 To distinguish their pianos, Kohn & Karbach put sometime after 1920 the Schweighofer Original inscription on their instruments and added the Karbach name on the soundboards.1938 Karbach and Kohn, who were Jewish, were expropriated under the Nazi regime and the company was subsequently led by Friedrich Ehrbar jr., another Viennese piano maker, until 1940 when it was closed.The other company, owned by the Schweighofer family descendant, also disappeared during the second world war .