GERALD MOORE WAS ONCE asked whether, in the course of his long and distinguished career as accompanist to some of the greatest singers of the 20th century, he had ever given any thought to becoming a pianist. Moore's response is not documented, but had he delivered one, he would most certainly have put the enquirer right on one thing: the art of the piano accompanist is exactly that - an art in itself.
And few come more artful these days than Malcolm Martineau, whose annual appearances at the Edinburgh International Festival are more regular than most, but whose visibility - unless you're specifically looking out for him - can easily be masked by the fact that he has chosen to follow the same career route as Moore.
Martineau's love for the Festival is as much personal as professional. He was born and educated in Edinburgh, and his father - who died when he was only nine - was a prominent clergyman in the capital. His mother is the notable pianist Hester Dickson, who is now in her eighties, but still highly active as an accompanist and teacher at Glasgow's RSAMD.
Listening as a youngster to the regular musical collaboration between his mother and her late sister, the cellist, Joan Dickson, rubbed off on Martineau. "I've always loved the idea of collaboration in music. When I reached the semi-finals of the first ever BBC Young Musician of the Year competition in 1977, a lot of solo work came out of that," he recalls. "But I knew that solo playing wasn't really my bag, and when I went to Cambridge, I did lots of chamber music. I'm not the solitary type."
Now in his late forties and based in London, he is one of the most accomplished accompanists around today, on first-call terms with the likes of Bryn Terfel, Simon Keenlyside, Christopher Maltman, even Simon Rattle's other half, the Czech mezzo soprano Magdalena Kozena. He tours and records regularly with many of them.
There is still, says Martineau, a lingering perception that the accompanist plays second fiddle, especially when a singer is in the limelight. "There have been several occasions when someone has asked me if I went to 'that wonderful song recital last week at the Wigmore Hall', and I've had to answer: 'yes, I was actually playing'. The fact is, the audience come to see the singer!"
So will he go unnoticed in his two Festival appearances next week at the Queen's Hall? First up on Monday he will perform with the baritone Simon Keenlyside in a programme that includes Benjamin Britten's Songs and Proverbs of William Blake. Then, on Thursday, he will accompany the soprano Anne Schwanewilms in a potentially ravishing coupling of songs by Richard Strauss and Mahler.
"Anne is the one that sang [Strauss's] Ariadne in the dress that didn't fit the other soprano," he says, referring mischievously to the notorious incident in 2004 when London's Royal Opera House sacked its original soprano, Deborah Voigt, reportedly because she was overweight.
The answer to the above question, though, is no. It's not Martineau's style to fade into the distance. Indeed, he immerses himself completely in a performance, quite visibly at times. Watch his eyes and his gestures. They are a reflective interpretation of what the singer is singing.
"As an accompanist, you must have an ear for colour, for storytelling," he explains. "Benjamin Britten was my favourite accompanist of all time. He had a composer's ear for colour. He could achieve an amazing range of dynamics, even at the softest end of the spectrum. That is where accompanying becomes such a different art from the solo role."
But it's important, too, he says, to know how a singer works - both technically and psychologically. He has made his career out of doing so. "I was trained also as a singer," he says. "After Cambridge, I took joint first studies in singing and piano at the Royal Academy of Music. That's paid off. I tell my own accompanist students at the RAM to get singing lessons. It's important to know what breathing [as a singer] feels like." Learning languages, too, has equipped him well for the role. "I'm no linguistic high-flyer, but I do understand French and German poetry."
Seasoned singers have grown to depend on Martineau's instinctive artistry. Younger ones look to him for advice. Thomas Quasthoff, indeed, calls him a "psychic". "He once said to me after a recital: 'you knew what I was going to do before I did it'," recalls Martineau. "The truth is, as an accompanist you have to second-guess what the singer is about to do. Half the time you get it right."
If anything singles Martineau out as much more than a jobbing accompanist it is the entrepreneurial spirit that has led him to lead, and often instigate, extended projects of his own, particularly with singers.
Festival aficionados will recall some years ago the extraordinary series that encompassed the entire Lieder output of Hugo Wolf.
"It was essentially [Festival associate director] James Waters's baby, but I became immersed in it and it became an amazing thing to do," he says. "I try to do series here and there, to encourage singers to learn new repertoire."
He is currently exploring rarely heard Russian songs by Rimsky- Korsakov and Glinka, and later ones from the 1950s, with Susan Bullock. He is also putting together a series centred on the songs of Poulenc, presented in the context of their own time. "Aside from Schubert and Wolf, I love the French repertoire," he says.
Most of all, though, he is relishing his return this week to the Queen's Hall. "It's among the best halls for song recitals in Europe," he claims. "It feels friendly, in much the same way as the Wigmore Hall." He also feels at home with its piano, which he can genuinely call his own. "It's a bit embarrassing," he admits. "I was one of four appointed to select the best instrument. When the day came to try them out, I was the only one who turned up." As most singers would say, if you want an accompanist you can rely on, get Martineau. But I suspect there's a waiting list.
• Malcolm Martineau accompanies Simon Keenlyside at the Queen's Hall on Monday 28 August, and Anne Schwanewilms on Thursday 31 August, both at 11am, as part of the Edinburgh International Festival.