An ambitious, admirable, and necessary undertaking, Tommy Boy rolled out a dozen-volume series focusing on rap's early years, treating 'Rapper's Delight' as ground zero and cutting off at 1991. If the first four volumes -- released before the following eight -- are an accurate representation, the series will slant heavily toward the late '80s, when the rap industry really gathered steam, and regularly mix politically charged tracks with party jams and classics with novelties (the difference between the distinctions, of course, wasn't always clear). Some listeners will be displeased with the decision to go with edited versions when necessary. Then again, we're not talking about a period of rap history when tracks required rhyme-to-rhyme profanity to be taken seriously (ask Skee-Lo or Paperboy), so it's really not that much a factor. Apart from automatic picks, like the 14-minute version of Sugarhill Gang's 'Rapper's Delight,' Boogie Down Productions' 'South Bronx,' and Doug E. Fresh's 'La Di Da Di,' the first volume of the series includes several cuts that are just as integral: Marley Marl's star-studded 'The Symphony,' Fearless Four's ecstatic 'Rockin' It,' and J.J. Fad's Dr. Dre-produced 'Supersonic.' The liners contain a brief essay from multimedia hip-hop don Nelson George (which appears in each volume), as well as a personal intro and track-by-track commentary from Jeff Chang (who, with the spectacular Can't Stop Won't Stop, wrote the book on hip-hop).