Just as one expects Midas to do more with mufflers than the neighborhood gas station, one expects a group like the Cantilena Piano Quartet to deliver superior interpretation of works in its career genre. For the most part, this was true of the Cantilena's concert at the Corcoran Gallery Friday night.

But overuse of late romantic repertoire can be hazardous to those fragile values of freshness and imagination. In the Brahms Op. 25 in G Minor, the group was able to capture but not sustain the powerful undercurrents of emotion. Pianist Frank Glazer passed over the haunting, insinuating quality of the piece's opening, hurrying into a competent but sometimes mechanical reading. Though he showed intelligence and depth throughout, he also belabored some of his phrases.

The Dvorak showed more of the group's strengths in interpretation, but also more of its weaknesses. The music's audacious harmony (for Dvorak) inspired the performers, but it also revealed their glitches as an ensemble. The rather cluttered Allegro movement did not make a strong first impression. However, in the exquisite Lento movement, the performers coaxed out a clear (but not unforgettable) profile of this music, which they sustained until the end. -- Marion Jacobson