05/06/2013 13:38 BST | Updated 05/08/2013 06:12 BST

Introducing the Orchestra With No Conductor

Imagine you're playing Pictionary. To your slight horror, the word that comes up is 'orchestra'. Where do you start? With so many instruments to depict, the easiest thing to do, unquestionably, is to start with something intrinsic and central to all orchestras: the conductor.

But what if an orchestra had no conductor? What would happen? Would the diverse tribes that comprise the ensemble play as normal, or would there be anarchy, bedlam and discontent, like a nation without its prime minister? (Okay, let's not dwell on that analogy.)

This Sunday, you can find out what happens as conductorless orchestra Spira Mirabilis comes to town. I first saw them two years ago and now wouldn't miss their concerts for the world. To be fair, the members of Spira haven't ejected their conductor in a revolutionary coup: drawing players from Europe's finest orchestras, they all work with and rely upon conductors week-in week-out. But for once they wondered whether it might reawaken some of their own innate creativity and responsibility to attempt putting a piece together on their own.

Thankfully this isn't a 100-strong symphony orchestra, it's a relatively small group - just 23 on their visit to London's Southbank Centre this Sunday afternoon - but that's surely still enough to cause havoc. Imagine the rehearsals. Who decides which bits to focus on, what changes to make, when to break for tea?

Having seen Spira Mirabilis in concert, and in rehearsal, I can't quite tell you how the magic happens, but it does. Somehow, instead of relying on someone else to take the lead, they all do it. Nobody is a passenger. Everyone's driving. Which doesn't mean it's a swarm of egos either. Watching them, you'll notice their eyes are seldom on the sheet music in front of them. They are all constantly watching each other. And listening to each other too.

Somehow, this hyper-reliance on the senses makes their music seem spectacularly alive. I've seen them perform two Beethoven symphonies and both times these classic works, over two hundred years old, have seemed brand new, every note considered afresh by every player.

The practice isn't new. For a long time, there were no conductors. This only changed in the 17th century when composers like Jean-Baptiste Lully felt compelled to stand in front of the ensemble and keep time by tapping a heavy rod against the floor (the familiar baton took its place after Lully accidentally impaled his foot with said rod, developed gangrene and died).

Nowadays, some ensembles often perform without a conductor, the lead violin demonstrably directing the proceedings instead. But Spira goes one step further: the lead violin remains just one voice in the mix, and the cellos or oboes are just as likely to take charge at any moment if they collectively feel this best serves the music. It wouldn't work with any piece, and Spira has the luxury of retreating to an idyllic Italian hilltown to spend hours finessing one work at a time, but the effect is still remarkable.

This week their choice of music is particularly exciting. They will perform Richard Strauss' extraordinary Metamorphosen, written in 1945. It's a tough piece that requires serious marshalling: my own orchestra Southbank Sinfonia has just conquered it with the help of legendary conductor Vladimir Ashkenazy. It's written for 23 solo string players, a myriad voices each following their own path, striving for unity yet fractured by the atrocity of the Second World War.

I can't quite imagine it without a conductor, but I'll be right there in the stalls to see it done. Strauss wrote the piece as a means of trying to find some consolation, some humanity, in the wake of devastating events. Here we are reminded that this is often what orchestras represent: they are a gathering of individuals, each with their own story, their own voice and views, yet together they meld their differences into a united strength, beauty and accord. Aren't these great values for us all to live by?

Even with a conductor, this is apparent, though in Spira Mirabilis you see the prospect at its purest: it's all for one and one for all.