Hesperus, the early music ensemble directed by Scott Reiss, and Vocal Offering, a vocal quintet led by Evanne Browne, joined forces on Saturday for a program of German Baroque Christmas music at Georgetown University's Gaston Hall.

The music was as fresh and as delightful as the performances, highlighted by some marvelous conversational and competitive give-and-take between the two violins in a stylish Sonata II by Heinrich von Biber, and Christoph Geist's terrific setting of "Wie scho n leuchtet der Morgenstern" (How Brightly Shines the Morning Star) for two viols, recorder, harpsichord and unison voices. There was nothing special about the form of Geist's piece, a choral prelude like untold hundreds of others of the period, but in this performance the instruments danced through their imitative lines while the three women of Vocal Offering sang in the most lovely straight unison imaginable.

A "Canzone a 5 voce" by Samuel Scheidt found the bassoon taking off in unexpected independence from the harpsichord and imitating the recorder with great good humor.

There were also pieces by Schutz, Schenk, Buxtehude, Schein and Praetorius, some of which reflected whispers of Italian influences, but most of which were solidly and comfortably settled into the predictabilities of a well-defined and -developed idiom.