John Harbison’s Sixth Symphony is a piece shaped by loss
John Harbison’s program note for his Sixth Symphony begins with a dedication: “ . . . to James Levine in friendship and gratitude.’’ Harbison’s new symphony - which will be premiered next week by the Boston Symphony Orchestra - is marked by the composer’s long association with Levine, its now-former music director. It is not much of a stretch to say that his absence from the podium - for this premiere and for the foreseeable future - played a crucial role in the shaping of a piece marked, in different ways, by loss and incompleteness.