Filed away in the darker recesses of my record collection are several dozen discs devoted to medieval instrumental music, more a sad fact than a boast. The same handful of pieces appear on most of them, presenting the same notes in something like the same order, but usually sounding uncannily different in almost every case. Only a few ancient instrumental pieces have survived in written form, and there are even fewer clues about how they were played. Would-be performers have welcomed the shortage of historical evidence as an open invitation to embroider simple tunes with wild counterpoints and to pick 'n' mix a medieval ensemble from the check- list of early instruments. Hey, Mr Tambourine Man, why not play along with the rebec, hurdy-gurdy, nakers, slide trumpet and sistrum?
While the bells-and-whistles approach has its attractions, especially for listeners new to the convoluted melodies of pre-Renaissance secular music, it can easily slip over the narrow line dividing artistic licence from kitsch. Stevie Wishart and her group Sinfonye prefer to interfere as little as possible with their source material, restricting their guesswork to interpretations of medieval theorists and of instruments depicted in religious art, while attempting to bring the music to life for thoroughly modern audiences. Their latest CD (on the Spanish Glossa label) explores the often bizarre untexted tunes to be found in a manuscript now housed in the British Library - works probably composed by musicians in the pay of the aristocratic rulers of Florence in the 1300s.
The disc, called Red Iris after the Florentine musicians' emblem, and inspired by their favourite istampite dance form - a genre so hypnotic in its complexity that one theorist believed it able "to divert the minds of the wealthy from perverse thoughts" - comes complete with an inter- active Mac and Windows 95 compatible programme, making it, or so it is claimed, the first ever medieval music CD-Rom. Those hoping for a magical history tour of trecento Tuscany, however, may feel short-changed by the "extra" components of the disc, though followers of Umberto Eco and his Travels in Hyperreality should have no problem deciphering its multi- layered, fragmentary and disparate signs and symbols.
Wishart worked closely with Sydney-based designer Kate Richards to create a medieval dreamscape, mixing everything from bird-song and bells to brightly coloured, blurred outlines of the British Library manuscript, Tuscan frescoes and echoes of Vespa mopeds at full throttle. The style owes more to Laurie Anderson installation art than to the world of CD- Rom infotainment, while its psychedelic screen backgrounds should appeal most readily to dedicated followers of the club scene.
"I'm involved as a composer with techno-trance type music," Wishart explains, "and I'd say there's a common link with drone-based medieval works and the idea of spaciousness in music. Like techno music, the istampite is non-developmental; that's what makes the medieval repertoire so different from the Baroque, and why I find it so attractive."
Wishart works hard to avoid delivering worthy but dull readings of medieval music, introducing elements of improvisation to her interpretations or exploring exotic tuning systems and strange instrumental colours.
Red Iris Interactive favours an anarchic, jigsaw-puzzle view of the Middle Ages, deconstructing the usual text-book reproductions of illuminated manuscripts and elaborate frescoes. "That's what I try to do in performance," says Wishart. "Yes, the playing should be historically aware, but without being safe or rose-tinted." She is suspicious of those ensembles that depend on period costumes and a dozen strategically placed candles to set the medieval mood. "It's fascinating to see how many people think of the past as comfortable, easy and safe, and how they don't want to be shocked by its sounds.
"In the medieval period, there is evidence not just for one type of violin, but for hundreds of different variations, each with its own peculiar timbre," explains Wishart, who herself plays medieval fiddle (as well as hurdy- gurdy) on the Red Iris disc. "If you play a simple monophonic line from a 14th-century instrumental piece on a modern violin, it sounds dull, which is not so if you use an instrument with a wider, less refined range of tone colours. It was this tonal complexity that attracted theorists of the time and which I want to get across today."
Medieval music treatises can hardly compete with the literary colour of contemporary tracts on mankind's damnation or the business of warfare, but several contain precious advice on the performance of instrumental works. Although musicologists have come to blows over the translation of certain obscure Latin technical terms, few have shown willing to interpret the handful of vague passages dealing with emotional responses to a well- formed work.
"I've had heated debates with academics on this point," recalls Wishart, "but there's no easy answer to the question of how an audience of Florentine nobles reacted on hearing an istampite. The limitations of the technology of medieval string instruments and their tuning affect how you play. But, for me, the expression of emotion comes directly from images formed in my mind from medieval descriptions of people dancing and hearing pieces being played in the street. Without those, I think performing this repertoire would become a very cerebral affair."
For the Red Iris disc, Wishart commissioned a reconstruction of a trecento fiddle as detailed in an altar-piece by Jacopo da Casentino, father of the musician Landini. The instrument's gut strings were set to the pungent tuning described around 1300 by the theorist Jerome of Moravia as suitable for "secular and all other kinds of songs, especially irregular ones", ideal for Wishart's transcriptions of the British Library istampite.
"There's a problem with modern players who pick up this repertoire and think it's `easy'. The pieces in the British Library manuscript would have been learnt the hard way, by rote, and performed on tricky instruments with difficult tunings. Because many musicians today regard this music as simple, they've assumed it to be their role to present it in a marvellous golden frame of speculative accompaniments. That's the exact opposite of how I see these pieces, which are thrilling monophonic compositions. The tendency has been to think of medieval instrumental music as music for dancing, and there are certain simple pieces in the manuscript that fit that bill. We've reasonably added percussion to those, but I played the more complex istampites on solo fiddle. I see those as the medieval precursors of Bach's unaccompanied violin works - innovative compositions that developed out of dance forms."
Wishart's passion for the art and music of the Middle Ages was aroused in her late teens on tour with a Celtic folk-rock group in northern Spain. The band's hurdy-gurdy player pointed out ancient carvings of his instrument in the cathedral of Santiago de Compostela, and Wishart was hooked. She later studied the iconography of medieval instruments with Christopher Page at Oxford, a scholar prepared to get down to the dirty business of actually performing early music (with his own ensemble, Gothic Voices).
"I was knocked out by the sound of these instruments in the band," recalls Wishart, "and soon became aware of the link with the past. As a composer, I wanted to put my own mark on the music I played, rather than follow the down and up bows of other players. That's just the type of freedom the medieval instrumental repertoire allows."
Red Iris, the CD, is on Glossa Nouvelle Vision (GCD 920701). Red Iris, the concert, is 8pm tomorrow, Union Chapel, Islington, London N1 (0171- 226 1686)