The DU Lounge

which were playing Top 40. Top 40 radio was not a musical format; it played whatever was selling, whether it was rock, pop, Motown, country, big band, show tunes, jazz etc. It was largely a melting pot; most people listened to it because there was usually something on that they liked.

FM started niche programming. Disco was the niche of the moment. People who loved disco went to the FM stations that were playing it nonstop. AM Top 40 stations tried to counter by adding more disco. That pissed off the people who hated disco, and didn’t attract the disco lovers, because they could listen in stereo on FM. Top 40 stations lost listeners from both ends of the spectrum.

By the early 80s, many Top 40 stations were changing format, ironically, at the same time disco was flaming out because people were getting sick of how repetitive it was.