The following is not necessarily the opinion of anyone else including the station named in these screenshots… however, I can assure you that a great majority of broadcast engineers agree with it.
“HD Radio” is complete and total bullshit.
What is HD Radio? Basically, it was iBiquity’s attempt to enhance AM and FM broadcasting by adding the ability for a station to incorporate additional digital audio streams to their signal, which can be decoded using a compatible radio and offer the listener additional programming choices… and in theory, offer the station an additional source of revenue, as ad space can be sold on the alternate programming as well.
What did it turn out to be? A colossal clusterfuck. That’s what. I can say fuck on the internet without having to hit the dump button, right? 😉
Here’s what’s wrong with “HD Radio” [Heavily Distorted, Highly Deceptive, Horribly Derpy…]
1) Royalties. iBiquity charges broadcasters $25,000 for a license to broadcast in “HD”. Does a station ever recoup that? Probably not. In addition… this is just for broadcasting the same audio you have on your primary analog program in compressed digi-poo. Want to add an HD2/HD3 additional program? That’s fine…. but you have to pay iBiquity a monthly licensing fee that’s somewhere in the low four figures. See Translator Abuse below.
2) Receivers. HD Radio is a totally closed, proprietary system. To decode it, you need a chip licensed by iBiquity. Some of the first ones I had the misfortune to play with drew up to 30 watts of power (I’m totally serious…!) and required a heatsink the size of a sandwich. Newer ones have improved, but their market penetration has not. You still have to pay at least $30 for an HD receiver. They’re being integrated into SOME car stereos and stuff, but it’s just not out there enough. Soooo how are ad sales going on that medium, where nobody can actually listen to it? Flatter than the compressed audio.
3) QRM!!! [QRM = interference from a manmade source]
HD radio places streams of data in spectrum that SHOULD be empty. This includes guard bands in the FM stereo composite that includes the monaural and l/r difference channel used for normal analog stereo. Some receivers will hiss as a result. In addition, as you can see in my screenshot off a Harris FrustraMatic— I mean, FlexStar HD exciter’s self-monitoring spectrogram, it makes the FM channel wider on the dial. This can make reception of a station on the next adjacent frequency impossible under some circumstances.
AM IBOC/HD radio is even worse. I don’t have a spectrogram of that nightmare handy, but what it looks like is this: the AM audio signal is bandwidth limited to 3 khz, making it sound like you’re listening over a distant telephone or something, and socked in by two solid bands of pure hash. This unyielding block of junk makes reception of distant analog signals impossible; it makes a more effective radio jammer than even that bubbly sounding thing Cuba uses! Reetch.
4) TRANSLATOR ABUSE!
A quick description: A broadcast translator is a special station used to fill in a gap in a radio station’s coverage area, or to expand its coverage where it is impractical or impossible to increase the primary transmitter site’s coverage. It works by RECEIVING the primary broadcast off the air and retransmitting it on a different frequency. I’ve installed two of these to extend WRGP-FM at Florida International University so you can actually hear the university’s radio station on their campuses – the primary signal comes from far away in the middle of a farm in Homestead and doesn’t otherwise reach very well.
For whatever reason, a couple of our major friendly radio conglomerates figured out that the letter of the law can be bent to allow them to use an analog output translator fed by an HD2/HD3 stream off of another station they own in the same market as if it were a completely new station. It’s so much easier to buy up an unused translator license or apply for one than it is to go through the FCC auctions to get a new broadcast station license, so they’ve been doing that…. There’s a reason we call them Cheap Channel…
Nowadays since sales of HD Radio software licenses are flat, iBiquity has actually been PROMOTING this. Okay, how about no.
5) Audio quality. It sounds HARSHLY compressed. If you’re using the HD2, and heaven forbid, the HD3 subcarriers, they REALLY suffer.
6) LET’S DO THE TIME WARP AGAIN! It takes a few seconds to compress and process the audio for the HD channel, thus, you have to delay the analog audio to match up so that a listener does not experience horrible time skips that make the station unlistenable whenever their receiver switches between digital and analog. The equipment to do this, the HD “Exporter”, is… uhhh… special. It seems almost like it was tacked on as an afterthought, and when it gets out of sync (and it will), your listeners are in for a treat. It’s about as pleasant to listen to as it was for me to wear this giant quarter-pound Teflon feedline spacer as an ear cuff. You know… I think there’s a general “making really disapproving faces at things in radio stations” theme going on here as of late.