They are formatted for the web as specs - not as an example of the sound - an example of some of the content Clear Channel is using.
The HD Radio format on FM has the same codec as XM but with a higher bitrate - and Sirius's codec just sucks wind even to XM. They won't pay to upgrade it.
That's just one Company - Clear Channel's lab for additional formats - and their stations are doing HD2 formats not even listed there already in various markets.