The New Secret to Online Dating Success? Your Voice

NEARLY 40 AND SINGLE, Tracy Morris had been online dating for a while, but she wasn't about to settle. Not for the man who turned out to have a whiny, mewling voice; its weak quality made her feel unsafe. Nor for the one who spoke in short, chopped, angry sentences. "Voice is a pheromone to me," said Ms. Morris, a McLean, Virginia-based interior designer. "I think it's one of the senses."