Claudio Monteverdi's Christmas Vespers, which were brilliantly performed last night at the Kennedy Center, bring together three contrasting musical worlds: the elaborate glory of early Baroque Venetian choral music, the gently expressive simplicity of traditional Latin plainchant and the intense, intimately emotional vocal chamber music of the Renaissance madrigal, of which Monteverdi was a supreme master.

To encompass all this variety, the Oratorio Society and conductor Robert Shafer brought in a multitude of helpers, including seven vocal soloists, an orchestra drawn from the National Symphony and two small men's choirs (from Catholic University and the Columbia Pro Cantare) for the plainchant antiphons. The chant choirs were stationed in the top tier, at the extreme front and back of the Concert Hall, and their dialogue across the vast space of the auditorium suggested some of the spatial effect Monteverdi had to work with in St. Mark's Cathedral in Venice.

The soloists were all in good voice, with particularly outstanding work by soprano Jane Bryden and tenor Stanley Cornett. The Oratorio Society chorus was beautifully balanced and superbly controlled, powerful but delicate, transparent in tone and splendidly precise in diction. Shafer conducted with sensitivity to all nuances of Monteverdi style.

For those who love "Vom Himmel Hoch," one of the most beautiful of Christmas songs, the first half of the program was paradise. It was presented first by organist William Neil in Bach's intricate set of Canonic Variations, then by the orchestra and chorus in Stravinsky's Choral Variations inspired by and based on the Bach opus. The superb melody was well served by both composers and all the performers.