It isn't often that a blues musician appears on stage wearing a tuxedo, but then, B. B. King is no ordinary bluesman.

King is still the master of Memphis blues, and didn't let a little thing like a black tie and a few frills prevent him from breaking a sweat or displaying his command of the guitar time and again last night at Constitution Hall when he appeared with Bobby "Blue" Bland.

It's tempting to take King and Bland for granted. They've been singing the blues for so long, it's easy to overlook the lasting effect they've had on popular music. Their recent records, often slick and lifeless, haven't helped matters any.

But in concert, the two still cook. No one teases an audience or phrases a ballad quite like Bland. He leaned heavily on classics like "Stormy Monday," his smoldering vocals sharply offset by a punchy horn section.

King also played hard, aggressive blues from the outset. "Outside Help" moved swiftly from pain to anger to sweet revenge, and "Let the Good Times Roll" released the tension just as quickly. Bland's impromptu duets with King near the end of the show were full of the surprises that King's solo concerts generally lack.