Jazz has inspired the broadest range of academic musical attention, from musicological analysis to jes'-folks ""oral history,"" and this scholarly, well-intentioned study welcomes any and all perspectives without achieving any particular voice, thesis, or energy of its own. Unlike some Jazzuits, Tirro happily includes ragtime, swing, and the blues as part of Jazz, the Great Undefinable, and each receives its own compartmentalized chapter as the author (Duke Univ.) traces the evolution of African music into Black American music into the sounds of New Orleans, Chicago, Kansas City, and beyond. Along the way, specific forms and specific compositions/ arrangements/recordings receive technical, classroom-like scrutiny--which may prove too intense for ""an introduction to the principal movements, schools, performers. . . ."" (The in-depth analysis does, however, produce such fringe benefits as the complete lyric for ""What Did I Do to Be So Black and Blue?"") And Tirro's attempts at sociological touchstoning add a few overstated thuds to a style which, in any case, never rises above basic blah (""The Blues is a personal statement in musical terms which is nevertheless valid for all members of a society""). Still, the eclectic evenhandedness here is a welcome change from the ivory soundchamber of many jazz purists, and profuse references to available recordings (especially the Smithsonian Collection of Classic Jazz) should make it easy for the zealous reader to listen as Tirro lectures.