By that point he'd already polished off an undergraduate degree at Cambridge, postgrad studies at London's Guildhall and orchestral posts in Innsbruck and Zurich. Now a ripe old 27, he's one of the most respected French horn players in the UK, a regular soloist with his own orchestra and guest principal with the likes of the London Symphony Orchestra and the Royal Concertgebouw. He has even (though he only bashfully admits it) featured on German television with superstar tenor Rolando Villazon. If Frank-Gemmill had played the violin or piano he'd be well on his way to becoming a household name by now. As it is, he's on a quiet crusade to earn the French horn "credit where it's due".
None of the above would have been remotely possible without a tremendous amount of focus, of course, and that comes across after even just a few minutes of talking to Frank-Gemmill. We meet at his Edinburgh flat, a cosy bachelor pad (his term) at the top of a tall tenement beside Greyfriars Kirk. There are bits of French horn everywhere: three full instruments, four mutes, seven bells, a baffling 20 mouthpieces and various horn-themed paraphernalia that makes him cringe. ("The worst I've ever been given were socks that said 'feeling horny': can you imagine wearing those?") There's also a serious-looking road bike in the corner, because, naturally, Frank-Gemmill is a triathlete on the side.
Was he always quite so focused? "In terms of fun-ness, I think I peaked at around 11 or 12," he laughs. "My mum and dad are both teachers - dad economics, mum languages - and it was unacceptable for me to p*** around as I got older." If he hadn't been a horn player he would have ended up an academic, he reckons, and certainly his approach to music is far more scholarly than your average orchestral player. In the SCO he often uses a natural horn (instead of the easier modern valved equivalent) for repertoire that he and the conductor agree suits the raspier, more colourful sound. But it's not as simple as using a particular horn: he'll delve into the original score, the composer's edits, the historical discourse around the music.
It's the process that keeps his intellect engaged, and besides, "there's a limit to how much actual horn practice you can do before it becomes detrimental," he says. "After three or four hours the muscles aren't sensitive any more. At that point if you're young and foolish you just carry on practising ..."
Are there parallels with being an athlete? "Definitely. Nobody's yet done a study of how the minute muscles of your face work, though there are millions of such studies for sport. It would be helpful for us to learn exactly how much practice is beneficial before you bust your chops." He suddenly laughs and buries his face in his hands. "Being a horn player is a weird mixture between the aristocrat of the brass section and a complete pleb. Here I am trying to explain some esoteric muscle formula, and I end up using a phrase like 'bust your chops'."
Frank-Gemmill is artist-in-resident at this year's Lammermuir Festival, a spotlight that he typically diverts to the instrument rather than himself. "I like to think that the horn can be taken seriously as a musical instrument," he says, joking about needing to rescue it from "people with strange facial hair who meet in obscure locations and make sure nobody else is invited." He opens the festival playing Strauss's First Horn Concerto with the SCO, then turns to Brahms: the magnificent Horn Trio and, with NYCoS National Girls Choir, the lesser-known Four Songs Op 17 with two horns and harp.
"Brahms was a geek about instruments and early music. He preferred the sound of the natural horns, even though they were already an anachronistic thing for him to use." But Frank-Gemmill doesn't always stick to natural horn in Brahms: how come? "Because sometimes it's distracting. People are so interested in the nuts and bolts of the old horn that it takes away from me trying to do something with the music."
There's a pragmatism to the way he approaches the instrument and the music industry that is refreshing. He describes his own sound as "generic European", and says that he adapts "massively" depending on which orchestra he's playing with. "Other people probably just go and do their thing. But I think that playing so loudly in the Concertgebouw or so quietly in the LSO isn't appropriate for the context. So maybe I play in an SCO way ..." By which he means flexible. "Stylistically informed, but not like a period orchestra. It also means that chamber music comes easier, because the SCO is generally quiet and sensitive in its approach. This orchestra is good for my horn-playing health. I can't tread water."
The SCO's loose contract structure also allows him about a 60-40 time split between orchestral gigs and opportunities like Lammermuir, or indeed that German TV show that he finds so embarrassing to talk about. "OK fine," he finally says. "It's called Stars von Morgen and it's hosted by Villazon, who's actually a lovely bloke. I was the first horn player to go on this thing, and I only did it for the sake of popularising the horn - honest. Even playing natural horn in orchestra is still considered fairly radical. I take every chance I can to show off the instrument and what it can do."
Alec Frank-Gemmill is artist-in-resident at the Lammermuir Festival, September 13-22.