The popular Web radio service Pandora announced through its official Twitter feed that it will add 15-second audio advertisments between some of the songs played.

According to the post, the company will be "extremely respectful of your listening experience" while promising "to be prudent."

The current add strategy is expected to have a minimal impact on the users, as the average visitor will hear an ad once every two hours. Still, if the service will prove to be successful, there might be some changes made in the future.

This is not the first time that the company is trying out these audio ads. Back in 2007, there was a 9-second McDonald’s ad, that users heard only once per day. At the time, users had strong reactions against the new ad policy, fearing that Pandora might be soon filled with intrusive audio advertising. "The reactions ran the gamut, from muted concern to strong condemnation. Other listeners left comments on our blog, or contributed to posts discussing the ad on other blogs. The reactions in these other forums also expressed a variety of perspectives on the issue" explained Pandora's chief technical officer, Tom Conrad, in a blog post.

Looking to keep its clients happy, it didn’t take long for the company to remove all the audio advertising from the site and turned to other ways of making profit.

Users who do not wish to hear any sort of audio ads can sign up for the company’s premium membership, which demands an annual fee of $36.