Eisenstadt was a garrison town with a large Jewish enclave, dominated by the Esterhazys' stone palace: this was where, for 30 winters, Haydn composed and performed like an indentured labourer. His ornate auditorium is as he left it, without central heating and with the same bare floorboards that gave it its crisp, clear acoustic.
Fertod was Prince Nicolaus Esterhazy's very successful shot at creating an eastern Versailles, with Gobelin tapestries, crystal halls, Italianate facades, and formal gardens. He'd built it in a swamp - ideal for duck- shoots, but also for mosquitoes. This was the gilded cage where Haydn and his band performed all summer, separated from their wives and families, and from which they were only released when the prince gave the word. In 1772 that word was unusually late in coming: the Farewell Symphony - in which the musicians snuff out their candles and one by one leave the stage - was Haydn's warning of mutiny in the ranks.
Haydn and his band worked in unusually sweet harmony, but linguistically they were anything but united. Hungarian was the language of the peasants, while the rich spoke German, and the aristocracy spoke French. Haydn, who had grown up among Hungarian and Croat peasants - he has even been claimed as a Croat - routinely operated in three languages at once. So when, today, one hears the Hungarian conductor Adam Fischer bark out commands in linguistic duplicate to the Austro-Hungarian Haydn Orchestra, it comes as no surprise.
Fischer and his band represent an extraordinary continuity. With half the players coming from Vienna and half from Budapest, the orchestra was formed with the explicit intention of preserving Central-European styles. They are currently three-quarters through a complete recording of all Haydn's 104 symphonies for the Nimbus label - a project commissioned by the record company's directors purely on the strength of the Haydnsaal's acoustic, and before they had even verified the orchestra's quality. But that quality would have won them the contract just as fast.
"When they first came together," says Fischer, "they couldn't speak each other's languages, but they already had a common style. It's a musical mother-tongue, a sort of dialect: a natural rubato that springs out of the score, a rustic quality that is hard to pin down in words, but very recognisable when you hear it. It's like good seasoning in food - only noticeable when it's missing."
But they don't perform on period instruments, and they don't make a fetish of authenticity. "We are not offering a museum re-creation of the sound of 200 years ago," he says. "For a start, nobody knows what that would be like. But you also have to take into account the way people's minds have changed. In an age without cars and machines, conceptions of loudness would have been very different. If we were to play at the original volume, it would be as disappointing as it is when you revisit the scenes from your childhood: what seemed enormous then is now disappointingly small. What counts, with music, is the effect on the listener. And to achieve the effects Haydn wanted, we must play louder than he would have dreamed of doing."
Since its formation 10 years ago, this part-time orchestra's personnel has remained remarkably constant, despite the stresses involved when one half are literally five times as well off as the other (such is the difference in salaries between Vienna and Budapest). And it now forms the basis for an annual Haydn festival at Eisenstadt, in which forgotten facets of the composer's uvre are held up for inspection.
One of Haydn's hobbies was writing operas for the shell-encrusted puppet theatre at Fertod: the highlight of this year's Haydn festival was a production of his rarely performed puppet opera Philemon and Baucis, or Jupiter's Journey to Earth. Its 18th-century premiere was accompanied by a banquet with fireworks: last week's performance was no less notable.
As presented by conductor Trevor Pinnock and director Christopher Leith, of the Little Angel Theatre, this ancient tale of virtue rewarded defies all categorisation: actors and singers share the stage with puppets and their minders, while the period-instrument English Concert play below. Ludwigsburg Theatre had originally planned to co-produce, but when their nerve went at the prospect of offering their auditorium to a "mere puppet show", they pulled out. This production may yet tour Britain: the South Bank are apparently interested, but have said they want to see what the critics say first. My verdict, for what it's worth, is that it's a show with great charm, marred by a creakiness that firm direction could easily eliminate.
The main problem is visual diffuseness. The drama comes at us in a bewildering variety of forms: with singers, actors, masked figures, puppets with Archaic Greek features, and puppets like doughboy blobs. The puppet-operators, meanwhile, work in full view like Japanese bunraku handlers; unlike the Japanese, however, they are not masked in black gauze. The lighting is so rudimentary that the eye wanders all over the place, rather than being directed where the drama requires.
After a while, however, one gets used to all this, and the humans begin to form interesting tableaux with their wooden miniatures. What at first seems inept, gradually becomes haunting. And the show winds to its conclusion via some magnificent - and endearingly low-tech - coups de theatre. Pinnock draws out the sunny generosity of Haydn's score, and his singers - notably the mezzo Jennifer Smith, and the soprano Jeni Bern, who is blessed with a voice of translucent purity - do him proud.
But the main appeal of this festival lies in the wheezes dreamed up by its young director, Walter Reicher. One of next year's, for example, is an "organ walk", whose participants will hear recitals on all the surviving organs that Haydn once played. There are seven of these in Eisenstadt alone: the town itself is a museum.
And Haydn's world is still progressively revealing itself. Reicher and his archivists scour the auction houses in London and New York for memorabilia, and regularly turn up new caches of letters and manuscripts; Haydn scholars in Cologne and Cornell University digest their import; each year new things are learnt. If this is museum culture, let's have more of it.
n For further information on the Haydn Festival call 02682 618660. The Austro-Hungarian Haydn Orchestra's series of the symphonies is released by NimbusReuse content