I’m not a betting man, but when judgement day approaches and the relevant subcommittee of angels meets to decide on the music most appropriate to welcome the blessed into heaven, I’m going to put my fiver on the Andante from Mozart’s Piano Concerto no. 21 in C major – the piece of music that embodies sublime bliss more than any other I know. On the evidence of last night at Saanen Church, the chances are that they’ll also give Radu Lupu a free pass upstairs to play it for them.

I don’t have a single favourite recording of no. 21 – the work is far too pervasive for that. Rather I have a sort of compendium of memories of ways in which each element is played – the turning of a phrase, a lightness of touch, the holding of a suspended accidental note for just the right length of time before its resolution, a roll of notes executed with perfect legato. And Lupu somehow managed to embody every one of those memories, time and time again exuding the feel that this was exactly the right way of playing those particular notes.

Lupu, to be blunt, is getting old. He looked frail, I’m told that he is troubled by arthritis, and there were fluffs, including a bad one in the third movement, which was swiftly recovered and didn’t matter to me one iota. That frailty makes his style the more notable in that he plays with a total absence of wasted energy. There are no grand gestures, no movement except for the essential: his hands are held in a technically perfect position above the keys and moved to the required place while his fingers do the work, nothing more, nothing less.

Jukka-Pekka Saraste and the Zurich Chamber Orchestra were able accompanists, achieving an excellent blend of sound. In innumerable places in this concerto, a melody or fill is doubled between a pair of different instruments: what was great to hear was that each pairing was perfectly synchronised and balanced so that a new, individual sound was created.

The Mozart was a hard act to follow, and Saraste followed it in the only way possible, by launching into the first movement of Beethoven’s Symphony no. 2 at full power – rarely have I heard the phrase “con brio” mean it quite as much. The “Chamber” in the orchestra’s name tells a story, meaning much more than an orchestra of small size: you could see that these are players who watch and listen to each other, the conductor there to make adjustments rather than needed to keep things together. Their playing displayed wonderful levels of poise  and togetherness, the individual instrumental timbre as strong as their timing was excellent. Beethoven’s second is never going to be anyone’s favourite of the nine: it delivers charm and fun rather than the high drama of later works. It’s astonishing to consider that Beethoven was contemplating suicide when it was written, having learned about his impending deafness.

Stravinsky’s Concerto in D for Strings, the so-called “Basel Concerto”, fared less well. It was included in the programme to provide accompaniment for an artist-in-residence working live to the music, when the same programme was performed a few days earlier in Zurich. Here, the orchestral sound was up to the standards of the rest of the evening, but I didn’t get the same confidence of every note being in exactly the right place; the intensity of Stravinsky’s shifts between spikiness and near-schmaltz failed to persuade. Tight playing at the beginning and end of the third movement didn’t prevent the music from meandering somewhat.

But in the event, that was just the curtain raiser for what turned out to be an evening to remember, a near out-of-body experience with Lupu's Mozart.

David’s stay at the festival was sponsored by Sommets Musicaux de Gstaad.