It's a kaleidoscopic celebration of the single most seminal figure in the history of music, whether in works for one violin or for full chorus, soloists and orchestra. Alongside the concerts, lectures and discussions draw in a plethora of experts both musical and scientific, and the day culminates in a complete performance of the B Minor Mass. Gardiner's the man of the moment for Bach. He's fronting a new BBC documentary about the composer, which is being shown the day before the RAH bonanza, and his biography of Bach will be published in the autumn. Somewhere along the way he might have time to stop and celebrate his own 70th birthday, but don't count on it - he's a very busy person.
"It’s a celebration," says JEG. "Really, a celebration of the decade since we did the Bach cantata pilgrimage. Working through the cantatas in such a concentrated span led to me and the group reacquainting ourselves with the really big pieces – the B minor Mass, the two Passions, the Christmas oratorio, etc – and one’s whole perspective on those pieces has changed as a result of the cantatas. One sees them not as isolated peaks but as being part of the whole connective tissue of Bach’s church music. The cantatas are really the foundation of it all and the passions, the Mass and the oratorios are outcrops: they grew out of the cantatas.
"Our original plan was to do the St John Passion in the first half and the B minor Mass at the end. Unfortunately we couldn’t raise enough money to make that work, but what we have now is still an incredibly rich cross section from both ends of Bach’s life, in many different genres. The violin D minor partita, the cellos suites, the Goldberg Vairations, lots of organ pieces and the best of the motets. We have one of the earliest but also most magnificent of the cantatas that he wrote for Easter Day, and then the culmination is the B minor Mass."
Intriguingly, though, the Bach Marathon seems to be part of a growing trend in the classical music sphere towards grand-scale occasions packed with tempting talks and bonus treats.
They're all at it these days. The BBC Symphony Orchestra has scored major hits with its Total Immersion days devoted to contemporary composers such as Jonathan Harvey, Oliver Knussen and Toru Takemitsu. The Barbican is shortly to have a May Marathon weekend, curated by the hotshot young American composer Nico Muhly. Meanwhile BBC Radio 3 has taken to devoting a week or so of its schedules from time to time to the work of just one composer and, this year, a whole month to the Baroque era. And over at the Southbank Centre, the year-long festival The Rest is Noise is going further still, with weekend after weekend devoted to concerts, talks and films exploring 20th-century culture, setting the developing story of classical music in crucial context.
Gardiner has strong views on the necessity of this development. “I think it puts the spotlight on how limiting one-off concerts can be,” he says. “They can, of course, be fantastic. But when things are loosened up from that unit of a single event and related to a much wider experience, it allows people to get their shoulders underneath the surface of the water and relish what they find there – whether it’s in terms of variety of genres, a much broader approach towards a single composer or a phenomenon like The Rest is Noise. I think it shouldn’t be regarded as something freakish or exceptional. It should be welcomed as a corrective to the fixation on individual concerts.” He is convinced we’ll be seeing much more of this in future.
I reckon he's right. There’s a growing appetite for events at which we can learn a lot about one topic very, very quickly. It’s possible that pressures on people’s time and energy mean a one-day feast is more likely to draw a crowd than an ongoing course. But perhaps the crucial factor, certainly in the case of Gardiner’s Bach, is that it is more about celebration than didacticism. Everyone can take from it what they want: you can go to a single concert, or to the full gamut, plus lectures on the universality of this composer’s art by the likes of the science writer Anna Starkey and the jazz musician Julian Joseph.
“It’s a chance in a lifetime,” says Gardiner. He hopes his audience will take away “a sense of how unbelievably varied Bach’s oeuvre is and what a towering genius he is. One can perceive just from listening to his music what an enormous impact he had on subsequent musicians, both in classical music right up until our own times, but also in the worlds of jazz and of pop music. It can all be traced back to him.”
Bach Marathon, Royal Albert Hall, 1 April, 1pm onwards. Box office: 0845 401 5045