The new audio analytics are part of a suite of cross-channel measurement tools that Google is offering, principally by augmenting its advertiser "dashboard." In addition to the audio component, the new measures include a tool that allows publishers to compare their performance with other Web sites.

Google's audio ad service has struggled to attract advertisers since the search giant's acquisition of dMarc, an online audio ad placement company, in January 2006. The lukewarm response was due, in part, to a lack of premium radio ad inventory. Before Google acquired it, broadcasters mostly used dMarc's automated system to dispose of less desirable "remnant" inventory that is left unsold at the end of each business day.

To prime the pump with premium inventory, in April 2007 Google struck a deal with Clear Channel Radio, gaining access to less than 5% of its ad space under terms that were said to be very favorable to the broadcaster. However, this deal doesn't appear to have moved the needle yet, as the company revealed in its annual Form 10-K filing to the Securities and Exchange Commission, conceding that "we have yet to realize significant revenue benefits from our acquisitions of dMarc Broadcasting (Audio Ads)."

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