Only a fool leaves their mobile phone on when Alfred Brendel is playing. But the church bells of St James, Chipping Camden, answer to a higher authority and struck eight during a particularly sublime moment of the Andante of Mozart's F major Sonata K533. There was a flicker of annoyance on Brendel's face, but he knew that, for once, he was beaten.
St James is a glorious, confident Cotswold church - part Norman, part 15th century. The local wine merchant Charlie Bennett has somewhat improbably made it the centre of an enterprising festival, attracting musicians of a very high calibre to play among the sheep-stippled fields. One reason is the acoustic: Brendel thinks it one of the best he has ever known.
The audience arrive in a mix of jumpers, tweeds and jeans. Brendel responds in white tie and tails. He is 77 and in the last few months of a career that has seen him play in every major concert hall in the world. This was never going to be a dress-down Thursday.
When a great artist proposes to leave the stage you listen all the more intently. Stylists want to hang on to every note of a technique and manner learned from Fischer and Steuermann in the 1930s and 40s. When Brendel stops performing at the end of the year, a precious link with the past will have gone. As he grows older, Brendel gets simpler. His delight in "discovering" the piano sonatas of Mozart in his 70s was a clue. Brendel, the intellectual, is as attuned to complexity as any thinking artist. But the greatest artists see beyond complexity to simplicity - and that is where he has arrived in this last period of his playing.
Listening to late Brendel is to have the greatest music (Haydn F minor variations, Mozart, Beethoven Op 27 No 1, Schubert D960) stripped back to its essence. You wonder why other pianists would want to make it faster, or flashier, or fussier. There is a sort of perfection in this late-style simplicity. Catch it while you can.