Jazz in the studio vs. jazz recorded live.

It's been a year of archaeological wonders for jazz fans, one in which long-lost recordings of legendary concerts have been excavated, restored, and released on commercial labels. The highlights:

*The Dizzy Gillespie-Charlie Parker quintet at New York City's Town Hall in June 1945 (unmarked acetates unearthed in a Connecticut antique store);

* Thelonious Monk's quartet, with John Coltrane, at Carnegie Hall in November 1957 (tapes discovered during a routine inventory at the Library of Congress);

* John Coltrane's quartet at the Half Note in the spring of 1965 (tapes found in his widow's closet).

While the Half Note sessions have been floating around for years on bootleg labels (which were incomplete and in poor sound, made from copies of copies of copies), the Town Hall and Carnegie Hall concerts came as complete surprises. All these decades, nobody has known, or everyone had forgotten, that they had been recorded. More stunning, they're not mere collectors' items; they turn out to be some of the most thrilling performances, by some of the greatest musicians, that have ever been preserved on disc.

Which prompts a thought: Maybe jazz musicians should record fewer albums in studios and more before live audiences, in nightclubs or concert halls, where the music naturally belongs.

Parker and Gillespie's 1945 studio recordings stand as path-breakers. They mark the beginnings of bebop, a new style of jazz that extended the art of improvisation, with musicians building their solos on the chords of popular songs in syncopated rhythms and at blazing speed. But they sound almost quaint compared with the Town Hall concert, which took place only a few weeks later. Listen to the two versions of "Salt Peanuts." The studio take, recorded May 11, has the casual sway of the swing era; Parker's alto-sax solo is brilliant but compact. The Town Hall performance, on June 22, is a blast into the jet age; there's a ferocity that's hair-raising even now.

In part, this disparity between live and studio performance is a simple matter of time. On the 78-rpm recordings of the day, musicians had to keep a song to a few minutes and a solo to shorter still—eight bars, 16 at most. At a live date, there were no restrictions, so the songs could go on for at least twice as long, and so could the solos. The difference is not just the extra length but also the freedom to stretch and experiment: If the soloist gets lost in his first chorus, it doesn't matter since he can push it further and get it right in the second chorus or the third. And, of course, Parker and Gillespie never got lost, and they never played a chorus the same way twice. So we wind up with a new set of masterpieces that are more adventurous than anything we'd thought these two were playing so early on in their collaboration.

The Monk-Coltrane concert at Carnegie Hall is remarkable in a different way. The quartet had been formed in July 1957 to play at the Five Spot, a music bar on Manhattan's Lower East Side. The engagement marked Monk's return to the live jazz scene after five years and Coltrane's return to vitality after kicking heroin. The quartet was so popular that the gig was extended for six months. The band recorded just one studio session, near the start of their stay at the Five Spot. The Carnegie Hall date took place in late November, near the end. They'd been playing together almost every night for four months, and they'd become a "working band." They knew each other's moves; each of them could take wild excursions without fearing that the others would lose step.

The studio sessions, classic as they are, sound studied and stiff compared with the Carnegie concert. At Carnegie Coltrane blazes in his solo on tenor sax, Monk shuffles tempo and lays down unexpected accents on piano, while the rhythm section shifts and swings. In the first couple minutes of "Monk's Mood," the concert's opener, Monk and Coltrane float through the chords as if in meditation, opening up spaces that neither would have dreamed of indulging at an eyes-on-the-clock studio date. Or check out the opening of "Epistrophy," where drummer Shadow Wilson taps out a straightforward beat on the studio session —but clangs a Latin rhythm on his cymbals in the early set at Carnegie, then a completely different, staggered, hard-boiled rhythm in the late set.