Japanese group delivers pleasant night of Bach

Bach Collegium Japan is the leading early-music ensemble in Asia and now a significant international presence because of 10 years of support from the Swedish record company BIS. Founder-director Masaaki Suzuki brought his group to Boston to perform Bach's ''St. Matthew" Passion two years ago, and they returned Saturday night for a program of Bach's instrumental music.

This was almost ''Pops Goes Bach," with such chestnuts as the B-minor Suite, the D-minor Harpsichord Concerto, the Concerto for Two Violins, and the Fifth Brandenburg Concerto. The performances were not on the superb level reached in the ''St. Matthew," but the concert certainly gave pleasure. And this is hardly the only early-instrument group to fail to reach in live performance the standards of balance and intonation documented on recordings.

Flutist Liliko Maeda is a winsome stage presence with a sweet tone, but she has problems with breath and phrasing, and the strings repeatedly and inconsiderately overpowered her low register in the suite. Violinists Ryo Terakado and Natsumi Wakamatsu played the double concerto securely but without much sense of interaction, let alone fun, and there was a lot of the now old-fashioned concertina squeeze in the dynamics. Terakado did occasionally warm up a sustained tone with a touch of vibrato, as did the wonderful cellist Hidemi Suzuki, the director's brother.

The Suzukis are by far the most compelling figures in the group. Playing on a harpsichord built by Boston's David Werbeloff, Masaaki Suzuki offered dash, style, and imagination in the harpsichord concerto, although the strings often overpowered him as well. In the cadenza in the first movement of the Brandenburg, he was on his own and displayed virtuoso command of phrase, rhythm, ornament, drama, and momentum. One would love to hear him take wing in a solo recital.