Bowie and Brian Eno – would go on to cite Glass as major an influence on the trilogy of albums they produced together in the late 70s. (In a neat piece of symmetry, Glass later wrote three symphonies in response to the albums). After a 48-year hiatus the work has been performed again, this time at the Barbican, by the Philip Glass Ensemble – minus the eponymous composer who, sadly, was taken ill a few days before.

Although ostensibly meditative, I have always found Glass’s brand of minimalism to be profoundly cruel on two levels. Firstly to the performers – in the case of Music with Changing Parts the three keyboard players are required to churn out continuous semiquavers for almost 90 minutes, a task which Mick Rossi and Nelson Padgett accomplished on the night with aplomb – and secondly to an audience that is kept on the brink of catharsis for the same length of time, only to have it snatched away at the last minute. Your exit from Glass’s relentless, pulsating universe is as sudden as your entrance. But don’t let that put you off. Indeed, there is much to be gained from sitting through an hour and a half of slowly-shifting ostinati. Such music forces you to appreciate the commonplace; it rejects abstraction and confronts you with the beautiful, bare bones. It is also a sonic middle finger to the European avant-garde that Glass so despised. (He once called Boulez and his disciples “creeps who were trying to make everyone write this crazy, creepy music”).

With their dedication and near-mechanical accuracy the Philip Glass Ensemble exemplify this attitude. Their performance benefited from Glass’ recent rearrangement, which incorporates brass and choral sections, adding another layer of urgency to the New York haze. With each surge of white-note dissonance you feel a little closer to that ever-illusive denouement, and raucous, semi-improvised passages in the final third of the piece add real fire to the offering. Both the London Contemporary Orchestra and the Tiffin Chorus were immaculate in bringing this new orchestration to life. The latter in particular were a paragon of concentration and stamina, and conductor Valérie Saint-Agathe knew how to tease the very best out of them, building on the excellent work of their Director James Day. My primary criticism would be the overabundance of midrange in the audio mix. When you’re putting on a work that lasts 90 minutes – one comprised of mostly the same chord – it seems a shame not to give the different textures more definition. This could perhaps have been achieved with a little EQ wizardry, although I have noticed similar issues in previous amplified performances at the Barbican Hall, suggesting this may have been beyond the control of audio engineer Ryan Kelly.

I’m pleased that Music with Changing Parts has returned to London. Selling out one of the capital’s foremost concert halls is no mean feat, and the standing ovation that greeted the Philip Glass Ensemble at the close of their Herculean performance proves just how potent the music still is. Let us hope there were two more Brian Enos and David Bowies in the audience – who knows what magic it might have inspired.