Unlike the mandatory conversion form analog to digital TV in February 2009, there is no cut-off for analog radio as the industry introduces digital HD Radio. That and fairly high prices for radios have slowed adoption, but now the industry is hoping for increased sales with lower cost radios, according to Investors Business Daily.

The conversion has been glacial, but now that HD radio receivers are available for as low as US$79, the industry is hoping that interest will pick up.

The advantages of terrestrial HD Radio include the fact that, unlike satellite radio, once the customer buys the radio, reception is free. HD radio on the FM band is static free and sounds as good as a CD, and listeners can tag songs they like for later review in Apple’s iTunes.

"We’re converting an industry that’s been around for 100 years and there are a billion radio receivers in this country, so that conversion obviously isn’t going to happen overnight," said Bob Struble. Mr. Struble is the chief executive of iBiquity Digital, which developed the standards for HD Radio and has worked with Apple to develop the iTunes tagging feature.

HD Radio is now broadcasting in most major U.S. cities, and there are now about 60 HD Radio receivers on the market from Sony and Harman International available at Best Buy, Circuit City and Wal-Mart. BMW, Ford and Hyundai have started installing HD Radio receivers in their cars.

About 300,000 HD Radios were sold in the U.S. last year, compared with a total annual analog radio sales of 70 million. "Clearly to be in the mass market we need to be selling in the millions," said Mr. Struble. "And we’re working to get there."