Shaw, a former record producer (""Sh-Boom"" and others) promises a ""comprehensive"" history of R & B, ""an indigenous black art form and style"" that thrived between 1945 and 1960, dominating early rock 'n' roll. And comprehensive it sure is, with references to hundreds of names and titles that were part of the R & B sound--a blend of blues shouting, mindless lyrics, boogie-woogie shuffling rhythm, and electric guitar with wailing saxophones (""body music rather than head or heart music""). Shaw clearly loves this stuff, and he tackles the subject with eclectic enthusiasm, bouncing from musicology to sociology to economics to mini-biography as he gives each bluesman and record producer personal treatment; 25 taped interviews are included, His fervent partisanship, however, winds up being mostly a handicap. Thematic threads (like the sociocultural phenomenon of low-down black music receiving white acceptance) are lost in the disorganzed clutter and the sludge of indiscriminate detail--especially Shaw's obsessive documentation of the development of small record companies. And Shaw's determination to glorify R & B as a distinct mode leads him to stick the R & B label on some doubtful discs; to sneer defensively at ""jazz-critic snobbery""; and to neglect (except for a tiny epilogue) the most interesting musical matter: the R & B influence on music in the last two decades. So--for ardent fans of ""Open the Door, Richard,"" ""The Hucklebuck,"" and ""Shake, Rattle, and Roll"": an exuberant insider storehouse. For those with a broader interest in pop-music or cultural cross-pollination: a vastly well-informed but subjective grab-bag to pick through with care and patience.