Factory Location: Rockford, Illinois
Serial Number Dates: 1901 - 1960 (?)
The Haddorff Piano Company was established by Charles Haddorff. The company was eventually aquired by Krakauer Brothers of New York City. Other piano names associated with Haddorff are Clarendon & Bush, Gerts, Temple, Brooks, Evans, and Zellner.
Information source: Pierce Piano Atlas