If there's a friendlier jazz fes­tival than the event that unfold­ed over the weekend at the South Shore Cultural Center, it has yet to make itself known.

With picnickers gathering along the lakeshore and top flight musicians playing a small stage nearby, the 25th annual JazzFest Heritage Mask Week­end proved that outdoor cultur­al events occasionally can at­tain a surprising degree of intimacy.

Moreover, on Saturday after­noon the weather cooperated fully, giving listeners near 71st Street and the lakefront about as idyllic an outdoor jazz experi­ence as one might hope to hear.

The main attraction was sing­er Andy Bey, a major artist by any measure who happens to be the brother of JazzFest founder-organizer Geraldine de Haas. After offering a touching trib­ute to his big sister; Bey sang the charismatic kind of set that con-certgoers typically pay top dol­lar to hear (bat that JazzFest lis­teners savored for free).

It would not be an exaggera­tion to describe Bey as the pre­eminent male jazz balladeer working today. Clearly inspired by Nat "King" Cole and to a lesser degree, Johnny Hartman, Bey produced a sound that hov­ered somewhere between Cole's crushed-velvet tenor and Hartman's incomparably plush bass-baritone.

Yet there was a great deal to distinguish Bey's work from that of the vocalists who preced­ed him.

Unafraid to indulge in an am­ple vibrato, unconventional phrasings and highly stylized interpretations, Bey acquitted himself as a maverick song in­terpreter, if ever there were one.

But the honeyed tone of his voice and the intense emotional climaxes of his interpretations made his work easily access! Me. At once sophisticated yet unpretentious, highly polished but viscerally expressive, Bey's singing tends to disarm audiences.

Certainly he earned the ovations he received for a radically reimagined "Ifs Only a Paper Moon" and a thorough updating of the Depression-era classic "Brother, Can You Spare a Dime?" That he led his quartet from the piano, playing unorthodox accompaniments. Added to the impact of his work.

Earlier in the afternoon, two notable Chicagoans turned in comparably effective perform­ances.

Guitarist George Freeman may not be as famous as his brother Von Freeman, an iconic Chicago tenor saxophonist, but he played some of the more fero­cious solos this listener has heard from him.

And singer Tammy McCann sounded as big as all outdoors, with a bold style to match.

It's not difficult to detect shades of Dinah Washington in the emotional fervor and tone focus of her singing, but she builds well beyond this ujodc-i as well The somewhat grain-quality other voice and the bte and-bluesy manner of her deliv ery make her a striking figun among today's jazz singers

Here's hoping mat the listen, ing public soon discovers **--power of her art