Blues credibility doesn’t get any deeper or more real than Robert Lockwood Jr. On Delta Crossroads (Telarc 83509; 61:14), the 85-year-old Delta bluesman lays out a heartfelt homage to the immortal Robert Johnson, his guitar teacher, close friend, role model and possibly step-father. Playing the acoustic 12-string guitar and singing with uncommon authority, Lockwood delivers unaccompanied, bone-chilling renditions of Johnson classics like “32-20 Blues,” “Stop Breakin’ Down Blues,” “Mr. Downchild,” “Love In Vain Blues” and “I Believe I’ll Dust My Broom,” along with authentically earthy readings of Leroy Carr’s “Mean Mistreater Mama” and “In the Evening,” Lightnin’ Hopkins’ “C.C. Rider” and “Key to the Highway,” which Lockwood says was written by Jazz Gillum and not Big Bill Broonzy, who usually gets credit. I guess he would know. This purely acoustic offering is a rich tribute and a must for Delta fanatics.