King CrimsonKing Crimson played their first show in April 1969. Two months later?before their debut album was even released?they performed for 650,000 as part of the Rolling Stones’ historic July 5 concert in Hyde Park.

This past Saturday, on August 2, Crimson played another historic concert at Nashville’s intimate Belcourt Theatre. The date was the first of a four-city warm-up for the band’s 40th anniversary next year, when a major world tour is planned. The two nights in Nashville will be followed by concerts August 6-9 at Chicago’s Park West, 11-12 in Philadelphia’s Keswick Theater, and 14-17 at New York City’s Nokia Theater.

King Crimson’s followers long ago abandoned one of their fondest wishes: a reunion of the core ’70s line-up that included bassist/vocalist John Wetton and drummer Bill Bruford. To paraphrase Fripp’s blog on the group’s Web site, if that’s ever going to happen it already would have.

What fans heard instead on Saturday was the frontline of the nearly-as-beloved early ’80s version of Crimson?Fripp, guitarist and singer Adrian Belew, and bassist/Chapman Stick player Tony Levin?marching to the sound of different drummers: Pat Mastelotto, who joined in 1994, and new addition Gavin Harrison, drummer for British prog outfit Porcupine Tree. Harrison, who was drafted into the Crimson fold last year, has a reputation as a specialist in odd time signatures, and he and Mastelotto locked with thunderous accuracy and spirit.

Rumors about the inclusion of original drummer Bruford flew before the Belcourt show. Bruford was, after all, Crimson’s longest enduring and, arguably, most creative drummer, helping to make the ’80s King Crimson classics Discipline, Beat, and Three of a Perfect Pair. But only hardcore fans could have been disappointed by the performance, which ricocheted from precise and rippling excursions through “Indiscipline” and “The ConstruKction of Light,” to visceral takes on “Elephant Talk” and the group’s instrumental cornerstone “Red,” a tune that has encapsulated Crimson’s gifts for the pastoral and the lacerating since their recorded debut in 1974.

There were a few missed notes and out-of-synch twists, but they were barely perceptible due to the unflagging intensity of the performance. Fripp was nearly invisible to the audience as he sat behind his rack of effects outside the range of the stage lights. But he played with grace and his usual efficiency, using his Les Paul-like custom-built, chambered Crimson Signature Model (see how they’re made here) to conjure luminous textures and even to apply fresh sounds to “Red” and other numbers. Belew was less chatty than usual. Perhaps he chose to focus more deeply on his playing, since Crimson hadn’t performed their demanding repertoire live since 2006 and he is, after all, at center stage. But like all of his bandmates, Belew delivered musical sparks, spinning out King Crimson’s trademark high velocity unison and harmony guitar riffs and making his Parker six-string moan like a dinosaur and honk like a Manhattan traffic jam.

Music pundits have often cited King Crimson as the fathers of prog- or art-rock. Although Fripp and his crew have been immensely influential in the realms of metal, noise, and even so-called new age music, both Yes and Genesis beat the band to the stage and to the studio. Nonetheless, thanks to the scope and imagination of recent albums like The Power to Believe and The ConstruKction of Light, and still-incendiary live concerts like the one at the Belcourt, it’s King Crimson that’s not only part of history, but still making it.