On July 1, 1966, the station's call sign was changed to WMMR. The call sign reflected the name of the station's owner, "Metromedia" (and "Radio"). (From 1948 to 1993 WMMR was used, unofficially, as a slogan by a local student-run carrier current radio station at the University of Minnesota.) The MOR format was still being used, but with different programming from the AM side, although the AM disc jockeys' announcements were used for both stations. Studios of WIP and WMMR were on 19th Street near Rittenhouse Square.