In research with “a never before seen dataset”, the research company Colourtext, has analysed 10,000 campaigns across linear, streaming and podcasts covering 615 major brands in 22 advertiser categories between 2019 and 2021. The ad copy for 13,000 individual ads between 2020 and 2022 was also transcribed, allowing for quant semiotic analysis in to different types of calls to action, selling propositions, emotive and temporal language, brand mentions and number of words used.

Across the database, the average word count in an audio ad was discovered to be 169, with finance brands netting the highest number of words on average with 180 and food & drink the lowest with 155. The data revealed that for every 10 extra words that go into ad copy, creative standout was expected to fall by 1%. Creative standout in audio was strongly linked to website visits, and “go online” was found to be a call to action used by more than a quarter of advertisers in the research.

If you compared a target word per minute in an ad of 147, which represented zero terms and conditions, to an ad with 195 words, or long terms and conditions, creative standout dropped from 39.6% to 32.9%. This translated to a modelled drop in website response rate from 1.8% to 1.3%, and the number of projected web referrals or visits went down from 598,000 to 438,000.

Through the ad transcription for 13,000 ads between 2020 and 2022, the research identified the percentage of brands using specific words as calls to action, and its prevalence amongst different categories. “Available now” was the most popular call to action with 39% of brands using this phrase, followed by “get…” with 28%, and “go online” with 26%. In retail and finance, the call to action to “go online” rose to 50%. Brands using selling propositions tended to use news and innovation as the hook (40%), followed by help and aid (34%), which tended to be used by the UK Government and charities, and guarantees and protection (28%), often used by finance and motor brands in particular. Retail, travel or motor brands were found to be more likely than food or finance brands to be using offers, sales and discounts in their audio ads to entice people.

The research also highlighted that radio was an immediate and temporal medium with 39% of brands using “today” or “tomorrow” in their ad copy, 28% talking about seasonality like Christmas or summer, and 25% speaking about specific months of the year. Another element pulled out by the linguistic analysis was the quality or emotional tonality of language, as 60% of brands use “boosters” or “maximisers” in their copy like “the best”, “greatest”, “biggest”, “fastest”, “smoother”. A third of brands spoke to how much consumers would “like or enjoy” the experience of their brand, while under a quarter told consumers “you must” do something and 17% used the phrases “pretty good” or “incredibly good”.

‍