Audio advertising has a scale problem.
While Spotify, Pandora and iHeartMedia dominate industry attention, roughly half of the ad-supported audio market sits outside those platforms.
Hundreds of streaming audio publishers, podcast creators and niche content providers are competing for advertising dollars without the sales teams, audience data or measurement capabilities needed to consistently attract large media budgets. Which means this inventory often goes overlooked by audio advertisers.
Harnessing this untapped scale is the opportunity DAX has spent the last decade pursuing.
The audio SSP and sales company works with audio publishers on both the buy side and sell side, helping them monetize audiences through direct and programmatic demand while attracting new listeners to their content.
But DAX’s broader challenge reflects one facing the audio industry as a whole: proving that fragmented audio inventory can deliver the scale, measurement and outcomes advertisers increasingly expect.
Solving for scale
Through its growing audio publisher network, DAX has already addressed the scale part of the equation.
“We have 40 million monthly uniques that are exclusive to DAX,” said Brian Conlan, president of DAX US. “We have access to over 100 million uniques combined in our audio SSP, and we reach roughly 80% of the US audio landscape.”
Still, despite the reach that can be achieved by combining smaller audiences, attracting advertiser attention remains difficult for many independent audio publishers.
Large agency buyers often know the biggest audio platforms, Conlan said, but smaller publishers can struggle to communicate the value of their audiences.
“The holding company buyers probably don’t know what Deezer has in the US,” Conlan said, referring to a streaming music publisher the SSP works with that boasts more than 10 million US unique listeners. “They just know the big three or four in the space that they see sales teams from every day.”
That visibility challenge is one reason publishers like AccuRadio work with outside sales partners like DAX. The streaming service operates more than 1,000 human-curated music channels, but it has no internal sales team, said Jim Pavilack, head of strategic partnerships at AccuRadio.
Instead, the company relies on DAX and other partners to bring its audience into agency conversations. “They’re in at all the agencies, and they have a lot of direct relationships,” Pavilack said.
The challenge, though, isn’t simply selling one undervalued publisher’s inventory. Advertisers increasingly want large-scale audience buys rather than publisher-specific deals, which means audio sales companies like DAX need to package fragmented inventory into broader audience segments.
Making measurement work
Although scale helps get audio onto a media plan, measurement determines whether those budgets return.
Advertisers are demanding more evidence that audio campaigns are driving outcomes rather than simply generating impressions. So audio sales houses have to prove it.
According to Talkspace, an online therapy and telehealth app that works with DAX as a buyer for its customer acquisition campaigns, measuring the impact of digital audio ads is more complicated than it is for other channels like social media.
Part of that complexity comes from having to combine publisher inventory to achieve scale – and then having to measure ad impact across different inventory pools. For that reason, digital audio is “a little bit more fragmented when it gets into the measurement frameworks compared to some other direct-response channels,” said Melissa Velasco, director of growth marketing at Talkspace.
To stitch together a picture of how podcast campaigns influence consumer behavior, Talkspace uses a mix of attribution tools, survey responses, brand-lift studies and incrementality testing, Velasco said. Talkspace also works with DAX to gain additional visibility into campaign performance across its audio buys.
Publishers are seeking similar transparency on the sell side. AccuRadio’s Pavilack said better visibility into campaign performance has become increasingly important, as advertisers ask more detailed questions about audience engagement and outcomes.
That emphasis on outcomes reflects a broader shift across the industry, according to DAX’s Conlan. It also makes it easier to sell buyers on inventory that demonstrably drives outcomes.
“I’m a big proponent of measurement on every campaign,” he said. “If you tag it and it performs, we deserve a seat at the table.”
However, the industry’s growing focus on accountability is also exposing some gaps in audio measurement. Conlan pointed to smart speakers as one area where listener consumption has expanded rapidly but measurement capabilities have lagged behind. “That’s a little bit of a black hole in the audio landscape,” he said.
From show buys to audience buys
While measurement remains a challenge for the audio space, many advertisers face a more immediate problem: scaling successful podcast campaigns.
Part of podcasting’s scale challenge comes down to what inventory tends to perform well in the podcast market. Velasco said host-read podcast ads tend to perform best for Talkspace because listeners trust the host’s voice, and the ads feel native to the show.
But that authenticity is difficult to scale. Historically, advertisers seeking host-read ads have had to work directly with creators or podcast networks to produce those spots, limiting how quickly campaigns can expand. And, if you’re working with a few different podcasts to achieve a certain level of reach, that means striking numerous direct deals with a variety of hosts.
For Talkspace, that challenge led the company to test DAX’s Premium Podcast Network, which uses Frequency’s workflow automation technology to distribute host-read ads across a broader network of podcast creators.
“We’re still getting that host-read quality and authenticity with an engaged audience and listener base,” Velasco said. “But we’re able to expand that out and get more reach across a variety of different shows.”
A recent Talkspace campaign run through DAX’s Premium Podcast Network also produced an unexpected insight. While mental health and wellness podcasts appeared to be a natural fit for Talkspace, some of the company’s strongest-performing placements came from unrelated genres, Velasco said.
The finding reinforced a broader trend Conlan sees across audio advertising: Buyers are increasingly targeting audiences rather than content categories.
With that in mind, he said, digital audio targeting is no longer simply about curating contextual inventory; it’s about proving which audiences perform, then making that inventory easier to buy, measure and scale.
