Oscar Schmidt electric autoharp

Autoharp describes a musical instrument in the chorded zither family. It features a series of chord bars attached to dampers, which, when depressed, mute all of the strings other than those that form the desired chord. Although the word autoharp was originally a trademark of the Oscar Schmidt company, the term has colloquially come to be used for any hand-held, chorded zither, regardless of manufacturer.

Debate exists over the origin of the autoharp. A German immigrant in Philadelphia, Charles F. Zimmermann, was awarded US 257808  in 1882 for a design for a musical instrument that included mechanisms for muting certain strings during play. He named his invention the "autoharp". Unlike later autoharps, the shape of the instrument was symmetrical, and the felt-bearing bars moved horizontally against the strings instead of vertically. It is not known if Zimmermann ever commercially produced any instruments of this early design. Karl August Gütter of Markneukirchen, Germany, built a model that he called a Volkszither, which most resembles the autoharp played today. Gütter obtained a British patent for his instrument circa 1883–1884. Zimmermann, after returning from a visit to Germany, began production of the Gütter design in 1885, but with his own design patent number and catchy name. Gütter's instrument design became very popular, and Zimmermann has often been mistaken as the inventor.

A stylized form of the term Autoharp was registered as a trademark in 1926. The word is currently claimed as a trademark by U.S. Music Corporation, whose Oscar Schmidt division manufactures Autoharps. The USPTO registration, however, covers only a "Mark Drawing Code (5) WORDS, LETTERS, AND/OR NUMBERS IN STYLIZED FORM" and has expired. In litigation with George Orthey, it was held that Oscar Schmidt could only claim ownership of the stylized lettering of the word Autoharp, the term itself having moved into general usage.

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