I just went to the ratings archive at WorldRadioHistory.com. The R&R Summary only goes back to the Spring of 1975 book, but KSD was a solid second until the Fall '76 book, when SLQ edged it out and KSD dropped to third.
I don’t have many memories of KSD for the first half of the 1970s…and I didn’t live in the St. Louis area until 1972, anyway. KSD wasn’t a station that was going to appeal to a 15-year-old. Neither was KMOX, but we all listened on snow days for school cancellations. KSD didn’t have that reputation, and the school districts all told people to listen to KMOX or KXOK for that information.
KRCH became KSLQ in the fall of 1972 and instantly began draining teen listeners from KXOK and, in my area, KIRL.
Spring '75:
KMOX (Talk): 25.2
KSD (A/C): 11.5
KSLQ (Top 40): 6.1
WIL (Country): 5.8
KXOK (Top 40): 5.3
Fall '75:
KMOX (Talk): 24.5
KSD (A/C): 11.0
KSLQ (Top 40): 5.9
KSHE (AOR): 5.6
KADI (AOR) 5.3
(This----Fall '75---was the most recent book when KFMB hired Scott Burton to be PD)
KSHE had been steadily growing, so had KADI though a fire crippled its coverage for a while. It was about 1974 when my listening moved, first from KXOK/KIRL to KADI, then to KSHE.
I could have been avant-garde, and had no older siblings from which to take cues, but I think it was around this time that listening really started to reshuffle.
Spring '76:
KMOX (Talk): 26.4
KSD (A/C): 8.3
KSLQ (Top 40): 8.1
KATZ (Beautiful): 6.1
WIL (Country) 5.9
KATZ was never a beautiful-music station…it was *the* black-oriented station in St. Louis until the turn of the decade when KMJM came along, and when the owner of KATZ bought the FM station in Alton, Illinois.
(KSD didn't have a PD for the Spring '76 book---Tom Straw wasn't hired to replace Scott Burton until May)
Fun fact: Tom Straw filled in occasionally on KSD-TV to do weather if Dianne White or one of the Weather Corporation meteorologists weren’t available for Channel 5.
Combined took over in April of 1979... the deal (swapping KTAR AM and KBBC-FM in Phoenix) was proposed in October of 1978.
The most recent book they'd have had at that point would have been Spring '78, and while there was further erosion, it wasn't bad:
Spring '78:
KMOX (Talk): 25.3
KSHE (AOR): 8.0
KSLQ (Top 40): 7.7
KEZK (Beautiful): 7.3
KSD (A/C): 6.7
That was a good book for a standalone AM A/C in 1978. And clearly, Combined saw an upside. They bought KCFM, which had a 1.9 as a Beautiful Music station) and created a solid combo.
Some context. It was later in 1978 when KSD began transitioning to a news/talk format, one day part at a time. The full-service AC format wasn’t bad, not bad at all, but do you think KSD would have started the shift to news/talk if it didn’t have to? Another complication was that Pulitzer was under pressure to exit its St. Louis broadcast operations. Yet another complication was that KMOX’s Bob Hyland had no hesitation to hire away talent from competing stations and then underutilize them, just so that talent wouldn’t be available for the other stations. Meantime, on the FM band, in November of that year, KCFM, which was losing the BM audience to KEZK (which was on the old KDNA frequency), moved to a kind of light-rock format that it called “The Natural Turn-On”. If KCFM had stuck with it, it could have been a precursor to AAA. It was like a progressive-rock approach without the harder rock of KSHE. Maybe it was intended for West County yuppies, but did yuppies exist then? Anyway, Harry Eidelman sold KCFM to Combined about a year later; I think Combined had gotten absorbed into Gannett by the time the sale had closed; KCFM went back to beautiful music; KSD was constantly shifting, news/talk, to all-news, to some news, and so on. Finally it found success as country KUSA. It took time for the combo to get traction, in other words.
And none of *that* chunky paragraph even gets into Doubleday’s entry into the market in 1978, first with the revived KWK and then adding WWWK(FM).
When I’m back home, I can look some things up and be more precise on dates. I also have a complete set of the St. Louis Journalism Review from its founding in 1973 up to about 2010 that I should refer to, since the SJR covered broadcasting in some depth.