If you haven’t already heard the advertising blitz on your radio station of choice, you soon will. The station you are listening to wants you to know they have it. Electronics stores want you to buy it. Between the ads for the video games, restaurants and energy drinks, we keep hearing about it: High Definition Radio.Radio stations throughout Dallas and Fort Worth are beginning a transition, like their television counterparts, to all-digital content in an effort to improve the quality of their products.

As with any new technology, however, many consumers don’t know what a new product has to offer. Is HD radio really all that important?

What is HD Radio?

HD radio means two things for the average listener: improved sound quality and more choice.

iBiquity, the company that patented the technology used to send HD radio signals, heralds it as “radio for the 21st Century.” According to its Web site, digital compression makes AM stations sound like FM and FM stations achieve near CD-quality sound, all the while removing the pops, hisses and volume changes that plague analog radio.

Since the HD signal is broadcast on the same frequency as the regular broadcast, the radio can switch between HD signal and traditional analog when signal strength is weak.

For AM, the story ends here; for FM, it is only the tip of the iceberg.

The larger bandwidth on FM allows for the broadcast of surround sound music or multiple stereo radio stations on the same frequency, known as sidebands or HD2s. Current technology limits this to three stations on one frequency, but most stations stick with their main signals and one sideband since quality must be decreased to broadcast large amounts of information simultaneously on the same bandwidth.

J.D. Freeman, Dallas’ regional vice president for Clear Channel Communications, a San Antonio-based corporation that is one of the nation’s biggest owners of radio stations, said the ability to have multiple stations on one frequency with high-quality sound makes this a real radio revolution.

Freeman said FM frequencies in the Dallas-Fort Worth market are valued at more than half a billion dollars, whereas implementation of HD radio technology costs between $100,000 and $150,000. He said that, for this price, Clear Channel has put five new stations on the air this year using the HD sidebands.

All Clear Channel stations in the top 10 radio markets have been converted to high definition, with the top 150 to be completed within the year, Freeman said.

How is HD radio different from satellite radio?

Satellite radio advertising and promotion over the past few years have emphasized how listeners can pay a small monthly fee after buying a receiver unit and hear the same radio content as they travel throughout the country with little to no service interruption. From studios in New York or Washington D.C., DJs can broadcast to anyone in the country who is listening to their stations.

HD radio comes from locally based studios, but is limited geographically, just as radio has been traditionally. They must also adhere to the same decency guidelines traditional radio has always been subject to, while satellite content remains largely uncensored.

Freeman said satellite will likely have to start considering decency standards as their audience grows, but also said the v-chip could make its way to radio and change standards across the board.

“A listener shouldn’t have to worry about what their kids hear when they turn the radio on,” Freeman said, “but everyone also has their own idea of what is decent.”

Duane Doherty, program director for local classic rock station KZPS and alternative rock station KDGE “The Edge,” both Clear Channel stations, said sideband frequencies allow traditional radio to offer a wider variety of content in much the same way satellite radio can, but without the subscription fee.

“HD enables radio to ‘step outside the box’ and invent new programming and take chances that we might not have been able to do in the past,” Doherty said. “The technology and (sideband) multicast capability enables us to provide programming in a high definition signal that’s local, more compelling and exciting than satellite, and it’s free.”

While the main high definition stations are merely digital broadcasts of the same content – commercials and all – the HD sidebands are currently commercial free.

Rob Chickering, engineering manager for Susquehanna Radio Dallas, said this is a result of the way the secondary frequencies are licensed by the government.

“Currently, the HD2s are listed as experimental with the FCC and thus are required to be noncommercial,” Chickering said. Freeman said commercials will likely start appearing on HD sideband stations in the next year to two years, but they may be handled differently.

He said Clear Channel plans to change to standard length of commercials on its HD stations to 15 seconds and group them in ways that are not as intrusive to the listener.

“I don’t think people mind commercials,” Freeman said. “I think they mind hearing bad commercials and too many of them.”

Chickering said the biggest obstacle for HD radio is availability.

“Once (HD) radios start to ship in cars,” Chickering said, “(it) will become the main delivery to the listener.”

Satellite radio has made its way into many vehicles as standard or optional equipment recently. BMW, however, announced April 12 that the new iPod interface available in its 3, 5, 6 and 7 series vehicles will also include an HD receiver in addition to a Sirius satellite receiver.

What new content is offered in HD now?

Most FM frequencies, with the exception of smaller stations such as KTCU, in the Metroplex have started the switch to HD broadcasts, though most do not carry sideband stations yet.

Those stations that do have sideband frequencies vary in what they offer.

Classic rock station KZPS has “Lonestar,” a station featuring Southern rock, alternative country and outlaw country. MIX 102.9 offers a commercial-free version of the same format. Though the main frequency for JACK-FM takes no requests, its HD2 station is all request.

“The Edge’s” sideband frequency, “The Cutting Edge,” acts as a test area for new music, only airing music released since 2000.

“‘The Cutting Edge’ enables us to play styles of alternative and rock that don’t necessarily fit what we do on ‘The Edge,'” Doherty said. “Bands like Snow Patrol, Yeah Yeah Yeahs, Arctic Monkeys, My Morning Jacket and Aqualung get their start on ‘The Cutting Edge’ and can then potentially cross over to ‘The Edge.'”

Sideband frequencies are being planned for Susquehanna stations “The Wolf” and “The Bone,” but they are not yet on the air, Chickering said.