From the Gordon Skene Sound Collection: http://pastdaily.com/2016/10/02/augu...full-cavities/
I used to listen to KPOL from around 1977 up until the time it became KZLA (1980?). During those years they were moving away from the "Beautiful Music" sound and toward more current pop vocals. (I have a 1979 aircheck of KPOL full of softer Top-40 songs).
Back in the 60s, though, KPOL played much older music...most of the songs on the aircheck above seem to be from the mid-30's, if not a bit earlier. The KPOL of the mid-70s typically played instrumentals no older than about 10-15 years old, IIRC.
Also the aircheck had the AM and FM simulcast, which was no longer done in the 70s.