Coming at a time when the thread linking country music to its black-music roots threatens to dissolve like so much surgical stitching in today's polarized society, Rhythm Country and Blues offers small pleasures in pressing its point. On a couple of occasions it even rises above the commonplace in spectacular fashion.

Only a couple of tracks are outright failures. Dueting with Gladys Knight on the Marvin Gaye-Tammi Terrell classic "Ain't Nothing Like the Real Thing," Vince Gill sounds like a wimp, his soft, airy readings blown away by Knight's fierce delivery. Similarly, one assumes the applause heard at the end of Al Green and Lyle Lovett's rendition of Willie Nelson's poignant "Funny How Time Slips Away" is for Green, because nothing about his partner's contribution is worth celebrating. Green proves that he can climb inside a song's heart and rummage around for the most piercing feelings as well as anyone. Seemingly benumbed by Green's artistry, Lovett skims the surface, his idiosyncratic style exposed as artifice when called upon to deliver something deeper than irony.

Elsewhere, better-considered matchmaking produces transcendence. The Staple Singers tackle "The Weight," which they scorched in The Last Waltz. It's tough to stand up to Mavis and Pop Staples, who don't give an inch to Marty Stuart in their fire-and-ice vocals, but Stuart delivers his parts with precisely the right blend of ennui and character, then steps aside to let the Staple Singers roll on. Aaron Neville and Trisha Yearwood team on Patsy Cline's "I Fall to Pieces" and turn it inside out, demonstrating a remarkable camaraderie – these two should do an entire album – and a scintillating gift for discovering new shades of hurt and longing in one of country's signature songs.

Special mention should be made of the inspired Sam Moore-Conway Twitty take on "Rainy Night in Georgia," a great Tony Joe White song made memorable in its original version by the late Brook Benton. Moore's urgency plays off Twitty's languor in drawing a sorrowful portrait of a man at emotion's edge. As the music winds down, the two singers fall into a brotherly dialogue that fades out with Twitty calling out plaintively, "Ohhh, Brook Benton, where are you, son?" Shortly after this session, Twitty himself was dead. On the strength of this class performance alone, he should be remembered with the same warmth he summons in invoking Benton. (RS 680)

DAVID MCGEE