Greenleaf expanded and upgraded the Conn plant to increase production and developed new lines of wind instruments to sell. By 1917 the assembly-line work force had increased to 550 employees who were turning out about 2500 instruments a month using a new hydraulic expansion process which Greenleaf introduced to the plant. In 1917 Conn introduced the "Pan American" brand for its second-line instruments. Conn founded the subsidiary Pan American Band Instrument Company in 1919 and later that year moved production of second-line instruments to the old Angledile Scale factory. In 1930 the Pan American company was absorbed by Conn, but the Pan American brand for Conn's second-line instruments remained in use until 1955.