Nancy Zylstra never caught the opera bug. While majoring in bassoon at the University of Washington, she discovered a love for singing?just not in the opera style favored by the school. "I couldn't stand all that vibrato," she says. So she sold her bassoon and moved to Paris to study with a voice instructor there. And over the next several decades, she developed an international reputation as a soloist who could hit soaring high notes with a beautifully clear tone. But an autoimmune disorder made her vocal chords stop vibrating correctly. After nearly a decade of surgeries and therapy to try to get her voice back, Zylstra accepted her fate and started teaching. Though she describes herself as musically bossy and has a reputation for high standards, she doesn't limit her students to people with a degree from Juilliard. When you want to join one of Seattle's many picky Renaissance choirs and need to get the warble out of your upper range, she's the one to call. ?Laura Onstot madamenz@msn.com.