UC creates voice-coaching app for gender expression

The open-source app TruVox allows people to practice speaking exercises while visualizing the components of speech such as pitch to help them speak in a convincing way that matches their gender expression.

“I think your voice reflects your self-perception — not just for transgender people,” UC Associate Professor Vesna Novak said.

Novak studies intelligent technologies to improve human health and wellness in her electrical engineering lab in UC’s College of Engineering and Applied Science. This includes rehabilitation robotics and other assistive technology.

“When we interviewed people before making the app, a few people who weren’t transgender said they didn’t like the sound of their voice,” she said. “They would say, ‘I wish I could make my voice higher or more feminine.’ But people aren’t aware that’s something they can change.”

While some people might pay to hire a speech coach, the app is available at no cost. And since it was created by a Research-1 university, users can trust it’s secure and that neither their voice nor data will be exploited.

And ensuring privacy was paramount, she said.

“Is my data being harvested for some purpose? Will someone make fun of my voice on the internet? These are legitimate concerns,” Novak said. “People can get demotivated.”

“The acoustic analysis was not the hard part,” Novak said. “This is engineering married to applied psychology.”

Novak started with the understanding that many or even most people cringe at the sound of their own speaking voice and don’t want to hear it played back to them. There’s even a phrase in psychology for this reaction: voice confrontation.

We pick up clues about gender based on several characteristics of voice, including volume and resonance, Novak said.

“Pitch is the one everyone understands,” she said.

The app offers several exercises, including a reading task to introduce users to the app. It tracks the changing pitch of the user’s voice in real time with scrolling purple dots that appear on a hertz scale that measures frequency.

Undergraduate student Mary Wilkens in UC's College of Allied Health Sciences is working on related gender-affirming voice research to explore how speech and voice characteristics influence gender perception. 

It’s fun to see the display roll across the screen like a rollercoaster as you manipulate the pitch of your voice higher or lower. The app measures 100 to 300 hertz (cycles per second), the typical frequency range of speaking voices, providing real-time feedback.

A “stair” exercise allows users to try to match their pitch to particular frequencies while repeating phrases such as “drum and bugle corps” or “bigger and better.”

Another exercise helps people practice matching the pitches of actual voices while saying phrases like “bacon and eggs” or “cheese and crackers.”

It’s harder than it looks, but Novak said that’s the point. The human voice is complex and one of our most profound means of interpersonal expression.

Practicing on the app could help people avoid being misgendered by strangers during their daily routine, Novak said. The app also could have practical benefits for people facing real danger from transphobia. Transgender people are four times more likely to be the victims of violent crime than cisgender people (those whose gender identity matches the sex they were assigned at birth).

Novak plans to present the app this month at the 26th International Conference on Human-Computer Interaction. And she plans to add new features to address other gendered aspects of human voice such as volume and resonance.

Featured image at top: UC Associate Professor Vesna Novak developed a new app to help people match their voice to their gender expression. Photo/iStockPhoto