"As of May 2009, there were more stations in the world on the air with HD Radio technology than any other digital radio technology. More than 1,700 stations covering approximately 84% of the United States[4] are broadcasting with this technology, and more than 1,000 HD2 and HD3 multicast channels are on the air."
Of course, what Wikipedia's article looking like it was written by an HD radio salesman, doesn't point out...
Is that with mergers and acquisitions and the general trend toward nationally syndicated shows, or as few local radio personalities as possible, all pursuing weak advertising revenue because no one is tuning in... a true vicious cycle...
... most of the HD subchannels are simply simulcasting something everyone can already get. Because more channels didn't equate to more content on broadcast radio, for the most part.
An example here locally would be that we have one 50,000 Watt AM station that's a newstalk format, who's studio feed is also simulcast on not just one, but two HD FM stations.
It didn't add to their coverage footprint at all, with a 50,000 watt monster signal available on AM.
About all you get is a slightly higher quality bandwidth, and that is marred by digital dropouts in any kind of hilly or mountainous areas, while AM gets a little quieter if at all.
So yeah, tons of FM (and even AM) "HD" radio, but with most channels just being simulcast, it appears to have generally been wholly unnecessary for stations owned by the same corporations to even buy it.
AM station going from AM analog to Stereo/HD mode on my car decks, is the most interesting transition. Huge change in sound
There's one station locally who uses their HD sub carrier to do something awesome. They have a series of acoustic studio sessions with bands and single artists as they travel, and they dedicated one of their subcarriers to that music library, 24/7/365 without commercials. That's nice!
