His articles have been published in the United States, Canada, and England and archived in several historical societies, universities, and the Institute of Jazz Studies. Through the years Tumpak has developed personal associations with many of the bandleaders, musicians, and vocalists who participated in the Era. They are the subjects of his articles and provide valuable insights into the culture of the time. Tumpak also lectures on the Big Band Era at public presentations and on radio. He is a member of the Jazz Journalists Association, Los Angeles Jazz Institute, Los Angeles Jazz Society, and serves on the board of directors of the Big Band Academy of America.