Kirsten Johnson is the best ever expositor of the elusive, allusive, lyrical music of Amy Beach. Beach needs exposition. Too often her would-be expositors have confused exposition with attempted explanation. The result? The music has been neutered and demystified. Beach needs too, to an extent that few other great composers do, a passionate and sympathetic conductor of her extraordinary musical electricity. Until now, she hasn't had one, and so has been unfairly dismissed as a clever, quirky composer, tripping rather irrelevantly through minor New England concert halls and salons. Johnson has given Beach the voice she always had, but which no one (including, perhaps, Beach herself) had ever heard. It's wonderful.