Meet the woman whose voice you hear when using Google Maps

Karen Jacobsen, an Australian national, has been a voiceover artist for more than 20 years. [Courtesy of Great Big Story]

A journey that started nearly 21 years ago for Australian voiceover artist, Karen Jacobsen, has seen her become one of the most constant features in vehicles world-over.

The voice of Jacobsen, who is in her fifties, is used in Google Maps and other GPS apps to help motorists find their way around routes they are unfamiliar with.

To date, more than one billion Google devices have been installed with the Maps feature, making Jacobsen to jokingly state she is "the only woman who men take command from without questioning".

"I am known as the only woman men would take directions from," Jacobsen told London-based documentaries company Great Big Story.

She said she was approached by GPS maker Garmin in the early 2000s to be a voice over artist for the Google Maps feature. According to her, her Australian English accent was the most suitable for the role because "it is pleasant to listen to".

"My speaking voice ended up in over a billion GPS and smart phone devices giving direction to people around the world. [It's me who says] 'you have reached your destination'," Jacobsen told the Great Big Story.

But who is she exactly?

"I'm originally from Mackay, which is a town in North Queensland near Australia's Great Barrier Reef. I wanted to become a professional singer and move to America, and I did follow that dream to New York," narrated Jacobsen.

"Not long after I moved there [in 2002], there was an audition [for voiceover artists], and a client was looking for a native Australian, female, voiceover artist living in the northeast of the United States. [I realised I met all the qualifications]. I, therefore, went for that audition and got the job."

The voiceover artist, who dabbles in music, says her native Australian background gave her an edge over her competitors.

"At the time, I was told that the Australian voice was a high priority because the Australian accent was considered the most pleasant English-speaking accent to listen to, which is pretty cool," she said.

Jacobsen said she was first asked to record generic traffic terms before her voice was later synthesised for roads and streets that weren't originally mentioned in her script.

Voice synthesis is the artificial production of the human voice, which can be used during text to speech conversion.

"There was a huge script, a massive script! The team of engineers had figured out every combination of syllables possible for me to record, which allowed them to create the GPS voice based on my speaking voice," she said.

"Some of the phrases I recorded include: 'at the next intersection, turn left'; 'at the roundabout, turn right'; 'you have reached your destination'," added Jacobsen.

During recording, she said she was asked to repeat the word "approximately" 168 times in a row for the GPS engineers to get the perfect voice.

The Google Maps word that some motorists appeared not to like is "recalculating" because it comes across as "condescending".

Jacobsen disagrees: "It's not meant to be condescending. It's meant to be reassuring and will get you back on track," she said in a 2010 interview with CBS.

Jacobsen said using her voice has been "fun", and that she is happy she will be a constant feature on mobile phones for many years to come.

"My voice is gonna live on forever, while the power is gonna go to my head, I feel like it's mind-blowing," she told Great Big Story.

In the CBS interview, she said: "I feel very popular! I always wanted to be popular."

It was not revealed in either of the two interviews the amount of money Jacobsen, a mother-of-one, received as payment for her voice.

Jacobsen's voice has also been used in Apple's virtual assistant, Siri, which uses voice recognition to respond.

Ironically, Jacobsen struggles using Siri as the system doesn't understand her own voice.

"My husband can ask her (Siri) a question, my son can ask her a question; they get answers but when I ask a question, she doesn't understand me. We've experimented over and over but it is just the weirdest thing," she told The Daily Telegraph.

"I don't think it is because I don't speak clearly, I have very good enunciation. I just find it absolutely perplexing," she added.

Jacobsen has also tried her hand at music as a singer.