Spring a bit late arriving? Never mind: because this lunchtime we’re all about sunshine and the refreshing sound of flute and strings. André Jolivet imagines the music of the ancient world; Villa-Lobos dances into the jet-age. And two very different French geniuses do it their own way: in Roussel’s graceful Trio and Ravel’s rapturous Introduction and Allegro. Chamber music simply doesn’t get any more gorgeous.