Howard Goodall is that rarest of creatures in that he manages to combine being a high-brow classical music composer with a truly populist touch.

A much-lauded composer of choral music, his Eternal Light: A Requiem, which he recorded with the Christ Church Cathedral Choir, was nominated for Classic FM’s Hall of Fame this year and also won him the Composer of the Year title at the BPI Classical Brits Awards, staged last month.

Currently Classic FM’s composer in residence, he hosts a weekly show on Saturdays and has presented many television programmes about classical music.

Then again, this is also the man who brought us the music scores for Mr Bean films, TV comedy series Blackadder and The Vicar of Dibley and a raft of television commercials selling products as diverse as Walker’s Crisps and Pot Noodle.

The full scale of his achievements are too numerous to list here, spanning as they do pretty much the whole spectrum of choral music, stage musicals, film and TV scores.

Suffice to say, there are probably few people in Britain who have not heard at least one piece of his music, even though they may not realise it.

It comes as quite a shock to realise that, despite this impressive resumé, he is still only 51. He is also extremely unassuming.

During our conversation over coffee in a café in St Aldates, there are no soundbites or thoughtful pauses before he answers, and it is hard not to conclude that here is someone with nothing to hide and nothing to prove.

It is also clear this is no ruthless career type who meticulously plans his next step or hogs the limelight to look good.

Where some would worry about the unpredictability of his freelance lifestyle, he thrives on the spontaneity.

“I want to be doing lots of different things because it is so stimulating,” he explained.

“If I had only done one thing, I would be stir crazy. I deliberately take on things that are slightly outside my comfort zone to make myself think,” he added.

Composing comes as naturally to him as breathing, evidenced by his prodigious output.

“I hear the completed thing in my head, all the instruments, everything,” he explained.

His musical talent was obvious early on, when he was accepted aged eight as a chorister at New College and the same year composed his first piece of music.

He said: “I doubt what I wrote then was any good. I just assumed everybody could hear music in their head, I didn’t realise until much, much later that was not the case,” he pointed out.

While a pupil at Lord Williams’s school in Thame, he penned his first pop song, aged 14. “My parents were really into The Beatles,” he said. Then he went on to win a place to study music at Christ Church.

During his time there he struck up a friendship with the comedian Rowan Atkinson and Richard Curtis, who later became feted for his film and television scripts, including Four Weddings and A Funeral and The Vicar of Dibley.

After university, he worked with Atkinson on live stage shows and revues and began to make his name writing music for the popular television series Not the Nine O Clock News and Blackadder.

Far from ever suffering writers’ block, his problem is when a fully-formed melody enters his head he is often unable to write it down quickly enough.

“I have made myself train that part of the brain to retain it until later,” he said. “I end up scribbling away frantically in the strangest places and at the oddest times.”

He lights up when talking about his wife, Val, a classical music agent who lists Christ Church Cathedral Choir among her clients.

They met while both studying music at Oxford. She was a first year student when he was in his third, but their first encounter was less than promising.

“It was in a lecture theatre. I went over and asked if she minded if I sat next to her and she replied in a very offhand way ‘You can sit where you like.’ “Eventually, we did become very good friends but it took me the whole year to pluck up enough courage to ask her out and even then she said ‘no’,” Howard laughed ruefully.

They both went on to marry other people but, in what sounds like the plot of one of his friend Richard Curtis’s romantic film scripts, they met up again years later, when both divorced and fell for each other.

Given the breakneck pace of his life, he does not have much free time but when not working or composing, he enjoys reading or “just chilling with a nice glass of wine, watching TV, that sort of stuff”.

Looking suitably shame-faced, he added: “My wife would say I don’t take enough time off.”

He has two step daughters through his marriage to Val, the elder of whom is now a student at Oxford.

“They both love their music, although there was no pressure from us,” he said.

It was a low-key but telling example of the fame that success has brought when he apologetically asked me not to print their names as they receive emails from “people trying to get to me”.

Despite his success, he has never become blasé about performing in public.

“Whether it is public concerts, live television or making speeches, I find it incredibly nerve-wracking,” he said.

He is quite simply a man who loves music and wants as many others to share that as possible.

“I have always held the belief that music is something for everyone to enjoy and to participate in. It is a social justice thing.”

He was one of a raft of other luminaries, ranging from politicians to pop stars, chosen to spearhead the government’s Music Manifesto initiative, set up in 2004 to encourage children to take up learning an instrument at school.

Around the same time, the South Bank television arts show Musical Nation which he wrote and presented was a major turning point.

“It lit a fire in my belly,” he said. “The idea of changing lives through music is a passion for me. This is something we can do, it is not beyond us. Music is such a powerful force”

As a result, he was appointed as England’s first ever National Ambassador for Singing in 2007, his mission to get more primary school children warbling.

“Unlike the Jamie Oliver campaigns, where he is trying to persuade young people to do something they don’t want to, as in eat healthy food, primary school kids like singing,” he pointed out.

“If we can churn out 11-year-olds who have acquired the habit, they will probably hang onto it,” he added.

Ever one to rise to a challenge, he is now looking at how they might help secondary-school age kids.

“Never make a boy choose between choir and football practice and have boy-only as well as mixed choirs,” he observed sagely.

Although he and Val live in south west London and he works from a studio in Chelsea, they still have strong ties to Oxford and visit regularly.

“My family are all in Oxford and we both have lots of friends here,” he explained.

A few months ago he donated his manuscript of the theme music from the BBC comedy series The Vicar of Dibley to the Bodleian, a place that has fond memories for him.

“They have such an amazing collection of exhibits. When I was a student I found it so inspiring,” he said.

At the close of our meeting, he wound his scarf around his neck and picked up his briefcase which had music sheets sticking out of it at all angles.

Then he stepped out into the bustle of St Aldates and hurried off to meet his wife – an ordinary family man but one with a quite extraordinary talent for music.