A starry trio gives us one of Beethoven’s most delightful concertos. Mutter and Ma were two-thirds of Karajan’s celebrated lineup back in 1985, and they still blend beautifully. With Daniel Barenboim in charge from the keyboard, this performance has a lovely chamber-music-like feel to it, all three soloists bouncing themes back and forth with palpable joy, and the live occasion simply adds to the magic. Symphony No. 7, Barenboim’s fourth recording of the work, was recorded live in Buenos Aires, the city of his birth, and he conducts it with love and authority, drawing spirited playing from his young orchestra.