Nielsen 250

After months of consternation and controversy, Nielsen is moving its updated PPM encoders from the lab to the market. The company on Oct. 12 will implement new Critical Band Encoding Technology (CBET) software in the Baltimore and Washington, DC markets, where it has been testing the technology, before expanding to all PPM markets in November.

The enhancements are a set of algorithm updates that Nielsen says better hides its watermarks in a station’s audio signal, allowing it to make PPM codes stronger and more robust while keeping them inaudible. “These enhancements will improve the PPM device’s ability to detect encoded audio in challenging acoustic environments such as high background noise or low volume content,” the company said Thursday in a memo to clients.

Lab tests conducted in New York simulated a variety of audio environments and measured different types of programming such as music and talk.

During a 30-minute session at the Radio Show, Nielsen chief engineer Arun Ramaswamy said the number of codes detected per minute more than doubled from one with the legacy encoders to 2.5 with the updated encoder. The enhanced encoder credited 100% of quarter hours in challenging acoustic conditions while the legacy encoders credited as few as 69% for some spoken word programming.

In addition to lab testing, Nielsen field-tested the new CBET on 19 radio stations in various formats in Washington, DC and Baltimore. Nielsen used both the old and new encoders on the stations and compared the results. The new CBET had a positive impact on audience estimates. The test stations experienced an average 15% increase in AQH persons 6+ with the enhanced encoders, which didn’t impact currency ratings. With routine ratings rounding, about 40% of the station daypart/demo cases had a 0.1 point AQH rating gain but the lift in AQH ratings was higher among persons aged 35 and older in the 6am-7pm daypart.