At 80, B.B. King remains the master bluesman

B.B. King arrived fashionably late to his own birthday party, but when you're a living legend marking your 80th year, no one really minds. Following a 20-minute warm-up led by his music director of 27 years, trumpeter James ''Boogaloo" Bolden, the king of the blues appeared on the Symphony Hall stage in a tuxedo and launched into a gracious two-hour set that spanned a half-century of music: from the '50s gem ''Why I Sing the Blues" and 1969's calling card ''The Thrill Is Gone," to ''When Love Comes to Town" (originally recorded as a duet with Bono for U2's ''Rattle and Hum") and ''I Need You So" from 2003's ''Reflections."

Because of bad knees and chronic back pain, King remained seated throughout, his beloved guitar Lucille slung to his side during the evening's many stretches of storytelling and good-natured joking. He's a born ham and an old-school showman, but also the humblest of icons. King spent several minutes talking to a female fan who rushed the stage to explain her family's connection to his, noting that ''I always stop the show for a beautiful lady." He chatted about his cataracts, marveled at the gender divide, and tossed fistfuls of guitar picks and gold necklaces into the crowd.

And although King fretted that the papers would report that ''old B.B. was pretty good but he talked all night," the truth is old B.B. was astonishingly good. Yes, he talked all night, but the leisurely pace didn't diminish the impact of King's gifts. He sang beautifully, a still-vibrant grasp of nuance guiding him seamlessly between dirty growls and a rich, commanding vibrato. His judicious bursts of bent notes and signature trills -- which still, miraculously, sound silken and fuzzed-out all at once -- remain the blueprint for contemporary blues guitar.

King's seven-piece band, which included his nephew Walter King on baritone saxophone, was supremely classy and well-oiled. Each solo turn, and there were many, was more burnished than the next, and the ensemble's feel for understatement matched the frontman's. Second guitarist Charlie Dennis bundled his runs in tight, muted bouquets during ''Bluesman (Understand)," and longtime drummer Calep Emphrey was a marvel of laid-back precision. Dennis and bassist Reggie Richards joined King on folding chairs to form a guitar-heavy frontline for languorous ''All Over Again," sassy ''Ain't That Just Like a Woman," a couple verses of ''You Are My Sunshine" (as penance, King said, for ''picking on the ladies" in the previous song), and ''Rock Me Baby," where a sleek organ solo doubled as a much-needed beverage break for King.

Who knows what was in those two large cups he guzzled midway through the set. King attributes his enduring vitality to his medical team: ''Dr. Viagra, Nurse Levitra, and Dr. Cialis." To whoever is responsible for this octogenarian's continued well-being, music fans everywhere owe an enormous debt of gratitude.

Joan Anderman can be reached at anderman@globe.com