BLUES POWER: Columbia Records will inaugurate its...

BLUES POWER: Columbia Records will inaugurate its new “Roots ‘N Blues” series with the release of “Robert Johnson: The Complete Recordings,” a long-awaited two-CD (three album) boxed set featuring 41 existing takes of Johnson’s 29 known songs (plus extensive liner notes and appreciations by Keith Richards and Eric Clapton). Due out at the end of the month, the series will also include “Good Time Tonight” by Big Bill Broonzy, “Steppin’ On the Blues” by Lonnie Johnson and “The Big Three Trio,” featuring early pre-Chess work by Willie Dixon. . . . MCA Records is due to release “Bo Diddley: The Chess Box” this week, an ambitious 45-song set that includes Diddley’s hits as well as such obscurities as “You Know I Love You,” a 1960 doo-wop session with the Flamingos with Bo singing doo-wop lead. The set also offers a 24-page souvenir booklet full of rare photos. On deck from MCA: an Elton John boxed-set with a host of rare tracks, which is due in October. . . . Meanwhile, PolyGram is releasing a boxed set of its own, “The Layla Sessions: 20th Anniversary Edition,” which will be out next month. The CD compilation features remixed versions of many original “Layla” tunes, alternate versions of such songs as “To Tell the Truth,” “Mean Old World” and “Have You Ever Loved a Woman” and--best of all--never-before released jams featuring Clapton with Duane and Gregg Allman and Dicky Betts.