To the Festival Hall this morning with Bob to attend an Open Rehearsal of the Simon Bolivar Youth Orchestra from Venezuela. By the time we got round to asking about tickets for their two London concerts, they had long been sold out. This open rehearsal is our only chance to hear them, and at 10am the Festival Hall is packed.

Their conductor, Gustavo Dudamel, clearly understands that many of us are there because we couldn’t get into the evening concerts. Although it’s ‘a rehearsal’, he generously treats us to a more or less continuous performance of Tchaikovsky’s 4th Symphony and Bartok’s Concerto for Orchestra despite the fact that the orchestra has to give a full concert this evening. I had seen their now-famous Prom on television last summer, so I knew they were marvellous, but it was still extraordinarily touching to hear them live. Quite apart from their blazing sound, what’s so striking is the unselfconscious gusto and commitment they bring to classical music.

Before the rehearsal begins, Dudamel has to climb up to the percussion section at the back of the orchestra to discuss something with them. On the way through the orchestra he seems to reach out and touch a number of the players on the shoulder with a natural friendliness, and they reach out and touch him back. This is something I haven’t seen before on the symphony stage.

At the end of the first movement of Tchaikovsky, someone shouts ‘Bravo!’ and the audience bursts into prolonged applause. I am so overcome that I can’t say anything to Bob, and he can’t say anything to me either. I look in my bag for a tissue and wipe my eyes. I hand the tissue to Bob who wipes his eyes as well. And it is still only 10.30 in the morning.