Kronos Says Goodbye to Two Members After a Hello to Moondog and Sun Ra Many are celebrating the tenures of two members of Kronos Quartet – violinist John Sherba and violist Hank Dutt – who are, after more than forty-five years, retiring from the group at the end of June.   As a valediction, I have been listening to and enjoying recordings from throughout their catalog. I am impressed by how enduring the quartet’s creative vitality and imagination has persisted, even on their most recent outings.   Joined by the Ghost Train Orchestra and a number of guest vocalists, last