After 11 years of aiding performers in their animation of opera characters such as Madame Butterfly, Otello and Don Giovanni, Beckie Kravetz decided to take matters into her own hands. Literally. As resident mask-maker, makeup artist and assistant wig-master of the Los Angeles Opera, she spends half her year immersed in Sturm und Drang. Her off-season months are devoted to her sculpture. This spring the worlds collided and produced “Sculpted Arias,” an exhibition of portrait masks of opera characters that will be on display Sept. 9-27 at the Los Angeles Music Center.      “As a makeup artist, I have to work with the face I’m given,” says Kravetz, 39. “These are my ideals. I wanted to explore the characters the way a singer would.”      The result is 11 sculptures wrought from materials as diverse and expressive as the characters they represent. “Otello is in bronze,” she says, “to represent his solidity. The Queen of the Night is enamel because she is cold and lovely. And Madame Butterfly is rice-paper delicate and easily torn.”      The Sculptures do more than bring a character vividly to life—they comment on the themes of each opera by exploring what lives behind each mask. Madame Butterfly’s face conceals a collection of Japanese butterflies; behind Don Giovanni’s visage lurks a miniature shooting gallery of women; and the bronze of Wotan contains a miniature Valhalla.      The free exhibit will be open to the public during performances and by appointment. --Mary McNamara      A reception with Kravetz will be held Sept. 17, from 7:30 to 9:30 p.m. For more information, call (213) 972-7219.