The Australian Navy needed to recruit Electronic Spectrum System Operators. It’s an intelligence role that’s difficult to recruit for and involves identifying threats at sea by manipulating frequencies in the electromagnetic spectrum – also known as The Invisible Battlefield. So, that’s where we ran our ad. With a small budget for social media, we created a single audio file that was so much more than something to listen to. We challenged people to analyse it, decode it, manipulate its frequency content and discover its hidden message – a poster, painted with sound.

The Audio Ad You Can See is 56 seconds of audio. But hidden inside the audio is a poster – our recruitment ad for the Australian Navy. To find it, the audio needs to be processed with a spectrogram. It’s a tool that analyses frequencies in the electromagnetic spectrum and is used by audio engineers to repair sound and remove unwanted hisses, hums, buzzes and background noise. It’s also used by the Navy to analyse frequencies at sea and identify threats that can’t be seen. Only those with the right skills and problem-solving abilities could find the hidden message and get the link to take them directly to the job listing. The result was an audio ad that was also a print ad, a social post, user-generated content, a direct recruitment campaign, and an innovative way for the Australian Navy to find its new intelligence recruits.

This audience is notoriously hard to reach. They’re interested in technology and problem-solving, so connecting with them required an idea that challenged them and invited participation. The Audio Ad You Can See did that – it asked them to roleplay as an intelligence officer and use the same technology they would in the Navy. Not everyone could find the hidden message, so we knew the people visiting the job page were high quality candidates – they had found the direct link to the website. The collection of data was a simple process in tracking downloads, streams, social interactions and visits to the job page.

This was an incredibly complex sound design challenge. While the audio needed to be crafted for an image, the image needed to be crafted for audio. So, this called for a unique collaboration between an audio engineer and visual designer. Hiding a print ad inside an audio ad began with a visual designer creating a poster. It was then converted into audio using an image synthesizer, before the voice and further soundscape elements were added. Extensive use of additive EQ, subtractive EQ, compression and the micro-automation of volume were meticulously used to ensure each sound its own sonic space in the frequency spectrum. Essentially, the audio engineer was painting with sound, designing for an image. The audio also contained other hidden sounds to misdirect the audience, like sonar pings, whale sounds, muffled communications and Morse code – with its own hidden message that spelled out ‘KEEP LOOKING’. For every audio output created, the designer then tweaked the design, which informed further decisions from the sound engineer – over 100 outputs were created before the final audio and image worked in harmony. The audio was released on social media and seeded via Australia’s top music and tech publications to reach our specific audience.

This was one of the Navy’s most successful direct recruitment campaigns. On social media, it had more interactions than any other organic post from Australia’s Defence Forces with 512% more impressions, resulting in 80 times more engagement with the job listing, all from high quality candidates. The media reach also helped position the Australian Navy as an innovative and tech-based employer for anyone interested in science, technology, engineering and mathematics. The Audio Ad You Can See gave high quality candidates an experience that went beyond listening to an ad or looking at a poster – it put them in the shoes on an Electronic Spectrum Systems Operator and helped them imagine a career in the Navy.