 At the heart of the Group were its performers.Aside from Krosnik, Sollberger and Wuorinen, others who were central to its early and continued success included Sophie Sollberger, flute; Josef Marx, oboe; Arthur Bloom and Jack Kreiselman, clarinets; Donald MacCourt, bassoon; Barry Benjamin, horn; Ronald Anderson, trumpet; the brothers Robert and James Biddlecome, trombones; Raymond DesRoches and Richard Fitz, percussionists; Robert Miller, pianist; Aleck Karis, pianos; Susan Jolles, harp; Jeanne Benjamin, Benjamin Hudson and Linda Quan, violins; Jacob Glick and Lois Martin, violas; Fred Sherry and Peter Rosenfeld, cellos; Bertram Turetzky, Donald Palma and Kenneth Fricker, contrabasses; and Valarie Lamoreaux, soprano.Conducting duties were shared by Sollberger and Wuorinen and later with Gunther Schuller.