The annual NAB Show in Las Vegas is now behind us, and with it a bevy of announcements regarding HD Radio, the U.S. digital radio standard:

1. More test-results were announced regarding the workings of all-digital AM-HD Radio. Not many details: additional stations have conducted field-tests, and while the digital signal does sound better than the analog and hybrid analog/digital ones, it’s not as robust as hoped, leading many in Vegas to believe that, if the FCC does authorize the use of all-digital AM-HD this year, it’ll be for the daytime only.

The FCC and industry tried the same approach more than a dozen years ago when it first approved the HD system; will it work better the second time around? AM broadcasting is in a much more vulnerable position now, with some broadcasters forecasting the beginning of the end for the band before long. The FCC is expected to move on its AM revitalization initiative relatively soon.

2. iBiquity announced the construction of a “monitoring network” designed to identify stations whose implementation of HD Radio is not optimal, which often leads to signal dropouts, dead air on FM-HD subchannels, misalignment between a station’s analog and digital signals, and power/interference issues. It claims this network is now operational in the nation’s top ten markets and will be rolled out to the top 50 over the course of this year.

3. iBiquity also announced more automotive models have added HD Radio reception capability. Still, no manufacturer save BMW has committed to offering HD as standard equipment across its entire fleet; by and large HD remains sequestered as a feature in automotive infotainment packages, many of which reside only on higher-end models. (Nearly all now include the ability for drivers to disable HD reception.)

4. Radio Disney – which sold off all but one of its radio stations last year – announced it’ll continue providing broadcast content via a network of FM-HD subchannel affiliates. This is part of a larger effort by iBiquity and its broadcast-investors to sell more ads on FM-HD subchannels. Sounds like a win-win: Radio Disney gets to continue to promote itself as a bona-fide broadcast network, while a few dozen affiliate-stations get to add a syndicated channel to an otherwise moribund national HD-only programming menu.

Yet, as it has been for the last dozen years, none of this news does much more than generate some signs-of-life that iBiquity and its investor-broadcasters can use to stave off talk of any technological competition to or replacement of HD.

Contrast that with developments out of Norway and the United Kingdom, which adopted the out-of-band DAB/DAB+ system. Norway recently announced it has achieved the preliminary metrics to discontinue FM analog broadcasting in 2017. As Paul Riismandel at Radio Survivor has noted, it’s an important milestone for the DAB+ system but not a bellwether in terms of a mass analog/digital radio transition in the making.

All the conditions have come together just right in Norway for a transition-deadline to be seriously considered. The country’s topography is hard on analog radio signals. Its population-density and distribution makes planning a network of DAB+ transmitters to serve the country a relatively straightforward exercise. And most importantly, Norway’s radio industry isn’t that large, and its most powerful constituents are public and state broadcasters, who’ve been quite supportive of digital radio from the outset. As a result, digital program diversity has positively exploded relative to what the analog radio dial presently contains.

Still, there’s a lot that could happen between now and 2017. For one thing, Riismandel also notes that many independent FM broadcasters plan to stay on the air after the planned switchover, and they’re mounting a lobbying campaign in Parliament to allow analog and digital radio to co-exist indefinitely.

Meanwhile, in the United Kindgom (a DAB first-adopter), analog/digital transition deadlines have been pushed back repeatedly (2019 is the current hope). However, the UK built out its DAB network in two tiers – one with transmission multiplexes owned by the BBC, which carry only BBC services, and one with multiplexes auctioned off to the highest bidders for the use of private broadcasters, who effectively rent their channels on a multiplex transmitter. This has dramatically inflated the costs of access to the DAB system in many parts of the UK, and multiplex operators have opted to cram as many channels as they can onto every multiplex, degrading the sound quality of the channels they carry.

This has led Ofcom, the UK’s radio regulator, to open up experimentation with small-scale, stand-alone DAB stations to increase program diversity – effectively replicating an element of the analog-model of station-placement on the digital bands. More than 50 local and community broadcast stations applied to be a part of a trial-run of these stations, of which Ofcom plans to set up ten over the next nine months. The tests may involve small-scale multiplexing as well.

While pundits with skin in the industry will tell you that comparing digital radio technologies is an apples-to-oranges affair, this does not apply to examining their relative progress. In Europe, DAB/DAB+ is demonstrably making new radio, expanding program diversity on the dial and pioneering new ways to use digital spectrum; analog broadcasting – still a mainstay – is utterly complementary to this process. In the United States, digital radio is a black-box bolt-on component sharing spectrum with the existing analog regime, effectively replicating its inherent inefficiencies and bereft of any room to innovate. The pattern of progress tells the tale: one is now identifiable while the other is not.