The Mozart Requiem is a redoubtable piece of music, largely because it is not all Mozart's. Left unfinished at his death, the Requiem was completed by one Sussmayr on commission from Mozart's widow. Only the Requiem aeternam and the Kyrie are pure Mozart, while the rest was either reconstructed from hs sketches or fabricated totally anew. As a result, many musicians in recent years have not considered the work worth performing.

But no such thoughts here. Saturday night, conductor F. John Adams exploded this musical myth and several others. In addition to mounting the Mozart-Sussmayr Requiem complete, Adams had Robert Levin compose an Amen fugue to follow the sequence Dies irae. Levin's fugue was based on fragments left by Mozart which Sussmayr, for some obscure reason, preferred to leave untouched. Brief but masterful and prodigious, the fugue sported a long Brahmsian timpanum roll which acted as a tonic pedal bringing the fugue to conclusion. It was another plume for Levin's many chapeaux.

Performing the Requiem was a carefully picked group of musicians. Adams recruited the chorus of sixty from the Glee Club, Radcliffe Choral Society, and the University Choir. The modest orchestra da chiesa contained some of Harvard's most respected undergraduate musicians. Of the four soloists, soprano Carlotta Wilsen conducts the Radcliffe Freshmen Chorus, tenor Henry Gibbons is the music tutor of Lowell House, and bass David Ripley is a freshman. Adams thus refuted the current contention that a major choral-orchestral work cannot be performed at Harvard without importing most of the necessary musicians from the outside.

This was truly a Harvard requiem--and an excellent one. Conductor Adams brought a superbly disciplined ensemble to St. Paul's and managed to overcome the church's infamous reverberation problems by rigorously controlling volume and by taking tempos somewhat slower than those usually heard on recording.

Adams knows how to save his performers' potential for the proper moment, and he is able to achieve the most striking dynamic effects without the least exaggeration or grotesquerie. He elicited a performance that was clear and enunciatorily precise even in the most complex fugal passages. He was also sensitive enough to maintain a continuous musical line and forward motion in spite of his deliberately slow pacing. Former math major or no, Adams is quite a musician. His Lacrymosa, even if most of the section is not Mozart's, was beatific.

The periodically unfortunate intonation of the orchestra, occasional four-squareness, and general loss of intensity and concentration toward the end were somewhat disappointing. None of these faults, however, was outstanding enough to weaken the overall effect of the performance. This was a young Requiem-powerful, muscular, intelligent, lyric. In marble St. Paul's the result was overwhelming. Those who did not hear this particular Requiem are not likely to hear its kind in the near future, even on the best of stereo systems.