Last night's recital at the Organization of American States by cellist Charles Curtis was a rare muscial treat for those few whose wisdom brought them to the Hall of the Americas.

Only 19 years of age and blessed with the looks of a matinee idol, Curtis plays with the warmth, intelligence, and often the mature, emotional integrity of cellists much older than he. It is no wonder that Curtis was the 1978 first-prize winner in the Johann Sebastian Bach International Competition for Violinists and Cellists -- the first time that competition awarded prizes in string playing.

Naturally enough, Curtis played Bach -- the E flat solo Cello Suite -- one of the two pieces that secured the first prize for him last year. s

But he also played some American music -- two very beautiful works that are seldom heard: Samuel Barber's 1932 Sonata and William Schuman's brief but highly charged "Orpheus With His Lute" from 1944. He brought his musicianly heroism to the broad singing lines in the Barber, while in Schuman's miniature essay be allowed the cello to sing mournfully.

Of course it was Bach that many wanted to hear, and Curtis' performance of the E Flat Major Suite was youthfully clean, articulate and nearly magisterial. In the Sarabande movement, he approached that silvery, swelling intensity and elevated style associated with Rostropovich.

With his elegant phrasing and strong left arm he etched a performance of a two-movement sonata by Luigi Boccherini that was in every respect cut from velvet.