Immediately following the success of his Marimba Symphony Orchestra for the Century of Progress International Exposition, Clair Omar Musser created another such ensemble in 1935. Musser took his International Marimba Symphony Orchestra comprised of 100 members playing instruments of his design built by the J. C. Deagan company on a tour of Europe. The IMSO returned to the United States to perform a concert at Carnegie Hall. The King George marimbas were made especially for each individual player complete with a personalized British coat-of-arms. Among other unique features are frames with brass end posts and brass resonators with three temperature height adjustments.