Jim Maddux, 1580 KDAY Los Angeles | March 15, 1976

Despite it’s years as a mainly R&B and Soul station, 1580 KDAY would earn it’s place in the sun as what could be termed the very first “Rock 40” format – some 8 years before WLS Chicago earned the format title. The format was relatively short lived, two or three years, from what I remember people telling me, but in some ways, KDAY became legendary, if not for the Rock 40 format, for it’s ‘first in the nation’ Rap format which followed on from roughly 1977 through the 1990s.

This recording is from the end of the Rock 40 format.

Not knowing much more about the background of this station, I’ll once again invite our West Coast ‘expert’ to share his thoughts, and perhaps you have some personal memories of this AM Rocker that you’d like to discuss with ol’ CalRadioPd – I’m sure he’ll be along shortly!

Most searches will bring up the current day 93.5 KDAY, a Hip Hop station in Los Angeles.


  1. Joe Crain

    Rock-40 Format? Where’s the rock on the aircheck? Earth, Wind & Fire, Smokey Robinson, Supremes, etc. are heard on the aircheck… hardly rock, more like what KDAY was known for over the years—straight ahead R&B. Just sayin’…

  2. Rock-40 is news to me. Jim Maddox hired me in June of ’74. In March of ’91, I personally signed it off. Joe Crain has it right. 1580 KDAY, at that time and, actually, until the end, was an R&B station, though we did innovate by playing rap when no one else did, thanks to Steve Woods, who was PD in ’79.

  3. calradiopd

    Somebody’s Wayback Machine needs calibrating.

    The “Rock 40” format was under Bob Wilson and lasted from 1971 to 1973. In January of 1974, Jim Maddox (spelled with an “o”, not a “u”) took over and went R&B, immediately blowing the legendary but underpowered KGFJ into the weeds.

    By the time of this aircheck, they’d been doing it for more than 2 years.

    How good was it? KDAY’s last “Rock 40” (they didn’t call it that) book was a 1.4 share and 23rd place. A year later, they were #3 with a 4.6. They were within 8/10ths of a point of KHJ in fall ’75.

  4. Lew Irwin

    Steve, would you happen to have an aircheck of Wolfman Jack and me on KDAY in the early 70s? (I did the newscasts.)

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