


Will Farrell-Green, a senior director at Audible, said in an emailed statement that the company uses automated and manual processes to enforce its rules but that “due to the volume of content on our service, titles that are not compliant do slip through from time to time.” Audible’s “human’s only” policy dates back to at least 2014, when synthetic voices were much less convincing, and the company has said the rule helps provide listeners the performances they expect. Speechki says it recommends publishers identify that narrations are synthetic and that it informs them of Audible’s policies.

“My intention was never to upset or offend anyone,” he says. Richter says he chose an artificial voice because the concept and its “uncanny valley” sound suited his book, which has a piece of intelligence software as one of its main characters, and that he was unaware of Audible’s policies. It made giveaway mistakes, like pronouncing Covid as “kah-viid” when referring to the pandemic. To Miller’s surprise, he found that “Smith” voiced a total of around half a dozen on the site from multiple publishers-breaching Audible rules that say audiobooks “must be narrated by a human.” Although “Smith” sounded more expressive than a typical synthetic voice, to Miller’s ear it was plainly artificial and offered a worse experience than a human narrator. Richter’s book listing on Amazon’s Audible credited that voice as “Nicholas Smith” without disclosing that it wasn’t human. But in December he briefly turned online detective after he saw a tweet from UK sci-fi author Jon Richter disclosing that his latest audiobook had no need for the kind of artistry Miller offers: It was narrated by a synthetic voice. Over the past two years, audiobook roles, like narrating popular fantasy series He Who Fights With Monsters, have become Miller’s main source of work.

To deliver his best performance, he takes notes on each character and any hints of how they should sound. When voice actor Heath Miller sits down in his boatshed-turned-home studio in Maine to record a new audiobook narration, he has already read the text through carefully at least once.
