"Good evening. You are nearing the end of your journey. Dress in DARK colours and meet on The Oval... at 19:50..."

This was the text that greeted me when I followed the link that the London Contemporary Orchestra emailed to all ticket holders ahead of their concert on Thursday 3 October. I did, as requested, dress in dark colors, and arrived at "The Oval", an oval-shaped car park in a still pre-gentrified corner of east London. In lieu of a ticket, I was handed a black pill-like capsule with "ANTIMATTER" written on it in white letters. (I eventually discovered that the capsule contained a tiny, rolled-up program of the evening's events.) I went and stood in the car park with a gradually increasing throng of curious and somewhat confused fellow concertgoers.

Without warning, there was a sudden burst of sound and light up on the roof of the warehouse building in front of us. A clarinettist (Harry Cameron-Penny) stood on the roof, illuminated only by small lights attached to his head, elbows, knees, and the clarinet bell, and wailed out a brief fanfare of sorts, punctuated by shrieks and multiphonics.

Thus began the third and final instalment in the LCO's Imagined Occasions series, which are, according to their website, "site-responsive, immersive performances" that "seek to engage the audience in a participatory narrative, in which the audience are observers, creators, protagonists and the observed". It was certainly an apt description of what followed. After the brief clarinet introduction, the folks who had been instructed to dress in "light" colours were led into one door, while my fellow dark-colour folk and I were led in another door. It is not entirely clear to me what happened to the "light" people for the rest of the show's first half. I think they heard the same music we did, but in a different setting or in a different order. But for all I know they might have spent the first half of the concert at a Mahler symphony or a dance party.

We "dark" folks were led through a door, up a few flights of stairs, and into a large, open room with a high triangular ceiling and windows all along one side that looked out on east London. Violinist Daniel Pioro was already playing by the time I got there, moving gracefully through the space, spinning out a lyrical and contemplative solo improvisation. I thought I saw a lost audience member stuck outside, looking in through the windows, but it eventually became clear that this was in fact a dancer from the Nutshell Dance Company, who was part of the performance.

This improvisation was followed by an electronic composition, Claude Vivier's Variation I, an array of burbling crunchy sounds of varying pitch and intensity. Four dancers appeared outside the windows, at times doing their own thing, at times in tightly synchronized motions, convincingly choreographed by Mari Frogner. The combination of electronics and dancers on the outside looking in created an eerie effect.

When the piece concluded, we were led through a door and down a flight of stairs to a garage, for another electronic piece, Henri Pousseur's Seismagramme I–II. The soundworld of this piece was an intriguing mixture of various distorted bell-like sounds. As it progressed, dancers emerged seamlessly from amongst the tightly packed audience. They interacted with one another, but also with various audience members, silently guiding their chosen partners to mimic their motions. Some audience members accommodatingly played along, while others just watched and declined to engage.

From here we were led upstairs again, this time to a different room which looked a bit like an indoor patio where drinks might be served. A shirtless, shoeless, and generally rather dishevelled-looking man (percussionist Adam Clifford) sat on a platform with his hands over his face. He suddenly burst into gasping vocalizations, and with them began Vinko Globokar's ?Corporel. He worked his way through a large range of vocal sounds, from grunts and gasps to teeth-clicks, a kiss, a yawn, wordless singing, and snoring. He also hit and slapped himself in numerous different ways to create different types of body percussion. It was all delivered with a mixture of curiosity and extreme agitation, like some distant ancestor of homo sapiens discovering all of these sounds for the very first time. There was one moment in the whole piece where all these sounds actually coalesced into words, as he shouted the text "The history of mankind is a long succession of synonyms for the same word. It is our duty to disprove this." His last act was a sudden simulated self-stabbing in the stomach, with a gut-wrenching cry to go along with it. He collapsed, the lights went out, and he ran out the door and down the stairs. Many in the audience chuckled nervously. It was unclear, to me at least, whether this piece was meant to be deadly serious or humorously absurd. Based on the few other Globokar works I've seen, I would guess both. In either case, it was an admirably intense and committed performance from Clifford.

The lights came up, and it turned out that we were, in fact, in an indoor patio with a bar: it was the interval, and drinks were for sale.

The second half of the show was much closer to a traditional concert format. We were back in that first large room, where we were reunited with our "light" comrades. The performances alternated between a stage on one side of the room and a balcony on the other. George Benjamin's Three Miniatures for Solo Violin, beautifully played by Pioro, led things off. It was followed by Jonathan Harvey's Ricercare una Melodia for solo trumpet and electronic delay, played with great panache by David Geoghegan. Next came the première of Alastair Putt's dark, ponderous Madragula, for a large, wind-heavy chamber ensemble. Thomas Adès' spritely Catch followed, for violin, cello, piano, and roaming clarinetist, and the concert closed with a satisfyingly raucous rendition of Edgard Varèse's classic Octandre, led by Robert Ames' clear and energetic conducting.

So, what to make of it all? Did all of the extra-musical goings-on – the dancers, the pre-concert gathering outside, the "anti-matter" program pill, the moving between different spaces – make for a compelling theatrical experience? In some ways, yes. The dancers were a wonderful touch, and the ways in which they were alternately excluded from the performance space (when they were outside the windows looking in) and emerged from within the audience was intriguing and thought-provoking. One of the evening's most effectively theatrical moments was at the end of the interval. The "dark" half of the audience was led back to the main space by way of the balcony where the dancers had danced. We could see the "light" half inside, through the windows, but we couldn't join them yet. We were in a sort of limbo. As we gazed in the windows at the "light" audience watching us watching them, it created this very odd sensation of simultaneously watching and being watched, of being both audience and performer. It was both intriguing and quite disconcerting.

On the other hand, in some ways it was all rather distracting. There was so much to take in and so much to re-adjust to for each piece, that it was difficult to really focus on the music. Most of us spend our days multitasking and perpetually distracted by numerous different stimuli. It can really be a relief, I realized, to go to a space where you can sit quietly and focus on one thing, as you can in the traditional concert hall format.

Perhaps what was missing was the sense of an overarching theme or narrative. I understood that they were playing with and questioning the audience–performer dichotomy, and much of this was effective and thought-provoking. But the purpose and meaning of the different spaces was less clear, as was the color division of the audience, the "anti-matter" pill program, and the huge difference between the two halves of the concert. Not that art has to add up to an obvious meaning or point, but I think the experience would have been more powerful if it had been more clearly focused.

That said, I do think it was a thoroughly worthwhile experiment, and I appreciate LCO's boldness and willingness to take some risks. I hope they will continue to make more experiments along these lines, but I also hope that they spend some time afterward assessing what worked well, what didn't work so well, and what could be extended and expanded to make something even more spectacular. They're definitely onto something, but I'm not sure they quite know what that something is yet.

Imagined Occasions, at Oval Space

London Contemporary Orchestra presents a creative re-imaging of the concert experience in the final instalment of its Imagined Occasions series at the Oval Space in East London. They're definitely onto something...