HD radio?

Scott Fybush scott@fybush.com
Sat Jan 22 19:55:51 EST 2005

>The claims of the AM-band version sounding as
>good as (analog) FM and the FM-band version sounding as good as a CD are
>largely the product of the fertile minds of PR people.

I've spent the last several days visiting a number of radio stations in the 
New York City market, including WOR, where I first heard IBOC a few years 
ago and where I've been returning on a fairly regular basis to listen as 
the codec improves.

The last time I heard WOR's IBOC audio was in 2003, and it sounded like a 
low-bandwidth web stream, with all the swishing and artifacts you'd expect. 
It has improved dramatically since then. While I didn't have time to give 
it a real critical listen, it sounded as good to me as a typical FM 
station's air signal these days, stereo and all. (And yes, there's music on 
WOR - they're fairly heavy on it during their local shows, and they've 
redone all their imaging elements, even the top-hour time tone, to be in 

Where the last codec I heard fell apart was on voice. The current version 
handles talk quite well. I didn't listen long enough to see if there was 
any fatigue from this codec, but it sounded as though it would be 
listenable for the length of an average commute.

But - and this is a tremendous honking "but" - WOR has the signal to pull 
it off. There's nothing anywhere nearby on 700 or 720, and nothing of 
significance on 690 or 730. And WOR pumps something like 300 kW ERP toward 
Manhattan. What works for WOR won't work for 580 Worcester/590 Boston, say, 
or 1400 Fall River/1410 Brockton/1420 New Bedford/1430 Everett/etc.

>The advantages of digital
>transmission just aren't great enough to motivate Americans to discard
>nearly a billion radios and replace them with radios that cost (at least
>initially) several hundred dollars each.

The hope continues to be that IBOC will, like RDS, be one of those features 
that starts to become standard in many new cars. I think XM and Sirius beat 
terrestrial radio to the punch on this one.

>I don't think iBiquity's AM-band system has a chance despite its nominal
>compatibility. The strongest proponents seem to be station owners who have
>no technical understanding and who believe that HD Radio will be the
>salvation of their licenses. These folks seem to believe that if they keep
>smiling and talk up the advantages that iBiquity's press releases trumpet,
>they can make fictiion into reality. The problem is that all the optimism in
>the world can't repeal the laws of physics.

For a station like WOR, there's no compelling reason right now NOT to be 
doing IBOC. The costs of adding it, especially at a time when the station's 
building new studios and a new transmitter site anyway, are nominal, and 
the advantages are potentially pretty large. If receivers start to get out 
in the marketplace, even if they're only in a few new cars at first, the 
difference in sound quality between analog and IBOC is dramatic enough to 
be noticeable, and there's reason to think that listeners who might not 
stay long with the muffly old WOR analog sound might listen longer to the 
digital. (WOR is also now transmitting RDS-like data with its IBOC, giving 
it a degree of parity with FM RDS.)

Again, that's WOR, which already has a huge signal. A number of owners of 
much smaller signals seem to have the idea that IBOC will be a magic bullet 
that will give their 500-watt daytimer full-market coverage. They'll get a 
surprise down the road. So will the many, many stations whose technical 
plants have not been maintained as well as WOR's has been. There are a lot 
of directional arrays out there that will never be able to handle IBOC's 
bandwidth requirements.

I also believe that the FM system will work, though it won't be a raging 
success. Again, it's relatively inexpensive to implement, and especially 
for public broadcasters, it offers that coveted second audio stream. If the 
radios get out there for FM, they'll be out there for AM, too. You might 
not pay $400 for one now, and I wouldn't either, but the odds are at least 
decent that the new car you buy in 2009 will have it as a standard feature, 
and once it's there, it's there.

>If there were no requirement for compatibility, however, a good AM-band
>system could be built and the signals wouldn't have to use more bandwidth
>than existing analog AM signals. In fact, a good digital AM-band system
>exists. It's the European Digital Radio Mondiale system, which has never
>been given a chance in the US. The official reason that DRM never got a
>chance here is its incompatibility with existing radios. Although the
>allegations of incompatibility are true--and nobody associated with DRM ever
>said otherwise--politics supposedly played a role in DRM's never getting a

Of course. But one factor that gets left out of this discussion is that the 
DRM proponents never developed a system for the FM band, in large part 
because they all came from countries that have gone with Eureka-147 
instead. The FCC, and the US broadcast community, wasn't going to settle 
for a system that only worked on AM - or for completely separate AM and FM 
systems - when Ibiquity was offering a system that could work on both. It 
could have been a hell of a lot worse - imagine if the two competing 
developers had never merged into Ibiquity and we now had two separate and 
incompatible systems battling it out for public acceptance!


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