It is a pity that the Kennedy Center Concert Hall was less than half full Saturday night, because it was the scene of a once-in-a-lifetime experience. Shehnai virtuoso Ustad Bismillah Khan made his first appearance in Washington and -- considering his advanced age and reluctance to travel by air -- probably his last.

The shehnai, a double-reed instrument similar to the oboe, was the co-star of the occasion. It has come a long way in the last generation, after being a folk instrument for more than 600 years. The instrument and the player have made the rise to stardom together and indeed they are almost synonymous. Bismillah Khan has single-handedly brought the shehnai through the transition from a folk to a classical instrument.

Bismillah Khan has come a long way, too, since this reviewer first heard him perform in India in the 1950s. At that time he had a tendency to repeat some improvisatory phrases--a tendency which was almost completely absent in Saturday night's performance. He was completely at home, not only in the concert hall but in the music, as he showed in his treatment of the first number, the classic Multani raga (pronounced "rag' ").

Next came a Dhun, a lighthearted tune played with superb phrasing and imaginative improvisation in the Purbi mode, followed by the beautiful Yaman Kalyan rag'. The finale was the highly popular Dhun "Dil Ka Khailona Hai Toot Gaya," which has been adapted by Bismillah Khan for film music, exquisitely chosen to leave the audience in a happy mood at the end.