HARVARD's musicians and concert-goers are raving about Yo-Yo Ma, guest cellist with the Bach Society Saturday night. He is, no doubt, the most phenomenal soloist who has played at Harvard this year, and Janos Starker was certainly no small event. Yo-Yo's performance of the Haydn D Major Cello Concerto surpassed anyone's imagination of the piece. The best way to summarize his performance would be to say that it was Yo-Yo, and that Yo-Yo can be compared to no one in the world.

Wisely, conductor Robert H. Baker chose to end the concert with the Concerto instead of Haydn's 99th Symphony in E flat. The audience held its breath through Yo-Yo's first solo, a vibrant restatement of the quiet opening theme. It was perfect, and a wave of excitement swept through the auditorium as he ended the first phrase.

His facility with the technical demands of the Concerto would have been impressive in itself. Haydn was unaccustomed to writing virtuoso solo parts since he was not a virtuoso performer himself. But this concerto, written for (and perhaps with the aid of) the principal cellist of Prince Esterhazy's private orchestra, abounds with the most difficult technical feats: monstrous intervals and arpeggios, fiendish scales, and intricate double-stop passages, all of which Yo-Yo seemed to play effortlessly.

Lynn Chang, Stephen Hammer, Richard Yoder, and Yo-Yo Ma were the the soloists in Haydn's Sinfonia Concertante in B flat. Lynn Chang glowed in the limelight, playing the violin with just the right amount of youthful schmaltz, giving the entire piece energy and impulse. In their lesser roles, Richard Yoder's bassoon, Stephen Hammer's oboe, and Yo-Yo Ma's cello blended beautifully.

Compared to the dynamic solo performances, the orchestral playing was stagnant. Bach's Suite No.4 in D lacked the pulse of the dances it represents--the Bouree, the Gavotte, and the Menuet. Baker's conducting looked energetic but the energy seemed misdirected--he failed to set a strong beat. The 99th Symphony sounded bland and imprecise, even though Baker's tempos were well-chosen. Perhaps in an effort to compensate, Baker overconducted the second movement (Adagio), and his vigorous beating clashed with the lyrical 3/4 meter.

The intonation of the Bach Society violin section is notorious, but fortunately their accompaniment in the Concertante and the Concerto was unobtrusive, if not tame. They may have been inspired by the soloists' performances. Most disappointing in the Suite and Symphony were the solos and small ensemble passages, although the flutes and trumpets were consistently good. Less rigid conducting and freer interchange between the solo musicians in these sections would have improved the situation considerably.

In spite of these weaknesses the concert was an immense success. As long as the Bach Society continues to feature soloists like the ones Saturday evening, Sanders will be sold out, and the Bach Society concerts will be enjoyable and worthwhile.