There was just one problem. When Boulez said 'audience participation', he didn't mean handing over the means of musical production to the masses; what he meant was handing out little perforated slips with the programmes on which members of the public could submit musical queries for the maestro of modernism to answer from the podium. 'So he rejected my piece on the grounds that audiences would be stupid and would fool about with their kazoos in the other pieces too. Absolute rubbish,' Bedford protests, still peeved some 21 years later. 'That's never happened. He was just being too serious.'
And, despite the children's party atmosphere that can prevail in performances, With 100 Kazoos was just as serious an attempt to draw audiences into new music as Boulez's one-man Brains Trust. 'I thought that, if people were actually part of the piece, they'd pay more attention to the bits I'd written without them in. Which is what actually happens, and everybody claps everybody else at the end.'
Unlike many composers, Bedford has never forgotten his public and Kazoos was by no means his most extreme attempt to court them. In his 1970 The Garden of Love - the first classical piece (as opposed to Deep Purple-style symphonic rock) to combine orchestral and pop musicians, with a score that stipulated 'six beautiful girls for dancing and turning pages' alongside its array of classical instruments, electric guitars, organ, sax and drumkit - he even invited the audience to join in the final disco setting of William Blake. 'Oh, God] That was dreadfully sexist, thinking back on it,' he now says of those dancing girls. 'The idea was to make it more like a pop concert. But I withdraw that suggestion now.'
Not that Bedford has ever been a simple populist. More a maverick than a dedicated follower of fashion, his cross-over into rock was prompted less by an ear for the main trend than by the experience of having played in a band himself. 'If I'd been to India, I might have incorporated Indian things; if I'd been to Australia, I'd probably be writing for didgeridoos.' As it was, after studying in the early Sixties with Lennox Berkeley at the Royal Academy and with Luigi Nono in Venice, by 1969 Bedford had hit the road as keyboard player for the cult band, The Whole World, fronted by former Soft Machine lead guitarist Kevin Ayers and featuring Mike Oldfield on bass guitar. 'The only thing it really did,' he now says of his years as a rock star, 'was confirm to me that I quite liked the chord of E minor, because that's the only key in which Kevin could play. So it was a sort of reintroduction to the triad, where I'd been a sort of enfant terrible of the avant-garde up to that time.'
Something of the flavour of those days can now be recaptured on a new CD reissue of Bedford's 1972 album, Nurse's Song with Elephants, the original LP of which has attained cult status largely because of its guest appearances by Ayers, Oldfield and John Peel. Despite the odd embarrassment, Bedford stands by these early works. 'I look upon them with a certain tolerant affection for my younger self. I mean, you either have to adopt that attitude - or reject them totally]' That said, there is one track, Trona - written for the 1967 Cheltenham Festival in what he calls 'the approved harsh, discordant avant-garde style of the time' - for which he admits, with disarming honesty, that he was unable to provide a sleeve note 'because I have completely forgotten what the compositional ideas at work in the piece are'.
What all five tracks do display, however, is Bedford's fearlessness in tackling unlikely instrumental combinations: there are pieces for 10 acoustic guitars and six pianos, as well as two examples of his 'Music for Young Players' series - a mid-Sixties precursor of the current GCSE curriculum, offering one-sheet class- room introductions to a range of contemporary compositional styles - scored respectively for matched octets of recorders and melodicas and for 80 girls' voices accompanied by 30 'whirlies' (those serrated plastic pipes that produce a natural harmonic series when twirled about the head).
But then, as a jobbing composer of 30 years' standing, Bedford is used to writing whatever he's asked - 'one month a choral piece, the next a string quartet, then a piano piece. It's a nice variety'. Oddly, pop and film work apart (he's done arrangements for Frankie Goes to Hollywood, Billy Bragg and Enya, as well as for The Killing Fields, Meeting Venus and Orlando), wind band music has proved his biggest earner: he reckons he's made more in royalties from his five wind band pieces than from all his other 80-odd titles put together.
Always big in America, the wind band has become the surprise growth area in British amateur music-making over the past 10 years and Bedford managed to crash in at the start of the revival with Sun Paints Rainbows on the Vast Waves, a popular hit which he claims he wrote 'by mistake - because I didn't know what you were supposed to do'. The tradition - from Grainger, Holst and Vaughan Williams to the parent-pleasing Beatles medleys prevalent today - is to have a lot of doubling, with various instruments all playing the same tune. 'But in my piece, everybody gets a solo - they'd never had anything like that before.'
His latest contribution to the genre, although strictly it's for orchestral wind rather than wind band, is Susato Variations, a concerto-length showpiece - somewhat a la Paganini Rhapsody - to be premiered by David Owen Norris at the Leeds Centenary Festival of Wind Music on Friday.
The title is a little conservative by Bedford standards. 'I could have called it Raindrops Falling through the Forest, I suppose, but I've been more pedantic this time.' He admits, however, to a tendency for the fanciful. 'Some of my titles are a bit New Age before their time, but a lot of them come from poetry' - Garden of Love from Blake; Music for Albion Moonlight, That White and Radiant Legend and many others from Kenneth Patchen, a favourite American poet; Sun Paints . . . from Coleridge. 'I just thought it was a good way of identifying pieces. I mean, how many Symphonies are there? How many pieces called Sun Paints Rainbows on the Vast Waves? Sometimes, of course, I've gone over the top and the title's too long.' For example? 'What's my longest title? It's . . . Now, I'm not going to remember it . . .' And he agonises briefly before bursting out in triumph with: 'It's Pancakes, with Bacon, Maple Syrup, Butter, and the TV Weatherman.' Well, almost: in fact, he's got his 'butter' and 'bacon' mixed up; but then it was written 20- odd years ago, after the Canadian premiere of Kazoos. 'It's a stupid title. But I just had this vision when I wrote it of the Radio 3 announcer reading it out, in the old days, in a very plummy voice. And of course it never happened: it only first got performed in London this year.'
Bedford has another London first on Monday when the Spitalfields Festival premieres Touristen Dachau, a new 25-minute music-theatre piece for the soprano Jane Manning with a libretto, by Independent on Sunday music critic Michael White, inspired by a visit to the former Nazi concentration camp. Again, it marks something of a change in direction for the composer. 'A lot of my pieces, especially the poetry settings, are sort of generalised let's-all-be-nice-to-each-other sort of lyrics. This is more specific. It's a very emotional text, even violent at times, and the music mirrors the text.' During its course, the singer becomes various 'tourists' who have passed through Dachau - a Jewish girl, a male homosexual, a camp guard, a modern-day visitor. 'And it ends by asking if God was ever a tourist there and, if so, what he thought.'
'Touristen Dachau': Mon 7.30 Christ Church, Commercial St, London E1 (071-377 1362, 12.30-6.30pm only). 'Susato Variations': Fri 7.30 Leeds Town Hall (0532 455505). 'Nurse's Song with Elephants' is on Voiceprint (VP116CD)