WHAT A YEAR this has been for regime change. First Iraq, and now the Choir of St John’s College, Cambridge. I am not being entirely facetious. In the cloistered world of the Oxbridge colleges and cathedrals a new choirmaster at “John’s” is at least as seismic an event as a change of manager at a Premiership football club — even if the latter is likely to earn anything up to 50 times the salary of the former.

St John’s and King’s are the Arsenal and Man Utd of the church-music world. And the fact that the two most renowned Cambridge college choirs are just 200 yards apart only adds piquancy to their eternal competition. King’s stands for pristine purity in a celestial building with an acoustic to match — and mounts a carol service which is as famous a musical event as the Last Night of the Proms. For me, however, the St John’s choir, though less exalted, has always had the edge — not technically, perhaps, but in terms of emotional warmth, tonal colouring and a palpable sense of humanity.

But hang on. How can one talk about the enduring characteristics of choirs that constantly change their personnel? The boys disappear at about 13, when their voices break; while the men (unlike in cathedral choirs) are undergraduates who will stay for just three or four years.

The answer lies in the single word “tradition”: an indefinable sense of style which seeps from one generation to the next. At St John’s that tradition was indelibly etched by the late George Guest, a great-hearted Welshman who ran the choir for 40 years until his retirement in 1991 and infused every choirboy and undergraduate with his own musical fervour.

For the past 12 years, however, St John’s has been directed by Christopher Robinson, who came to Cambridge after long stints at Worcester Cathedral and St George’s Chapel, Windsor. He, too, has acquired something of a legendary aura, if only because his perpetually mournful and rumpled demeanour seems so comically distanced from the romantic splendour of his music-making. Happily, the latter has been preserved on a peerless series of Naxos recordings documenting the English choral tradition. The latest, a sumptuous anthology of Charles Villiers Stanford’s choral music, is just out.

“Coming to St John’s was the best thing I ever did,” Robinson says. “Doing repertoire that I had perhaps done a thousand times with a young choir who had never sung it before brought the whole thing back to life.”

Now Robinson is in his final few days at St John’s. His successor is David Hill, who is currently director of the Bach Choir in London, where he has had a galvanising effect on a venerable musical institution that had seemed in danger of lapsing into a fatal complacency. More to the point, perhaps, he was also the organist of Winchester Cathedral for 15 years. The big difference between that institution and St John’s? “The amount of preparation time you get in Cambridge,” says Hill without hesitation. “The St John’s choir rehearses together every day for an hour. That doesn’t happen in any cathedral. In fact, some cathedral choirs exist on less than 15 minutes’ full rehearsal each day, which is frankly about the same as in the bad old days of the late 19th century.”

Though Hill has very different musical tastes from Robinson (expect more Spanish Renaissance music and new commissions, and perhaps fewer English cathedral classics), the quintessential St John’s sound — rich, glowing and highly nuanced — should be safe in his hands. After all, he learnt his trade in this chapel as an organ scholar in George Guest’s heyday. “You can still feel the old man’s presence here,” Hill says. “He rumbles in your bones.”

But there’s one tradition that Hill is determined to change — the one which says that King’s will always be the more famous of the two great rivals. A London agent has been hired to develop tours, recordings and other outside work for St John’s. “It’s about time that people stopped describing this choir as the best-kept secret in Cambridge,” Hill says.

The St John’s recording of Stanford’s Anthems and Services is on Naxos (8.555794)