104.5 FM began operation on June 8, 1947, as KIXL. KIXL (pronounced "Kicksil") aired a successful beautiful music format, simulcast on both 104.5 FM and 1040 AM ("104 on both dials"). A pioneer in the "mood music" format, the station showed up in the top five in Dallas market ratings consistently through 1968, but by the beginning of the 1970s KIXL was facing tough competition from KOAX, which had come to dominate as the top-rated easy listening station. In 1973, the year Dallas and Fort Worth were combined into one radio market, KIXL dropped its heritage calls in favor of KEZT, continuing to play easy-listening musical fare. The change did not improve the station's fortunes, as KEZT never appeared in the top 10 of the Dallas/Fort Worth ratings, while KOAX's success continued and 100.3 KTLC provided additional competition in the beautiful music format.