The trendy East London audience is standing around the bar in rapt silence. They are watching a man stroke a cactus. Later, someone else repeatedly chants the maxim “The best form of government is no government at all” and a woman puts on a giraffe mask. She also walks around the bar with a miniature truck tied to a piece of string. The other two performers are doing things too; one has an food blender, I think, and the other is playing with some electronics. The audience shuffles slightly, but only to clear a path for the miniature truck. Their attention is fixed.

George Barton performing Son of Tree by John Cage © Jeremy BalderstoneIt’s not like that sort of thing happens all the time, but it’s not completely unheard-of these days. Nonclassical have been putting on club nights, presenting the best in contemporary classical music in hip London locations, since 2004. And in fact they have played at The Macbeth, the bar in Hoxton where they were on 6 September, a number of times. As for all the bizarre goings-on, this is standard fare when performing John Cage’s Song Books, a bonkers recipe book of a composition which Lore Lixenberg, Gregory Rose and Robert Worby are making their own at the moment – whether in a bar, on CD or wherever else. (The cactus is required for another Cage work, Son of Tree, whose compositional cousin Branches received a recent outing at the Proms.) But what really continues to astonish me about the Nonclassical enterprise is just how incredibly cool these evenings are, despite (or more likely because of) their performing some of the most irredeemably eccentric music ever written.

I caught up with some of the Nonclassical team – founder Gabriel Prokofiev and Sam Mackay – at their East London offices the other day, and they were understandably pleased with how well their recent John Cage “100th birthday party” had gone. Though Nonclassical is an established fixture on the London scene now, it’s clear that each event is still carefully and individually fashioned, and they spoke with real enthusiasm about all of the performers – among them not just the trio doing Song Books but also pianist Leon Michener and keyboardist Kerry Yong, both of whom adapted Cage’s material in various intriguing ways. “The quality control is strict”, says Prokofiev, and he’s not kidding: though “quirky” doesn’t even begin to describe the musical content, the real quality of all of the performers ensures that the evening isn’t just a series of weird events; they’re enthralling weird events which make you want to listen.

Gregory Rose, Lore Lixenberg and a watermelon performing Song Books by John Cage © Jeremy BalderstoneThe Nonclassical team also have an impressive sense of focus regarding the type of act they work with. It was a little surprising, given his organisation’s name, to hear Prokofiev say “I think it is all contemporary classical” which they put on, though he does clarify that they’re “not afraid to take on other styles” too. Overall, I get the impression they simply have a slightly nonstandard conception of what should count as classical music: Prokofiev’s own music, after all, is very much open to influences from popular music. It isn’t what’s commonly called “crossover”, though: this is a genuine mixture of musical styles and traditions, meant neither ironically nor as a commercial venture. And while one key thing they take from popular music is a relaxed attitude to the concert format, they also play to what Prokofiev points out is one of classical music’s “biggest strengths”: the “level of musicianship”.

Gabriel Prokofiev, Richard Lannoy and Sam Mackay perform Radio Music by John Cage © Jeremy BalderstoneIn between the several short sets which take place at a typical club night, Prokofiev, Richard Lannoy or another Nonclassical DJ will take to the decks and provide something a bit less attention-grabbing. The crowd naturally take a step back, maybe get another drink, and mingle. There’s no awkwardness in switching between these sections of the evening, which points to an audience engaged with this format and appreciative of the relaxed atmosphere it allows for. Prokofiev suggests that a key concern is “giving people some autonomy” in how they act at concerts, and compares the experience to going round a contemporary art gallery: you can look at paintings for as much or as little time as you like, depending on how much you actually like each work. In the same way, if this particular piece of Cage or whatever else doesn’t grab you, you can wander off for a chat or a cigarette – and so people who want to talk tend to congregate at the back of the room, while those keener to hear everything closely listen at the front. “There is a big audience” for classical music presented in this way, Prokofiev insists – and it might well be an audience which isn’t especially enamoured with the traditional, rather austere customs which come with classical music.

Prokofiev says that the main motivation behind the Nonclassical enterprise is to increase “the availability” of contemporary classical music, “and therefore make it more accessible”. It’s certainly a noble aim, but I think it sells them slightly short. The Nonclassical events I’ve experienced have been radically unpatronising, and it’s never felt like an access scheme or an attempt to trick people into liking something uncool. Rather, it’s a presentation of genuinely edgy music in an environment that – unlike a traditional concert hall – has a little bit of edge to it as well. After all, if you’re looking for evenings out that push boundaries, as plenty of cool East London types are, then contemporary classical frequently blows the musical competition out of the water. And believe me, it’s a lot easier to take in Song Books with a beer in your hand.

The Sideris Quartet at a Nonclassical evening at The Macbeth in MayWhat’s next for Nonclassical? They’re keen to expand the reach of their club nights further, and seem optimistic to work with the Shoreditch club XOYO again – in maybe the closest they’ve come to “real” clubbing, their several evenings there so far have gone down a storm. And they briefly moot the possibility of a Wagner evening, too, to tie in with the 2013 bicentenary. I’m not entirely sure how that one would work, but it certainly sounds intriguing. Most of all, though, the team seem focused on continuing to deliver quality, regular evenings of contemporary classical music in trendy bars. This isn’t a gimmick; it’s a new approach to music.