MONGOLIAN ENSEMBLE AT BECKMAN

Sinuous, sinewy yet sharply accented by rhythmic flicks of the hands or shoulder shimmies, the dances of Central Asia offer a beguiling fusion of nonstop movement flow and an insistent, invigorating pulse. Further East, the harsh contrasts of climate and landscape are reflected in other, bolder unions of opposites--qualities vividly evident in the performance of Mongolian music and dance presented in Beckman Auditorium, Caltech, on Tuesday.

The program represented a new coup for the Asia Society: the first visit to the United States by artists from the Mongolian People’s Republic. And it was adroitly organized: brief tastes of exotic instrumental, vocal and terpsichorean specialties followed by longer samplings after intermission.

In Dashjamts Nyamtsoo, the company boasted a dancer who could unleash galvanic limb and torso spasms while keeping her head absolutely still; who could intricately ornament the horse-head fiddle accompaniment with her delicate wrist-bells; who could effortlessly twist, stretch and bend into positional extremes as if all the laws of balance had been repealed.

Even so, Mongolian music may have been the great revelation of the program. Early in the evening, Shagdar Dashaa played a lyrical tune on the tsuur , an ancient flute producing both a conventional reedy tone and a deep, buzzy sound that almost seemed to come from a second instrument.

This sense of two distinctive timbres layered together also occurred in the humorous duet for mouth harp and brass trumpet by Oidov Volodya and Dashaa. But its most startling expression came in the singing (crooning, really) of Davaa Tserendavaa.

The basic sound of Tserendavaa’s voice hovered halfway between the lower range of the tsuur and the cry that a house cat makes when impatient for dinner. At the same time, he produced a high, whistle-like tone--and sustained this amazing double-edged voice through long folk songs as if it were a plaintive wind instrument.

Except for Tserendavaa, the eight artists in the company are all members of the Mongolian State Folk Song and Dance Ensemble. Whether or not they always perform in such spectacular costumes--or always venture such short pieces--their warmth and skill made many new friends on Tuesday.