Sir Colin Davis has about him the sense of someone who will always be with us. Last December he stepped down from 11 magisterial years as principal conductor of the London Symphony Orchestra, ready (you'd think) for a quieter life as he approaches the age of 80. Less than a month later he was back as the LSO's president, a title that, he says, "means blissfully nothing in practical terms, but just signals the fact that we still have a relationship and will continue making music. Which makes me happy. I'm being indulged in my old age."

There's an element of teasing disingenuousness when Sir Colin represents himself as old. He has been doing so for half his life, after a stormy youth in some of the toughest top jobs in British music — Sadler's Wells Opera, BBC Symphony, and the Royal Opera, Covent Garden — which left him weary of the machinations that it takes to build a neon-lit career. Stepping back, he acquired a new persona — ruminative, zen-like.

He also learned to knit; it helps him think. And, as he told me once, "that's the chief task of a conductor. Players don't have time, but conductors should be thinking 'What is this piece?' Not in a panic, not 'What on earth can I do with the B-minor Mass when I've done it so often before?' but 'How can I set it up to ensure that, like all the great works of the past, it will survive?' This is what absorbs the mind."

In recent years Sir Colin seems to have focused ever more closely on core, select repertory — Sibelius, Berlioz, Mozart — played with core, select orchestras, not least the New York Philharmonic, with which he has appeared more than 120 times over four decades. This month (March 22-24 and 28-31) he's with the Philharmonic again, celebrating his 80th birthday with pianists Mitsuko Uchida and Radu Lupu in yet more Mozart, as well as with Sibelius's complete Lemminkäinen Suite.

Asked if he isn't of an age to be cutting down on transatlantic travel, he's equivocal. "It's not the flights so much as the exasperating nonsense of U.S. Immigration procedure that gets to me, but I'll bear it as long as I can because there are U.S. orchestras I love to conduct. When I started coming here, back in the '60s, they gave me a confidence that was critical at the time. Now, they're pure enjoyment."

Formerly chief music critic at The Independent in London, Michael White presents programs for the BBC and contributes to the London Telegraph and The New York Times.