HEARING was believing at the 25th Swindon Festival of Literature yesterday.

Professor Trevor Cox kicked off the second day of the festival with an engaging and fascinating talk at the Arts Centre about the history of vocal communication.

Trevor talked about how how new technology like Amazon’s Alexa and software that can use recordings to create convincing fake voice samples are changing the way we speak to each other.

His talk also touched on the various, often misguided, prejudices and preconceptions that we subconsciously make based on the tone and pitch of other people’s speech.

Professor Cox said: "We are social animals, we pick up on cues which tell us where you're from and how you're feeling.

"Our voice betrays a lot about us but sometimes we misinterpret these cues and get the wrong impression, this leads to stereotyping and prejudice.

"The problem is that we are going to end up putting these biases into the AI we create.

"Women's voices became lower in pitch during the latter half of the twentieth century, when more of them achieved positions of leadership, which is a very male-dominated area.

"It was found that women in these positions often lowered their voice to fit in and because,.unfortunately, women using their normal pitch when speaking weren't considered authoritative."

Such nuggets of scientific trivia provoked murmurs of astonishment, while a clip showing the fleshy vocal folds inside the throat of a trained singer as she belted out a few high notes caused a few gasps of amazement and revulsion.

There was also time for some light-hearted debate about pronunciations of words like 'scone;', how they can vary across the country, and how they've changed over time.

After he was done dishing out mind-blowing facts and curious quirks about speech, he took questions from a keen audience of festivalgoers.

Trevor was in town to promote his new book, Now You’re Talking: The Story of Human Conversation from the Neanderthals to Artificial Intelligence.

He stayed to sign copies and chat to inquisitive audience members after the event, and spoke briefly to the Adver about how he became a Professor of Acoustic Engineering.

He said: "I started out in physics and moved into acoustics.

"I designed theatres and looked at how the shape of the building affected the vocals and music being performed, and worked on improvements to the acoustics.

"After all, if you can't hear what's being said onstage in a theatre, then it's clearly been poorly-designed.

"I've always been fascinated by sound and going into this profession gave me a good excuse to spend a lot more time learning about voices than I would otherwise have been able to."

Later that day, author Gill Sims gave a talk about parenting and her book Why Mummy Drinks.