The station's format was changed to adult contemporary on October 22, 1975 at 6:00 a.m., during Charlie Tuna's morning show when KKDJ began simulcasting with KIIS 1150 AM with an "on-air wedding" which "married" KKDJ to KIIS-AM. At that time, KKDJ's call letters were changed to KIIS-FM. The spelling of "K-I-I-S" instead of KISS, was because it resembled the AM frequency: "1150"="IIS". The new merged station was referred to as, "AM and FM, K-double I-S."
