Jazz was big in Los Angeles thanks to the West Coast Sound (of which Shelly Manne was a part). It also had a couple of top-notch FM jazz stations, KNOB and KBCA. KNOB sold and went to beautiful music in '66, but KBCA had a couple of exceptionally strong years in 1969, when it ranked #8 overall in the ratings and 1970, when it tied for 8th. But in 1971, when the music changed to jazz-rock fusion, KBCA fell to 23rd and never saw the top 20 again. That was about the same time that Shelly's Manne-Hole moved and then closed. There were a handful of small clubs (the Dresden Room in Hollywood, some small clubs in coastal Orange County), but for the most part, that kind of jazz was over and didn't really come back until it became a nostalgia thing in the mid-late 80s/early 90s.