When men try to imitate the voice of a woman, they typically raise their voices to a higher pitch, and in the end, sound like men imitating women. Actually training a man to "sound" like a woman is enormously difficult and doesn't have much to do with pitch, according to a paper by James Dembowski, a researcher at Texas Tech University in San Antonio.

"While it is true that women tend to have higher voices than men, it takes much more than a high voice to make a woman sound womanly," Dembowski wrote in a public version of his more technical paper, while will be presented next week at the Acoustical Society of America's meeting in San Antonio, Texas.

Dembowski's work is based on a study of a male-to-female transgendered woman. "Following hormone therapy and render reassignment surgery, she came to the clinic interested in developing a more feminine voice," the scientist said.

He found that the woman, known as Ms. J, spoke at a high speech rate, and some research suggested that women tend to speak more slowly than men. Over six months, a team of researchers slowed her speaking down, lessened her "vocal fry" - a growling sound men often make as they drop their pitch at the end of a sentence - and worked on Ms. J's patterns of marking stress. Dembowski said men tend to stress sounds by changing the loudness of their words, while women change their pitch, or melody.

Women who want to become men don't face the same degree of voice problems because the female-to-male hormone therapy deepens the voice.

The voice isn't changed in the male to female transition, he said.

Is it possible to teach a biological male to sound convincingly like a woman?

"Yes, but it takes a lot of work," Dembowski said.

Jim Dawson reports for Inside Science News Service.