Simpson (author, musician, radio host) offers an inside look at the machinery behind radio station formatting and programming during its major evolution in the 1970s. He addresses targeting consumers, the Top 40 phenomenon, the varieties of formats (soft rock, progressive, soul, for example), and the period's continuing legacy. The book includes extensive notes and a lengthy bibliography. Annotation ©2011 Book News, Inc., Portland, OR (booknews.com)