 Since roughly the early 1990s, however, for reasons ranging from changing tastes to a general dislike of Conn's newer 8Ds, orchestras have been moving away from the popular Conn 8D.Geyer model horns (by Carl Geyer, Karl Hill, Keith Berg, Steve Lewis, Jerry Lechniuk, Dan Rauch, and Ricco-Kuhn) are used in other areas (San Francisco, Chicago, Pittsburgh, Boston, Houston).The CF Schmidt double, with its unique piston change valve, is occasionally found in sections playing Geyer/Knopf model equipment.