In almost all respects, Gabriel Van Allen is a normal 11-year-old, addicted to Kool-Aid and junk food, the Beatles, baseball and baseball cards; shyly curious about the female of the species, and inclined to track mud into the Philadelphia home he shares with his divorced mother. Only one quality sets him apart from his classmates--the way he plays the flute. "He is too much for me," his first teacher avows after nine months of lessons. "I have taught him everything that I have to teach."

When Gabriel is taken to a new teacher, Lawrence Chattarjee, who was an internationally famous virtuoso before he lost two fingers in an accident, he finds himself on the fringes of the curious world of professional musicians--a world clearly familiar to Karen Rile, who has produced a beguiling first novel while still in her early twenties. Set primarily in Philadelphia, with key episodes in New York and Chicago, "Winter Music" has a large and perceptively observed cast of characters, an intricate set of motifs and overtones, a plot that moves busily on several levels and a convincingly portrayed and detailed background.

A trained flutist, Rile wrote "Winter Music" while working as a booking agent for classical musicians. She has heeded the standard advice that aspiring novelists should write about what they know, and the result (despite some very small technical problems in the book's structure) is a highly readable, enjoyable novel that takes the reader into a small, special, unfamiliar world.

The book's dust jacket is decorated with the opening measures of Debussy's "Pre'lude a l'apre s-midi d'un faune" in the version for flute and piano, superimposed on a lighter image of a faun playing a flute. For once, we can tell quite a bit about a book by its cover. Like Debussy's masterpiece, "Winter Music" is a celebration of the flute in all its cool, graceful, glittering splendor. Like Debussy's music and Mallarme's poem that inspired it, the novel explores eros in many forms and a variety of ambivalent moods, though it avoids explicitly erotic scenes; it sets down many points with a fine clarity, but its power comes in large measure from its reticences and implications, things hinted and half-said.

In one dimension, the book is a study of innocence and experience--the passage from one to the other and, in Gabriel's case, the attempt to preserve one while acquiring the other. Gabriel's innocent adventures in sexuality and in concert life wound him. His first brush with the curious rituals of choosing a girlfriend in grammar school involves him in a fight in which one of his fingers is broken--a wound that evokes Lawrence's two lost fingers, but one that will not seriously set back his musical development. Perhaps more serious, but not fatal, is the influence of his mother, an impatient, ambitious woman who pushes him too far too fast and who is one of the most vivid characters in a book full of vivid characters.

Too full, perhaps. In her exploration of innocence vs. experience, the author examines the problems of James Rosen, the world's leading flute virtuoso, who is in his early forties and who is having his first heterosexual experience. What begins as a vaguely defined triangle evolves into a pentagon so complicated that the author finally cannot unravel all its strands without gratuitously killing a couple of the characters. But even in this episode, which might be dismissed as a miscue too hastily remedied, there is a thematic dimension. Along with the life of music and the lives of musicians, the looming shadow of death is another of the motifs in "Winter Music," and most of the time it is woven into the story with great skill.

Amid its diversity of characters, the book comes into focus around the two polar figures of Lawrence and of Gabriel's mother, Elizabeth (part of a constellation of the various mothers who constitute yet another sub-motif). Open conflict between the two is only lightly sketched until the final pages of the book, when Elizabeth, against Lawrence's advice, hires a publicist, an agent and a hall and pushes Gabriel into making a premature debut. Both Lawrence and Elizabeth have seen in Gabriel a way to self-fulfillment, but ultimately Lawrence's approach--gentler, more patient and more fully aware of the limitations and possibilities, more attuned to what Gabriel is and what he needs--is the one that should prevail. "It was a mistake that will help you learn and that will be forgotten by the public, which has a short and fickle memory," Lawrence says in an unmailed letter to Gabriel as the book ends. "I can make it safe for you to grow. When you blossom and leave me I will know that my own art is not incomplete."

If Karen Rile continues to develop from the promising beginning she has made in "Winter Music," we may have here the launching of a significant new talent.