Theatre: If music be the food of drama . . .: Only one man at the RSC has worked on all Shakespeare's plays. Jenny Gilbert met him

HOW'S THIS for a job description: composer, well-read, able to adopt any musical style yet bursting with beautiful, innovative ideas, required for low-profile post in the country. Must be willing to have said innovative ideas rejected or reworked by non-musical superiors, for best efforts to go unmentioned in the press, and to be consigned to oblivion once they have served their purpose. No major egos need apply.

There was never a more suitable candidate than Guy Woolfenden, but it is still remarkable that the Head of Music at the RSC has held that job for more than 30 years. He has witnessed the birth of the Barbican and the Swan, and nurtured the musical life of around 900 productions, writing scores for 150. Now he has completed the Shakespeare canon: all 37 (arguably 38) plays. For years, one seemed to elude him: that disregarded early play, Two Gentlemen of Verona. It transferred to the Barbican last week in a revelatory production featuring a chanteuse, a dog, and a stack of hummable tunes.

Two Gents, says Woolfenden, is a fine example of how music can salvage a play. The text gives us 'a vapid comedy about four intellectually sub-normal teenagers', with a denouement so implausible as to floor the most skilful direction. David Thacker has given it a Jeevesian setting and intercut the inconsequent romancings with numbers from an onstage band. Thus the great lyricists of the 1930s (Porter, Gershwin, Berlin) rub shoulders with that great lyricist of the 1590s. 'Who is Sylvia?', the one song lyric Shakespeare wrote for the play, was set by Woolfenden as a crooner's serenade. In the process he discovered that 'Shakespeare hadn't a clue how to write a Thirties song. He didn't give us a middle- eight.' Some judicious tinkering with the lines put him straight on that.

Woolfenden could never be called a purist. Given a free hand, like a good director, he starts from what he thinks Shakespeare wanted. 'I don't mean let's have a viol and a bit of thatched cottage music. I mean what he wants intellectually. What the play needs.'

Often the director arrives with a precise (if impractical) idea of how he wants the production to sound. Woolfenden recalls a famous Macbeth where Peter Hall wanted to create a society so primitive that metal was rare. Only the odd Thane was to have a sword, the rest wooden spikes. 'He said to me: 'I've created these restrictions on stage. The same applies to the music. No metal trumpets.' ' Woolfenden disappeared into the RSC workshop and emerged several weeks later with a set of non- metal trumpets, based on animal horns

and rendered in fibreglass. The sound was what was wanted: frighteningly primitive. It only remained for the band to learn to play them. Enter Guy Woolfenden, former professional horn player. A man of many parts.

Probably his greatest contribution has been to drag the musicians out from under the stage and on to it - in costume, in character, with appropriate-looking instruments. 'Live music is not enough,' he insists, 'it must be seen to be live' - a principle which extends to refusing to fake it when musical skills are required of actors. Two famous RSC Ophelias, Glenda Jackson and Janet Suzman, were put through their paces on the lute; Helen Mirren, in The Roaring Girl, scraped away at the viola da gamba after seven weeks' tuition - 'but that was pushing it a bit,' Woolfenden later admitted.

Peter Hall has championed this softly spoken polymath since the early Sixties, when they collaborated on the spectacular Wars of the Roses, still a benchmark in theatre history. It was the young Hall who gave Woolfenden the RSC job, at the age of 25. 'He was first suggested to me as a conductor,' Hall recalls, 'but I soon saw that this man had a rare theatrical instinct. He takes an interest in the design, the rehearsals, and conceives his score accordingly. Which is not the same as bringing along something with 'Woolfenden' written all over it.'

And there's the rub. While composers used to the stylistic freedom of concert commissions might chafe under the eclectic demands of theatre, Woolfenden seems liberated by them. 'I hope I'm a good theatre hack,' he says candidly. He has no ambition 'to write an unperformed and unperformable British symphony'.

It's not the loss of personal signature so much as what they do to your lovely score. For a film, the composer works to a video of the completed cut, and musical sequences can be timed to a hundredth of a second. In the theatre no one knows how long each scene change will be until a week or so before the dress rehearsal. Woolfenden is famous in the company for his ability to turn out new cues, fully orchestrated, from a seat in the darkened stalls. There is pragmatism in this last-minute madness. 'If you've written it all six weeks ahead, you then find nothing fits and you've got to cut, even before the director gets his scissors out. It can still hurt, even after 30 years.'

'Two Gentlemen': Barbican (071-638 8891).

(Photograph omitted)