To the best of anyone's knowledge, Dustin Hoffman was not at the Kennedy Center Concert Hall yesterday afternoon. Had he been there, no doubt he would have chortled the loudest at the Vienna Choir Boys' charming portrayal of Johann Strauss' frothy operetta, "Wiener Leben," with its standard plot device of chicanery to help the course of young love. He would have seen a bit of his own "Tootsie" character in the young male actors--who played all the roles from the young Hussar Lieutenant Niki to the chambermaids--perhaps putting into perspective his own portrait of an artist as a young woman.

Yet beside the obvious humor of this program centerpiece, Hoffman, like the real audience, would have witnessed a cadre of poised young men, with glorious voices and impeccable timing, capable of pulling off what on the surface might seem to be an absurd undertaking. The "females" even curtsied, rather than bowed, after their ariettas.

The Vienna Choir Boys framed this operetta with a collection of sacred, secular and folk songs ranging from Palestrina to Schubert (himself a Vienna Choirboy alumnus) to Ibert. They were especially effective in conveying the subtle dynamic shadings and lively syncopation of Britten's Missa Brevis and missed none of the gypsy flavor in Koda'ly's "Turo Eszik a Cigany." With an encore that included "America the Beautiful," the singers truly endeared themselves to everyone in the hall.