(CNN) -- Lee Abrams, Congress and capitalism played major roles in shaping today's AM and FM dials.
As a consultant in the '70s and '80s, Abrams (with his business partner, Kent Burkhart) devised the "Superstars" album-oriented rock format that many FM stations, once bastions of free-form radio, followed.
The stations became incredibly successful, pushing once-powerful AM music stations to news, talk and sports. (Those AM stations, looking for programming, in turn made stars of syndicated talk-radio hosts.) But they were also slammed by many critics and listeners for marketing a rather homogenized sound.
From there, money and Congress took over. The 1996 Telecommunications Act relaxed limits on radio station ownership and radio companies sometimes bought several stations in the same market. Criticism of corporate radio deepened in the '90s, especially after companies tightened playlists and automated or simulcast functions.
Well before that time, Abrams had moved on. He defends his early work -- "If anything, we saved [FM radio]," he says, noting that free-form stations were too "out there" for many listeners -- but says that terrestrial radio now has "way too much discipline."
CNN.com - How terrestrial radio got here - Jul 20, 2006