Originally Posted by scud133
Here's my PSA for the day: HD radio sounds awful. Regular FM sounds more pleasing.
HD has a more extended top end, but the problem is that it's distorted and crunchy like an old low bitrate MP3.
When you switch back and forth between the same station on FM->HD, you can tell it gets more "open" and "clear" on the HD version, but the god awful top end is not worth it. It's painful to listen to, like a wall of white noise floating on top of the track.
In comparison, FM's lesser frequency range is actually an advantage because it sounds warmer, more pleasing, more soothing, whatever. It doesn't have that washy, grating top end.
HD Radio should sound worse! It's even marketed as "near-CD quality". Near? We've be passed CD quality for quite some time. It's heavily bit-rate reduced with a lossy compressor.
FM is theoretically flat to 15KHz minimum, 17KHz maximum. Either way, it's actually quite good. Good tuners had an unweighted S/N of 70+ dB in stereo, the best ever nudging 82dB. No, it's not a CD, but if you apply weighting to the noise measurement, it's darn good. In fact, because of the limited dynamic range of the listening environment, and more than a bit of self-aggrandizing fanaticism, stations typically over process their audio for both FM and HD.
HD Radio is a bill of goods sold to broadcasters, then to consumers by a hand-full of zealots. It's not better than well received FM, it's compression system is audible, the more HD channels a station uses, the worse they all sound, and there are so few HD radios in the wild that it seems ridiculous for a station to spend a quarter of a mil to add HD. They can't make a dime more money off of it either.
Guess what you get out of your radio when the HD radio stream is corrupted by signal reflections to the point it can't be received? Oh, it falls back to good ol' FM.
But wait, there's more! Did you know that the addition of a HD signal to an FM station degrades the FM? Yup. Information theory at work. Add more information in a band-limited channel, and the recovered analog signal gets noisy.
HD Radio (we should the the HD removed, it's simply not true) should never have been done on the same channel as the analog station. And, for it to really succeed it should have offered buyers something they would preceive as an unmistakable improvement (it doesn't). More crappy channels isn't the answer. Outside the FM band it could have been a cellular type system, it could have provided broadcast 5.1 audio, it could have had receiver-based processing, all sorts of great things. Thank the NAB and the FCC for locking it into the existing bands.
HD Radio is hobbled, expensive, and pointless. Radio, in general, is nearly into a tail spin.
Whew. I feel better now. Thanks.