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An HD Radio Deployment Scorecard

As we approach the annual media pilgrimage to the American desert known as NAB2007, it's a good time to take the pulse on progress of the U.S. radio industry's transition to digital broadcasting.

As we approach the annual media pilgrimage to the American desert known as NAB2007, it’s a good time to take the pulse on progress of the U.S. radio industry’s transition to digital broadcasting.

There has been considerable activity in the space recently, and every indication of an upward trend. Nevertheless, it does not appear that HD Radio has yet reached the critical mass required to drive it toward mainstream adoption.

What follows is a list of the most important issues facing HD Radio at the moment, and thoughts on their impacts and possible resolutions.

In good form

To date, HD Radio devices have been almost exclusively packaged as car or tabletop receivers. Given that radio arguably is the most broadly available medium, and is used by Americans in nearly equal amounts at home, at work and in transit, all forms of radio receivers need to be offered with HD capability.

The lack of portable receivers has been addressed in this column and elsewhere, with acknowledgment of the particular challenges for that form factor. It is heartening to know that current developments may make practical the deployment of portable/handheld HD Radio receivers soon.

Another form factor that remains largely missing to date is the home hi-fi receiver or component tuner. This would seem to be one of the most appropriate forms in which to showcase HD Radio’s audio quality, but few such devices have emerged.

Let’s hope that by next NAB, this argument will be moot, and we will see HD Radio offered in car, tabletop, alarm-clock, boombox, small portable, handheld and hi-fi component receiver devices.

Buzz or bust

There are two paths to ultimate success: a short, direct route, or a long and winding road. It’s still too soon to tell which HD Radio is on (if either), but the latter seems more likely today. There has not yet been any indication of the “killer-app” groundswell of support for HD Radio that would propel it to quick, must-have status. On the other hand, it seems plausible that radio stations will continue to deploy the service to near-universal proportions, and that most radios eventually will quietly include the technology.

In this respect, HD Radio would take on the status of FM stereo or color TV, each of which started relatively slowly, but experienced a slow yet steady growth in popularity until they ultimately became the norm.

If such a scenario proves true for HD Radio, it calls into question the future of many multicast services. A slow transition could eventually make “HD-1” the mainstream FM audio service, but it might not provide an adequately robust market for “HD-2” services and beyond to flourish. (Such services might still manage to survive as hybrid on-line/on-air-multicast streams, however.)

Another eventual benefit of near-universal HD Radio deployment by broadcasters — regardless of consumer HD Radio receiver uptake — is the datacasting marketplace. Recent activity has shown interest in non-program-associated data (NPAD) delivery, which could prosper in a wholly separate, private environment, and provide a bit of a silver lining for broadcasters’ ROI in even the darkest skies of consumer uptake for HD Radio.

Rules of the road

HD Radio also needs to emerge from the shadows of interim rules. Let’s hope the long-awaited final rules for the format will be on the books before another year passes. This is of particular importance for HD AM, where much uncertainty remains.

Meanwhile, there are other rules being considered that might apply to HD Radio products that would not be welcomed by most of the industry. These involve limits on recording and the subsequent storage, editing and playback characteristics of devices that capture content delivered via HD Radio. Currently such limits are being considered by the U.S. Senate for satellite radio (the so-called PERFORM Act, S.256), but the music industry representatives who are lobbying for such legislation have made it clear that they would ultimately like to see similar limits applied to digital terrestrial radio broadcasting.

Metadata matters

A retrospective look at RBDS reveals that it provides more “service metadata” than “content metadata,” meaning that it tells more about the radio station and its service stream’s attributes than it does about the current content being broadcast on the stream. While service data is valuable and important information, consumers have come to enjoy the title and artist or other PAD provided by satellite radio and other digital media forms, which RBDS does not provide in any standardized way, having no dedicated fields for these purposes.

Various attempts to retrofit content metadata into RBDS have been attempted, including the current RT+ proposal, but HD Radio includes such information in standardized form from the start, using the well-established ID3 tags from the MP3 format.

This provides HD Radio with a largely unheralded additional advantage over FM (although if RT+ succeeds, FM analog service may ultimately match these capabilities).

In any case, it makes sense for both broadcasters and radio manufacturers to promote this feature, with careful delivery of rich and complete content metadata by stations, and attractive and comprehensive display of content data on receivers.

HD should be better than analog

A troubling phenomenon has been reported by some listeners in these early days of HD Radio. Consider that because all HD Radios first tune to the analog service then switch to digital service with some concurrent visual indication, listeners have a very clear way of comparing the services. In most cases, a noticeable change in audio quality accompanies the switch.

One would assume that this quality change is in the positive direction, but in some cases on FM HD, the opposite occurs. This is due either to differences in audio processing, or in the case of multicasting, the bit rate assigned to HD-1 service is inadequate to make it sound as good as the analog FM signal. In other cases, this causes the HD-1 service to sound no better than the analog, which is almost as undesirable an outcome.

Similarly, there are stations today that are pumping out plenty of data via RBDS but are not yet doing so via HD Radio PAD. In these cases, a listener will see this metadata during the FM tune-in period, or during analog blending, but as soon as an HD signal is acquired, the metadata disappears! Naturally, neither of these cases sends the message to consumers that HD Radio is an improvement over analog FM.

Of course, these are interim, short-term problems that easily can be remedied by stations as the HD Radio transition matures. But as the saying goes, you never get a second chance to make a first impression, and such experiences may create long-term, negative conclusions about the value of HD Radio for some listeners.

Broadcasters should therefore ensure that HD-1 service sounds noticeably better than analog FM, and that the metadata experience is at least as good, if not better from HD-1 PAD than it is with RBDS.

Future features

While we’re at it, it would be nice to finally see real deployment of the long-promised storage receivers with pause/rewind buffers and programmable recording capabilities for HD Radio. A related new capability for both broadcasters and users is an electronic program guide (EPG) format for HD Radio.

Also on the wish list is standardized encryption to enable subscription radio services via HD Radio multicasting.

So on balance, while the transition is now well underway, there is still much to be done.