CRITIC'S NOTEBOOK
Sound Is the Driver in a Race for Death by SARAH BOXER</b><br /> CAMBRIDGE, Mass. — It's not every day that you can step into the same plot twice. "The Sound of a Voice," a new opera with music by Philip Glass and libretto by David Henry Hwang, presented in a premiere by the American Repertory Theater at the Loeb Drama Center here, is a twice-told tale.