That goes for technology like video games, too: “Poor voice acting will break immersion far more quickly than bad graphics,” says the University of Utah’s Altizer.

And the same danger even rings true in the corporate world. “When they do a project, they become that audio ambassador – they become the voice of that company,” says Voices.com’s Ciccarelli. “There’s a responsibility. We associate a brand with a particular voice.”

But for many voice actors, they’re well aware of the responsibility – and well aware of the very real, deep bond they develop with their audiences, too.

Paulsen speaks about meeting fans at conventions who say Ninja Turtles got them through their parents’ divorce, or the Iraq vet whose fallen comrade loved Pinky and the Brain. “I never in a million years would have known that, ever.”

It even affects voice actors themselves when they meet voices from their own childhoods, like when Tara Strong says she sang in The Little Mermaid 2 with Jodi Benson, the original Ariel.

“I burst into tears when I met her,” Strong says.

To be sure, each work is the product of multiple talents, from animators to writers to musicians and more. But there’s something about voices people can’t seem to forget.

“When it’s done correctly, it’s the best of all worlds,” Paulsen says. “It connects with people on a deep level, it gets them through difficult circumstances, it reminds them of their childhood, they’re able to share it with their own children. It never gets old.”

It seems that, regardless of technological advances and complications in industries, the power of the human voice holds strong.

“What makes voice unique is that it is genuinely human,” Ciccrallei says. “It’s not an extension of yourself. It is yourself.”

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Bryan Lufkin is BBC Capital’s features writer. Follow him on Twitter @bryan_lufkin.

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