HD Radio. Just the name conjures up images of the world of 2006. Most of us heard of HD Radio back then, and didn’t hear much after that. The technology was going to take over the world, they said; after 12 years few people are waiting for that.
HD Radio is found today in cars and few other places. It’s one of those things you generally don’t think about. Does that mean it’s going away?
What is HD Radio?
HD Radio is a trademark for a digital signal broadcast alongside a regular FM signal. When FM radio was first invented, radios weren’t as good as they are now. In order to keep stations from interfering with each other, a large area of unused bandwidth, referred to as a “white space” was used between one station’s FM signal and another. That space is actually so big by today’s standards you can fit several CD-quality streams in it.
HD radio is a digital signal, meaning it can take up less space and provide better quality than standard AM or FM. In the US, HD radio is generally used to mirror AM stations. While AM has better range, the quality is quite poor. That’s why most AM broadcasts today are mostly talk. People don’t care as much about the sound quality of talk stations compared to music stations. Still, an HD mirror of an AM signal is going to sound a lot better.
Another characteristic of HD Radio is its ability to carry “metadata.” This can be the program title or even artwork. In most cases this metadata carries information on what AM station to tune to if the signal is lost. That way, the radio can switch to AM if the HD signal isn’t available.
HD Radio is getting more important
AM broadcasting isn’t going anywhere. It’s actually part of our country’s national security plan. There are a small number of AM stations licensed to broadcast signals so strong you can get them hundreds of miles away. (You can see a list here.) These are the stations that would be used in case of national emergencies. Unless some other technology is invented that is as simple and reliable as AM, it’s never going to completely fade away.
However, HD Radio has found a home in cars and that’s where it’s going to continue to be important. An increasing number of new cars are actually being made without AM radios. Mostly it’s electric and plug-in electric vehicles, because the inverters used in such cars put out a lot of interference on the AM band. While more shielding would fix this, it seems like manufacturers don’t want expensive and heavy metal shields being added. They’d just as soon remove AM.
Without AM radio in the car, your only choice for listening to those stations is the HD equivalent. Of course some stations also do stream through iHeartRadio, Slacker, TuneIn, and other streaming sources, but not all cars have built-in cell service (few do, in fact.) This makes for an extra step when streaming from the phone.
HD Radio is, basically, AM radio for the future.
Do you have an HD radio in your car?
Look for this logo somewhere on your car’s radio:
If you see it somewhere, you do have HD Radio and you probably didn’t even realize that you’ve been using it the whole time. If you don’t, though, you probably want to look at an upgrade at some point. There are plenty of third-party audio systems that include HD Radio, and lucky for you, several of them are available at SolidSignal.com.
