Quick step by step

At 62, Davis clearly has the drive and energy of a man half his age. In the past season he has composed the music for a range of TV series, including Dance to the Music of Time for Channel 4 and Real Women for the BBC.

He's written the music for Cold War, the long-awaited follow-up to the BBC World at War mega series (as famous for Davis's music as for its extraordinary footage). He's been booked to write the music for Mike Leigh's next film, and the London Film Festival has commissioned him to provide a score for Erich von Stroheim's The Wedding March.

His conducting career, which began overnight in 1980, has grown arms and legs (and a wardrobe of multi-coloured jackets). The RSNO has booked him for two Prom concerts this summer. He's just returned from a Swiss tour with the Royal Liverpool Philharmonic. He has a series of tours each year with Dutch orchestras. He's conducting at an outdoor concert in Leeds.

And, as he observes with near-bemusement, suddenly his profile with London orchestras appears to be on the up. The London Philharmonic has taken him on for two performances a year, accompanying silent films at the Festival Hall, the Philharmonia has engaged him to conduct Pops-style touring concerts, and, at the end of this month, he will conduct a Royal Philharmonic Orchestra performance of Leonard Bernstein's Third Symphony, Khaddish.

As if all that wasn't enough, following the success of his Radio 2 series Carl Davis Classics, the BBC has commissioned him to produce another series. ''I admit I'm rather intoxicated with all of this conducting,'' he says, in the haven of his study - a vast, quiet, custom-built space embracing two pianos, one festooned with microphones, the other surrounded by the video and recording equipment that marks the engine room of Carl Davis the film composer.

''But I'm the kind of person that, if something starts, I'll just follow it. So I'm just going to let the conducting roll and see where it takes me.'' And that, basically, has been the philosophy of the tireless, talkative, bullishly enthusiastic American since he stormed into his parents' house at the tender age of seven and ordered them to sack his piano teacher, who had told the brash, questing, musically omnivorous youngster that he was too young to play Bach.

''I wanted everything, and I wanted it as fast as I could grab it.'' He was ''tolerated'' by his parents - second generation Americans descended from Russian-Polish immigrants - who encouraged him in his hungry search for musical experiences: amateur opera, piano playing, Gilbert and Sullivan, chamber music, lieder. At 18 he was signed up as pianist by the Robert Shaw Chorale to tour the States. Sitting about on 13-week tours led him to write music, which was played through by the singers and orchestra, awakening the instinct to compose.

Unceremoniously, he dumped performing, went back to college, studied composition, got himself a technique, and used it to write a ballet, incidental music for plays, and a commercial revue which transferred to off-Broadway.

Next (still 20 and still moving at the speed of light) he worked at Santa Fe Opera, then New York City Opera, and noticed that his collaborators were all heading, not for Hollywood, but for Europe. ''At that time, Hollywood, for someone on the east coast, seemed like the other side of the moon.''

So he got some money together and went to Europe, initially Copenhagen, and then, after a nomadic period, intrigued by the quality of films and theatrical work going on in Britain, headed to the UK, where his revue, Diversions, was staged at the Edinburgh Festival, transferring to London.

Ned Sherrin invited him to write the music for That Was The Week That Was. And that was the start that was. He moved, permanently, and began to stoke up the engine of his composing career, working behind the scenes with theatre companies, ballet companies, and in the studio.

Then, one night in 1980, his life took an abrupt turn. ''Suddenly I went public, and that one night changed everything.'' That night was the screening of Abel Gance's epic silent film Napoleon, with a five-hour score, composed and conducted live by Davis, to accompany the screening.

At the Napoleon premiere Jeremy Isaacs was so impressed that he came backstage and commissioned from Davis an entire series of scores for what was to become the groundbreaking Thames Silents series for Channel 4. ''Napoleon was absolutely traumatic. I had no idea how to go about constructing or organising such a score. It was like starting your mountain-climbing with Everest.''

The Thames Silents, still being shown all over the world, have passed into legend. At peak, he was producing two to three scores a year. ''I was always pretty fast, but what

I have now that I didn't in 1980 is a methodology; I've built a step-by-step way of doing it so that I can arrive on the platform, able to control the score, and be in sync with the film.''

This weekend, Davis opens a short season of matinee performances of three silent movies, each demonstrating the work of one of the three great comic geniuses of the genre, each with a different Davis score. Harold Lloyd's The Freshman is first off this Sunday, accompanied by a twenties-style jazz score (played by Dutch outfit, the Willem Breuker Kollektiev Band, who will preface the film with a half-hour session of their own music).

Charlie Chaplin's double-bill, The Kid and Idle Class, with Chaplin's own music painstakingly reconstructed and extended by Davis, are lush scores that will be played by the RSNO at the second show in June.

And, in the autumn, Buster Keaton's Our Hospitality will feature Davis's Schubertian score played by an expanded BT Scottish Ensemble. ''Each of the three films is a masterpiece, and it's very rare to put these three giants together. It's also the first time we've done a matinee; so I hope families and children will come and get the impact of these on the big screen with live music.''

n Harold Lloyd's The Freshman: Glasgow Royal Concert Hall, Sunday 3pm.