A jangling of sleighbells, a little flurry of birdsong from the flutes 鈥 and is that a melody by Mozart? Not quite. Mahler鈥檚 Fourth Symphony might be his most classical in proportion, his most playful in style 鈥 utwardly, at any rate. But from deceptively innocent beginning to the 鈥渃hild鈥檚 vision of heaven鈥 with which it ends, the Fourth has depths as poignant and profound as anything Mahler ever wrote. 成人论坛 SSO Conductor Emeritus Donald Runnicles is just the person to draw out its inner drama, and he鈥檚 joined by soprano Carolyn Sampson 鈥 who begins with two gloriously fresh vocal showpieces by the composer Mahler loved above all others: Mozart himself.