Ann Arbor German-American family, owners of the Allmendinger Organ Company which later became the Ann Arbor Organ Company. Correspondence, scrapbooks, family genealogy, photographs concerning family affairs, materials on Helene Allmendinger's radio show, examples of spirit messages received by Helene Allmendinger from deceased family members; information pertaining to the Ann Arbor Organ Company, and family members still living in Germany.
The collection is divided into the following series: Family records and correspondence; Helene Allmendinger papers; Ina Allmendinger papers; Ann Arbor Organ Company; Harriet Birch papers, Other family members; Miscellaneous, and Photographs.