I'm sure everyone has heard the hype on the radio about HD radio. So, what's the hubbub, bub?
WNRN has put up a FAQ about HD radio. Pretty interesting reading.
WNRN has put up a FAQ about HD radio. Pretty interesting reading.
Have you heard about digital radio? It's actually been around for almost a decade....After a long period of relative non-interest, the folks pushing it decided to try coat-tailing TV by adopting the "HD" moniker. It is still the same highly flawed technology as the "digital radio" that got 15 seconds of mainstream media attention when the FCC approved it years ago, just with a new name.
Here's a Q & A, starting with the basics for the casual listener, and more details for the more avid listener or audiophile follow the "short" answer.
Q: Does "HD" Radio sound any better than analog radio?
A: No. While HD TV looks MUCH better, and sounds somewhat better, with the capability to broadcast in surround formats, HD radio is highly compressed, low-bit rate audio which sounds about the same as Satellite or Internet radio.
If you're an average listener with an average sound system, you may hear NO DIFFERENCE at all. If you have good ears, and a good sound system, it is obvious that the sound quality is inferior to CD's, and good sounding analog FM. (It may sound substantially better than many bad sounding analog FM stations, however ---of which there are many, esp. in the Charlottesville area.).
Q: Does an "HD" station sound better on a normal radio?
A: No. The two audio streams are unrelated.
Often a station that "goes HD" will install new equipment, or adjust and calibrate existing equipment (sometimes for the first time in months, years....or decades, so it might sound different. This could mean better sound, but not always. Some HD broadcast methods and equipment, if not carefully adjusted, cause weird birdies and buzzes under the audio. That is going on at one C'Ville station now.
Q: Does it have better coverage?
A: No. In fact it's coverage is a fraction of traditional coverage, but "HD" radios will revert to the analog when the digital fails.
For high-powered stations in big cities (the focus of this technology) it may mean 20 miles of coverage instead of 50. For low-powered stations in rough terrain, the uninterrupted digital coverage is negligible. Despite the utterly false claim by one Charlottesville radio station, that it is first to have a digital signal on the air ( 10/08), NPR on 89.3 & 88.5 have been "HD" for several years. It is hard to drive more than a few feet with it without reversion to analog. At home, with sufficient antenna, it should be some better, though (to WVTF's knowledge) there are no confirmed HD listeners in the area.
Q: Can it broadcast additional programming?
A: Yes. However to support so-called HD-2 & HD-3 programming, the bit-rate for the main channel must be reduced, thereby degrading its quality further. Most significantly, these lo-fi "sub-channels," obviously have no analog to which they can revert when the digital fails. For low-powered stations, these sub-channels are mostly worthless.
Q: What is HD's carbon-footprint impact?
A: It is increased markedly.
The technology used to "attach" the digital carrier(s) +/- the station's main carrier frequency (the number you associate w/the station, e.g. 91.9, 88.5, etc.) is extremely inefficient. Though it varies from brand to brand among equipment manufacturers, the method the station chooses to use for digital transmission, and the station's analog power, utility requirements increase from the 50% to several-hundred percent range.
One Charlottesville station that promotes itself as "green" (because the sampler CD it gets from its corporate headquarters comes in a cardboard box) is using way more electricity than it otherwise would to broadcast "HD," although it isn't clear that any "HD" radios are in service in the area. In the nearly 4 years that NPR has been HD in C'Ville, the station broadcasting it has received one phone about it (as of 10/08): It was a complaint from
Scottsville that it could not be received consistently. The electricity for HD is obviously being totally wasted.
Q: Why is this technology available and spreading (to the extent that it is)?
A: Corrupt influence and politics. Broadcast equipment makers are salivating over selling every broadcaster in the country $100,000+ of new gear, despite the fact that it doesn't really have any real benefit. It goes far deeper, however....The lab pushing the system is called "Ibiquity." It is owned by Clear Channel, who's top people are all buds with a certain former Texas governor who's been in charge in DC for the last 8 years. These people convinced the FCC to approve (for the first time in history) a non-"open-source" transmission method. This means that everyone broadcasting in "HD" must send Ibiquity a check every month forever. (The analogy would be that if every FM Stereo station had to send Zenith a check every month because they invented the FM-Stereo system.) (There's no business like getting all your competitors to mail you money!)
In order to "seed" the industry, Clear Channel is using HD on all or most of their stations, and has used congressional influence to get the Corporation for Public Broadcasting to buy HD systems for all NPR stations, who were more the happy to get new transmitters and associated equipment. (The stuff will all still work fine if/when HD radio goes the way of AM stereo and "quad.") The government arranged to get their Ibiquity fees paid too!
Non-Clear Channel, non-CPB supported stations broadcasting HD are rare. Some high powered, but small-market stations own the gear but aren't using it for lack of listener and utility bill reasons. Some stations believe there's a hype-value in it; there might even be a few around who think it's going to take off someday. If car-makers are not convinced, the technology is going nowhere. Note that while car-makers have cut deals with the XM-Sirius Satellite monopoly, none have made any major commitments to this silly, Rube Goldberg HD system. (as of 11/08)
Q: Is real "HD" radio possible?
A: Yes. In fact the Ibiquity system in NON-HYBRID mode (no analog) seems pretty robust on paper. (Few have ever heard it.)
To get to this point the FCC would have to act as it did with TV and set a date when stations would change to digital only. There is no sign that this is happening. As to how much better even this would sound is questionable, as the FM system invented by Col. E. Armstrong in the 1930's, and given the laws of physics and human hearing, is fairly hard to beat. Other hybrid systems have been tested and work better than Ibiquity's system (DRM and others). The problem is, they only require a $10,000 or less outlay from stations, and of course leave the connected Ibiquity out of the payment loop, so they are not in the running. Digital-only FM radio would also be quite energy efficient.
Q: Can't HD radio display title and artist info?
A: Yes.....
...as can analog FM, on the majority of car radios made since the early 2000's and many other radios. WNRN broadcasts this data embedded in our signal. Crutchfield or Stereotypes can find you a car or home radio with this feature at low cost.
