Two final-year students in the Royal College of Surgeons have taken a piece by Rachmaninov, that is widely considered to be the most difficult ever written for piano, and have made it even harder, writes Arminta Wallace

Hands up everybody who knows Rachmaninov's Third Piano Concerto? Quite a few. And hands up everybody who has ever heard it performed, in its entirety, by a piano and organ duo? Hmm, thought so. Nobody. Which is why next week's performance of the work at the National Concert Hall will be - to say the least - unusual. Especially since the performers will be not professional musicians, but final-year students at the Royal College of Surgeons in Ireland.

It sounds like some sort of illusion or digital trick, but Diamond Tam, from Canada, and Jerry Martin, from Galway, have been working on this highly idiosyncratic version of the piece for years. Now they are waiting at the other end of a phone line, keen to explain themselves. The first question has to be: why? Why take the piece which is widely considered to be the most difficult ever written for piano, and make it even harder? "Ah," says Diamond Tam. "I was taking piano lessons with John O'Conor, and I told him I wanted a challenge. I said, give me the hardest piece you can think of. He suggested the Rach Three. That's how it started."

Tam and Martin met up in college. Martin suggested an organ transcription: "I said, 'Yeah, right. I'll believe it when I see it'. A couple of years later he said, 'OK, I've finished'. Then it became a matter of finding a place to play it - to match the organ and piano acoustics. Peter Sweeney suggested the NCH, so we tried it and it really worked well." Second question. Why is he called Diamond? "Well, my parents couldn't decide on a name, so they sat down and talked about what character traits they wanted me to have. And Diamond being a lot of things, like, um, I mean, sort of . . . a hard substance and a symbol of clarity and, ah, unity. . ."

Moving hastily back to the music, how does it work, this transcription? Is it that he plays the solo piano part and Martin does everything else? "Exactly." So the organ becomes an entire orchestra? "That's right." How? "Well, you know, Jerry is sitting right here beside me, so would you like to ask him?" Jerry Martin is, it turns out, completely unfazed by what he is about to do. "Going back to the time of Bach, it was traditional that pieces written for combinations of other instruments have found their way on to the organ," he explains calmly. "And in the past 200 years, a number of different performers have taken whole orchestral works and transcribed them. So I thought, why not give it a try?" He sat down with the score and a clutch of recordings. "The strings are often the foundation for the basic harmonic structures. But listening to the Rachmaninov score, there are some beautiful melodies and intricate harmonies hidden in there. Sometimes you just have to take those out - and the organ has an almost limitless array of sounds - so I've done that. But my aim was to preserve as much of the character of the piece as possible."

Both Martin and Tam have been studying music for many years. Martin began at age four with traditional fiddle, then added the piano. When he was 12 he was, he says, bitten by the organ bug. "It never ceases to amaze me what you can do on the organ. It's a fantastic instrument to play," he says. Tam, meanwhile, had acquired a performing diploma in his native Canada by the time he was 10, despite a horrific saga following botched surgery on an arm fracture at the age of five - which he gleefully describes in all-too-vivid detail.

"I had at least a year of physio every day," he says. "But what I remember most was something they called a nerve conduction study - where they stick a long electrode pin into the nerves in your arm, then give you electric shocks to see if they respond. They had to strap me to the bed. I used to scream, 'I wanna go home'." Trauma wouldn't be in it. But the experience now drives him as a medical student. "My biggest interest is in paediatric medicine. I can relate to kids on a different level, and when I settle down, that's what I'm gonna do," he says.

Both Tam and Martin are preparing for final exams in May - a task that would be more than enough to keep most people occupied, without transcribing and performing the Rach Three into the bargain. "Well, the more you have to do, the more efficient you are with your time," says Martin. "And music is a great release. Studying medicine can be really high-stress; music takes you off to another plane."

So are any other final-year students at the Royal College of Surgeons in Ireland involved in artistic projects that we ought to know about? "Well," says Tam, "there's a guy who. . ." There is a muffled exchange at the other end of the line. "Doesn't he do Michael Flatley or something?" On second thoughts, let's leave that for another day.

Diamond Tam and Jerry Martin play Rachmaninov's Third Piano Concerto at the National Concert Hall Thursday March 6th at 8 p.m.