While young jam bands such as String Cheese Incident and Widespread Panic are packing large amphitheaters, such as upcoming dates at Kansas City’s Starlight Theater, it seems a crime that the Allman Brothers Band couldn’t manage to fill the 3,300 seat Memorial Hall in Kansas City, Kan., on Tuesday night.

The reigning godfathers of the whole jam band phenomenon, the Brothers have been burning up the road for more than 30 years and they still do it better than anyone else.

Gregg Allman

The lineup has evolved. Only three original members vocalist and keyboard player Gregg Allman and drummers Butch Trucks and Jaimoe remain. Lost to early deaths were legendary original guitar player Duane Allman and bassist Berry Oakley. Dickey Betts, second lead guitarist was let go by his band mates a few years ago.

The current lineup includes longtime members Warren Haynes on guitar, percussionist Marc Quinones and in recent years Butch Trucks’ 22 year-old nephew Derek Trucks on guitar. Trucks’ band, the Derek Trucks Band, served as the opening act Tuesday night.

Warren Haynes

During the first of two long sets, the band concentrated on songs. Opening with “Midnight Rider,” the set featured Gregg Allman singing such blues numbers as “Trouble No More,” “Don’t Keep Me Wondering” and “Must Have Done Somebody Wrong.”

The highlights of the first set were the extended, improvisatory “Dreams” and the climactic, dual lead guitar jamming that took place during Haynes’ “Woman Across The River.”

During the second set, playing song after song took a backseat to extended musical interplay and exploration. This is where the Allman Brothers shine brightest. The twin lead guitars have always been this band’s signature sound and no two guitarists in the band have ever worked off of one another more effectively that Trucks and Haynes do.

Oteil Burbridge

It is the drummers, however, who provide the rhythmic foundation that all this tremendous music is built upon. Jaimoe provides the steady back beat, Trucks has the soul of a jazz player, and Quinones provides color and ornament.

The centerpiece of the set was Mountain Jam, an open form improvisation based on a Donovan melody, which the band has been exploring for most of its history. During its more than half-hour length, it encompassed a percussion ensemble and a glorious flamenco-flavored solo by virtuoso bassist Oteil Burbridge, who joined the band in 1997.

Derek Trucks and Warren Haynes

Throughout the evening it was gratifying to see and hear band namesake Gregg Allman in fine voice and in good humor. With several years of sobriety under his belt, Allman seems focused, singing strongly and regarding his fans warmly, taking time at several points in the show to address them directly.

After an upbeat performance of the optimistic “Revival,” happy fans left the otherworld of an Allman Brothers Band show to the traditional, recorded strains of the band’s soothing “Little Martha.”