In taking full measure of Von Freeman's substantial gifts as a jazz saxophonist, it's best to get the age issue out of the way as soon as possible. Freeman is 81. Approach his latest album, "The Great Divide," with that in mind, and his gifts as a vital, uncategorizable stylist loom even larger.

Yet Freeman's triumphant art far transcends a case of body and spirit defying time. This Chicago tenor legend may indeed perform with the vigor of a man half his age, but it's the imaginative content of what he plays -- and how he plays it -- that sets him apart. In Freeman we hear an uncanny mixture of authentic swing and bop influences transformed through a highly unconventional approach to phrasing, tone and pitch that links him to jazz's avant-garde. His work feels timeless, a conjoining of disparate styles and sugar-and-salt sounds that could only be connected by an original mind.

Freeman may be a national jazz treasure, but outside of his home town he is little known. It's a different story in the Windy City, where a street bears his name and Northwestern University granted him an honorary degree, and where he has led a now-legendary weekly jam session at a club for more than 30 years.

Chicago's affection for Freeman may have a lot to do with his loyalty to the place. Over the years he has played alongside a slew of Second City talents who, having honed their craft, then packed up to make their reputation in New York. Freeman stayed put. His family was there, including his son Chico, an esteemed saxophonist himself. And there was no shortage of greats passing through; as a younger man Freeman jammed with Lester Young, Coleman Hawkins, Charlie Parker and Dizzy Gillespie. His Chicago musical cohorts included Sun Ra, Andrew Hill and Ahmad Jamal.

In truth, though, Freeman has always been such an idiosyncratic player that popular recognition might have eluded him anywhere. He never lets you get too comfortable with his playing; no matter how swinging or sensuous a mood he may set, Freeman will then dive into a tonally ambiguous, improbably phrased passage that's as unexpected as it's delightfully expressive. This isn't, and thankfully will never be, made-for-prime-time tenor.

"The Great Divide," which is to be released July 13, reunites Freeman with an early associate, drummer Jimmy Cobb, the last surviving member of the Miles Davis band that recorded 1959's "Kind of Blue." Cobb brings along two members of the Cobb's Mob quartet, pianist Richard Wyands and bassist John Webber, and their spirited ease fits the saxophonist perfectly. The album brilliantly illustrates Freeman's flair for mid- and up-tempo swing ("Be My Love," "Disorder at the Border," "Hard Hittin' "), blues meditations ("Blue Pres"), luscious ballads ("This Is Always") and even a one-chord, free-tempo improvisation that hints at Coltrane-era openness ("Chant Time").

The album concludes with a seven-minute, unaccompanied saxophone reading of the now little-played standard "Violets for Your Furs," a tour de force of instrumental control and openhearted emotion. In his golden years, Freeman brings together a bullfighter's daring with the maturity of a wise, and soulful, older man.

Von Freeman's latest CD showcases his highly unconventional approach to phrasing, tone and pitch.