On December 14, Aeolian Chamber Players celebrates its fiftieth anniversary of music making at Symphony Space. (Tickets and more info here.) A longtime commissioner of new works, ACP found it fitting to celebrate with another commission: Huang Ruo’s Two Shades. It will be heard alongside other 20/21 pieces from their repertoire by Ralph Shapey, William Bolcom, George Crumb, Luciano Berio, and others.