"Streaming Audio' vs. HDRadio

You are probably right in that the streaming ausdio feed is dependant on what it must go through to get here. I am sure that DSL would help a bit. Another factor would be that a streaming audio feed is quite compressed.

HD radio is pretty much brand new. That's why there are so few receivers. Of course, it may not catch on. We'll have to see.

Streaming audio, HD radio, and satellite radio are all compressed. Their relative quality depends on how compressed they are and what codec they use. In the case of HD radio, there is also the matter of signal strength. If it's too weak, it reverts to analog (which probably won't be that great, either).

The determining factor here is definitely the bitrate of the stream. If you have dialup, it's impossible to get a high quality stream as the bandwidth just won't support it. My experience is a 64Kb stream is listenable on computer speakers at work, but on my big rig it has to be at least 128Kb to be enjoyable. If you use iTunes, all the radio stations there have the bitrate indicated - you can experiment and hear the differences at the different speeds.

If you want to hear what streaming radio could sound like in a perfect world, listen to KWVA:

http://gladstone.uoregon.edu/~kwva/kwva.ram

They stream RealAudio at 320Kb! The stream is WAY better than their broadcast signal and with my cable modem Internet access I never have dropouts. Pure college radio joy.

David

The determining factor is not just bitrate. It's also the choice of codec. 48kbps AAC+ will sound significantly better than 64kbps MP3. XM, I believe, uses the former.

All things being equal, of course, more bits is better. And I'd certainly expect 320kbps anything to outperform over-the-air radio.

Pabelson,

While I agree the choice of codec makes a difference, the problem is we rarely get to make that choice in the streaming radio world. I agree that at the same bitrate, AAC beats MP3 - Ogg Vorbis probably beats both. But I'm not aware of any free Internet stations (or even pay ones) that use AAC. Generally they use one of either MP3, Real, or Windows Media - occasionally they'll offer two of the three. KWVA used to offer 192Kb MP3 and 192Kb Real, but the Real stream sounded so much better that all their users (including me) flocked to it, so they reallocated their bandwidth as 64Kb MP3 and 320Kb Real.

The biggest problem with Internet stations is they tend to be run on a shoestring, so they come and go at a pretty rapid rate. Maybe we should call that the biterate. :-)