Fourteen-plus hours of music from any band is a stretch. But for the Chicago of 1971, it’s just right. 

After releasing a four-LP set of its eight-show, April 5-10, 1971, stand at the famed venue a half-century ago and expanding it a couple of times since, the band finally unleashed the entire thing – emcee intros, tuning and stage banter included – as At Carnegie Hall Complete. 

So it’s extra fun when guitarist Terry Kath explains the recording that’s happening and quips: “You’ll probably never hear it because of all the mistakes we’re making.

Little did he know. 

Sporting a discography of three double-LPs at the time, Chicago played a lot of repeats of both hits like “Beginnings;” “Does Anyone Really Know What Time it Is?,” always preceded by Robert Lamm’s improvised piano intro; and “Ballet for a Girl in Buchannon,” trombonist James Pankow’s multi-part suite that includes “Make Me Smile” and “Colour My World,” alongside deep cuts. 

But here’s the thing: every show – two sets at night; one for the matinees – unfolds differently and “Someday (August 29, 1968),” “Introduction,” “Listen,” “Loneliness is Just a Word” and “In the Country” are among the show openers employed during the run. More importantly, no two versions of any songs are the same – or even similar. For the Chicago of ’71 was a quintessential jamband, as much a jazz, psychedelic and rock and roll group as a hit machine and gave no indication of the purveyors of pap they would become. 

Fifty years in the past, Chicago was more concerned with in-the-moment feeling than anything resembling rote consistency. This music is ragged and imperfect – though trumpeter/co-producer Lee Loughnane seems to have cleaned up the horns – and goes a long way toward making the case that guitarist Kath and drummer Danny Seraphine are among the most criminally under-appreciated musicians on their respective instruments. As for Peter Cetera, his bass playing is much more than mere bottom end and that guy could “Sing a Mean Tune Kid.”

The lengthy anti-Vietnam War screed “It Better End Soon” is a monster in every outing with separate movements devoted to guitar and flute solos – dig Walt Parazaider riffing on “Dixie” and “Livin’ in the U.S.A” – and peace-and-love preaching from Kath. “A Song for Richard and His Friends” – which never made it to a studio record – finds the band skewering Nixon and his cronies with Zappaesque humor and precision. And “Flight 602” features the rock band with horns playing country-and-western before segueing into Seraphine’s composed drum solo, “Motorboat to Mars,” and landing on the rambunctious “Free” in a trilogy known as “Travel Suite.”

Pankow’s classically minded, multi-part instrumental “Elegy,” Kath’s “An Hour in the Shower” and the band’s searing rendition of the Spencer Davis Group’s “I’m a Man” appear once each. 

There are other live albums from Kath-era Chicago. But none of them capture the band as raw and hungry – and improvisational – as At Carnegie Hall

And now, the documentation is Complete.