Lord of the strings

More than 250 years after his death, Antonio Stradivari's violins and cellos are the best in the world. On song and in the right hands they are magnificent, projecting their glorious tone to the back of the largest concert hall, and responding immediately to their player's every change of style, pitch, volume - even mood.

In a recent season at London's Royal Festival Hall, four of the five soloists played Strads (the inevitable abbreviation). They are the ultimate rebuke to the arrogance of the modern age: science does not have all the answers; renaissance technology still cannot be bettered.

The Messiah is probably the most famous Stradivarius, celebrated for its almost impeccable condition. Its varnish is as flawless as when Stradivari applied the last drops in 1716. Such perfection, however, comes at a price: the Messiah has hardly been used; there are no famous performances in its history. If someone tuned it up now it would not sound terribly good - for reasons that are still not fully understood, violins have to be "played in" over several months or even years to develop their full tone. Nevertheless, its story is fascinating.

The first notable point in the Messiah's biography is that it was unsold at its maker's death. Although by the end of his life Stradivari had accumulated a substantial stock of unsold instruments, almost all of them were later - and, arguably, lesser - examples of his work.

The Messiah is from his "golden period", the first two decades of the 18th century, when it was all Stradivari could do to meet demand. Why the Messiah did not join the stream of instruments leaving his workshop is a mystery, and it was part of the legacy inherited by his eldest son and principal helper, Francesco. He only survived a few more years, and left the violin, with 100 others, to his youngest brother, Paolo, who liquidated his inheritance over a period of 30 years, selling the Messiah to a young nobleman, Count Cozio di Salabue, shortly before his own death in 1776.

In the late 1820s, Count Cozio sold the violin to Luigi Tarisio, the son of an Italian peasant. Despite his humble origins, Tarisio would come to own more Strads than anyone apart from their maker. He had an obsession for them, and he fed it by travelling through Italy, playing the violin to support himself, and sniffing out treasures.

On arrival in a village he would ingratiate himself with the locals to find out if anyone owned a violin, or he might visit monasteries and other likely prospects, offering to repair their instruments. Armed with information he could gauge the situation, perhaps simply buying cheap or, more subtly, offering new violins for old. Even if this resulted in no purchase, knowledge was still useful to him; and Tarisio became both expert and collector.

He had the advantage, as later dealers noted ruefully, of coming across violins with their original labels; so he was able to build an accurate picture of different violin-makers' work. Those who bought from him were not always so lucky: he does not seem to have been averse to increasing an instrument's value with a little judicious forgery.

Even those who realised what he did, however, did not think of him as crooked. If he had been seeking material gain, he would surely have lived a more luxurious lifestyle. In the words of Charles Reade, the Victorian novelist and occasional violin dealer: "The man's whole soul was devoted to violins."

Whatever Tarisio's motives, we should be grateful to him. Over 600 Strads still exist, more than half their maker's output. It's an impressive survival rate for such fragile objects, and we owe it to Tarisio, who recognised their value relatively early in their lives.

Tarisio was more than a dealer, however: he hoarded violins. The best went straight into his collection, and none was better than the violin he had bought from Count Cozio, the Messiah. He would taunt other connoisseurs with its existence. It was on one such occasion that the violinist Jean-Delphin Alard said: "Then your violin is like the Messiah: one always expects him but he never appears." The name would stick.

Alard's father-in-law, the great violin-dealer, maker and copyist Jean-Baptiste Vuillaume, would eventually bring the Messiah into public view, but he had to wait for Tarisio to die first. The moment Vuillaume heard the news he scraped together as much money as he could and caught a train for Italy.

For the next 20 years he would regale listeners with the story of his arrival at Tarisio's farm. The dead man's relatives were assembled there "with every appearance of the most sordid poverty". Vuillaume's enquiry for instruments was met with some disdain - most of the junk was in Milan, where Tarisio had died, surrounded by his collection, but half a dozen violins were at the farm.

Guided by Tarisio's sister, Vuillaume bent down to a rickety piece of furniture. Inside he found five masterpieces, but it was the contents of the last violin case that took his breath away. Tarisio had been telling the truth: there was the Messiah, as perfect as the day it was hung up to dry.

Vuillaume bought 150 instruments, including about two dozen Strads, from Tarisio's heirs. Over the next few years he sold on almost his entire purchase at huge profit, but kept the Messiah. Only Vuillaume's own death in 1875 broke the bond.

There were whispers that this was an enchanted violin that kept its owners in its thrall. Various changes of ownership followed, but by the late 1920s the Messiah was in the hands of the Hill brothers, whose London dealership could eventually claim to have seen more Strads than Tarisio. They were determined that the Messiah should not leave the UK, and that it should not fall into the hands of anyone who wanted to do something so sacrilegious as play it. Refusing a blank cheque from Henry Ford, they placed the violin in Oxford's Ashmolean Museum.

There the story might have ended - the Messiah still hangs in the Ashmolean - but for the sting in the tail. In the late 1990s a researcher with doubts about the violin's authenticity sent photographs of its front to a dendrochronologist. He measured widths of tree rings as they occurred in the wood's grain, compared them to an established reference series, and appeared to show that the relevant tree could not have been cut down before 1738, one year after Stradivari's death.

The implications were enormous, and not just for the Messiah. If the most famous Stradivarius in the world were fake, how could any attribution to Stradivari be trusted? The labels in violins have been untrustworthy since the days of Tarisio. Violins can only be attributed through stylistic judgments, and it is the dealers who make them. The certificates they issue carry the weight when it comes to a violin's authenticity, and therefore value.

With their reputations at risk, violin dealers closed ranks. They commissioned further dendrochronology that dated the Messiah's wood back to 1682, but there was controversy over the methodology. A scandal seemed about to break. All subsequent work, however, has verified the 1682 date. Moreover, there is a good cross-match between the wood in the Messiah and that in other Strads. Everything about the violin is consistent with its label, "Antonius Stradivarius Cremonensis Faciebat Anno 1716".

There remains the question of Stradivari's resistance to imitation. Vuillaume is counted among the best violin-makers of the 19th century. He took Strads apart so that he could reproduce every possible measurement, placed the Messiah and his copies of it side-by-side so visitors could guess which was which, and advertised that his violins would be as good as Stradivari's "after a little use". Yet nobody would now believe that claim. A compelling reason for refusing to attribute the Messiah to Vuillaume is that it is simply too good to be his work.

These days, we can recognise the mistakes in Vuillaume's techniques; the best modern violin-makers do not repeat them. Many argue, in fact, that some of the instruments produced in the past 20 or 30 years do match Stradivari's. All they need is time to mature. Yet it's this need for a violin's wood to age - for perhaps 50 or 100 years - that shows the futility of attempts to imitate Stradivari.

Perhaps his genius really is inimitable. But the violins Stradivari made are not perfect; they can be moody; they have off-days. Modern violin-makers benefit from the knowledge brought by history and science. It may need another genius, but surely one day someone will produce instruments that not only match Stradivari's, they supersede them.

· Toby Faber's book, Stradivarius: Five Violins, One Cello and a Genius is published by Macmillan, price £16.99.To order a copy for £14.99 plus p&p call the Guardian Book Service on 0870 836 0875.