As he sat down behind the piano at the Hungry Brain on May 16, the 81-year-old Chicago pianist Erwin Helfer introduced himself to the 20 or so people in the club. “This is the Erwin Helfer trio — me, the piano and the stool,” he said, displaying his wry sense of humor. Helfer, who plays a free … Continue reading Erwin Helfer at the Hungry Brain