Inside digital audio’s media measurement challenges, both major and mythical

And it’s no wonder: more people are tuning in. Per a 2022 Edison Research survey, 73% of the US population aged 12 and older – an estimated 209 million people – listen to digital audio monthly, up from 68% in 2021; 67% listen to digital audio weekly, up 62% year-on-year.

Music streaming platforms and podcasting networks offer valuable opportunities for brands to reach target audiences in powerful, consistent ways. But among many advertisers there is still hesitance – much of which stems from a lack of confidence in audio channels’ measurability.

“Studies have shown that one of the reasons that advertisers have held back on digital audio is a lack of measurement solutions to help them understand and justify their investments in this space,” says Khurrum Malik, head of advertising business marketing at Spotify. Dedicating ad spend to channels where performance data and real outcomes are murky can feel like a wasted investment.

Digital audio’s measurement maladies

There are a number of issues at play when it comes to getting an accurate, precise, reliable and comprehensive picture of ad performance in digital audio today.

1. Trying to retrofit digital models

For one, while audio advertisers are increasingly viewing audio media planning, buying and measurement in the way they view traditional digital media, digital measurement as a field was built for visual content. Core measurement tools focus on viewability and whether a user ‘dwelled’ on an ad visually. “None of these approaches fundamentally work for measuring audio media,” says Malik.

Malik isn’t the only one who’s made the observation. Ashwini Karandikar, executive vice-president of media, technology and data at industry body the American Association of Advertising Agency (4A’s), echoes the sentiment: “What are you really measuring? Who’s listening? What are you watching?”

She suggests that these issues are similar to those reflected in connected TV (CTV) and streamed video, a sector that is itself undergoing a reckoning over ad measurement. “[This is similar to how] streaming video has sort of muddied the water around measurement overall. The same sort of questions are happening on the audio side.”

2. Connecting the dots

The core objectives of audio advertising can also raise the stakes from a measurement perspective. For instance, marketers often use audio as a medium for branding. And although branding measurement is fairly well-established and reliable in streaming audio today, connecting the dots afterward can prove challenging. “Linking the impact of brand advertising to short- and long-term sales is always a challenge – and brand marketers also have to be able to prove out value,” explains a spokesperson for Amazon Music. “So while this challenge isn’t unique to audio, it becomes more salient given audio campaigns are generally aimed at driving branding and awareness.”

Getting a grasp on other key performance metrics such as conversion can also be a headache. Conversion has historically been calculated via last-touch attribution models, which may undervalue the impact of audio in driving audiences’ consideration of conversion actions.

3. A fragmented ecosystem

To complicate matters even more, digital audio splinters out into digital radio, social audio, contextual ads in music, contextual ads in podcasts, audiobooks and more – not to mention the slew of corresponding visual and video ads that might run alongside a given audio ad. Plus, audiences may be listening across a range of devices: through their car speakers, on a desktop, on mobile or through connected home devices such as Amazon Alexa products.

“This web of media formats and publishers means that digital audio has a unique ecosystem that separates itself from the more traditional visual formats,” says Malik. Taking a snapshot of the entire picture of performance becomes nearly impossible – so measurement firms take up the task of trying “to bite off a piece here and a piece there.” As it stands, he says, no player has yet been able to offer “a holistic solution.”

Of course, each digital audio format within this web presents its own unique challenges and opportunities. The burgeoning world of podcasting, for example, comes with different measurement hurdles than streamed music, due to standard methods of delivery. “Unlike streaming ads, the majority of podcast ads are delivered with the faintest of signals back for measurement,” says Malik. “We don’t really have a way to ‘communicate’ with the ad the same way we do in other forms of digital media. This makes measurement much more complicated and somewhat less precise than we are used to elsewhere in digital media.”

It’s not all bad news for podcast advertising though. The space is becoming something of an innovation lab where publishers and third-party measurement firms team up to experiment with new approaches. At Spotify, Malik’s team takes the platform’s scores of first-party data to develop new types of inferential modeling, which could lay the groundwork for more comprehensive podcast ad measurement down the line. Plus, earlier this year, the streaming giant acquired two podcasting tech companies, Podsights and Chartable, that the company hopes will respectively help improve attribution in digital audio and improve overall insights for publishers.

How top digital audio platforms are managing

In a piecemeal environment riddled with technical challenges, major platforms and publishers have been forced to get creative.

The first player to publicly team up with a third-party measurement partner was Apple Music, which in 2019 saw publicly-traded music industry-focused linking and analytics platform Linkfire integrate its post-link-click streaming data into the popular platform.

Now, most of the industry’s top players have adopted something of a hybrid approach like that of Apple Music: they build out their own internal tools and teams to offer measurement solutions to brands, while partnering with third-party providers to fill in the gaps where needed.

iHeartMedia, one of the US’s largest traditional radio broadcasters and the country’s leading digital radio company, invests major resources in its in-house measurement capabilities. Using a variety of tools including classic pixel-based solutions like those used across the digital media ecosystem, the company can help advertisers measure attribution and ad effectiveness for digital audio buys. Plus, through a proprietary analytics platform, iHeartMedia advertisers can also gain insights into what’s working and what’s not. They can set specific key performance indicators, from web traffic to sales, in order to optimize their campaigns moving forward.

The company also works with a handful of external partners, including Claritas and Neustar, to provide deeper and more comprehensive measurement solutions.

iHeartMedia’s general manager and chief product officer Brian Kaminsky, for one, is confident in the company’s efforts. “It’s a myth that audio is not measurable. Some of [that notion] was truer in the past certainly than it is today. It may be still true for some select radio companies and for some podcasters, but not for iHeart. We’ve built this set of tools and this platform that we work on, and it really has enabled a tremendous amount of insight and confidence in our customers.”

Amazon Music is at a distinct advantage in that its parent organization is of course the largest e-commerce company on Earth. As such, while it offers standard metrics to audio advertisers, such as unique reach and frequency as well as total impressions, it’s also able to provide custom metrics for brands that also sell products and services via Amazon, explains a company spokesperson. These include product page views, branded searches and total ad-attributed purchases. The company also offers a self-service brand lift survey tool via Amazon Shopper Panel that enables advertisers to assess how specific campaigns affect purchase intent and brand awareness.

Meanwhile, Spotify, the market leader in music streaming and podcasting, utilizes a suite of first- and third-party tools, all of which have, according to Malik, been tailored to address the unique needs of digital audio advertising (rather than retrofit from traditional digital). For both music and podcast media, the platform can help advertisers measure reach, resonance and reaction, helping advertisers understand how specific audio buys impact performance.

Malik believes that providing advertisers with a mix of owned and contracted measurement services instills confidence: “Ultimately, advertisers want measurement choice and options – media ecosystems should provide a range of first-party and third-party measurement solutions to drive more transparency and accountability.”

And he’s bullish on Spotify’s future as a trailblazer in audio media measurement – in large part due to the deep first-party data insights it has on its 433m global monthly active users (188m of which are premium subscribers). “Spotify’s logged-in audience data holds one of the keys for the future of audio measurement,” he says. “Due to both our scale and the depth of information we can glean about a listener, we believe that information collected on our platform is invaluable in connecting a user’s behavior to a media impression.”

If digital audio faces ongoing ad measurement woes, leading digital audio platforms remain optimistic no less. “From [an independent] bike shop measuring their web traffic, e-commerce sales and the number of people in the store on the days they’re running media, all the way to the most sophisticated media mix models from the Procter & Gambles of the world, audio is highly measurable,” says iHeartMedia chief marketing officer Gayle Troberman. When it comes to audio, she says, ”prices are more efficient, typically, than video and [advertisers] can get a lot more reach and even more frequency for the same price. So they tend to see immediate, big lifts in ROI.”

For more on the power of sound, check out The Drum’s Audio Deep Dive.