You don't need to fork up more $$$$..... There is so much crappy software and artifact-laden music tracks out there, who knows what people hear what they hear........
"2. Or high-def cannot be well appreciated with headphones."
I don't think headphones have anything to do with it.......
"3. Or the upsampling back from 16/44 --> 24/96 somehow reconstitutes the sound."
I've never heard asynchronous sample-rate conversion that I didn't think was better than mediocre...... It's usually awful.........
"4. Or, there's really not much difference."
There are too many points of degradation taking place. The RFI on PC-based systems negates the inherent advantage of 16/44- Less number crunching per unit time means less RFI. But it must be conventional playback.
Personally I think RFI is the fundamental flaw for running any listening test on a PC.
"5. At this point I'd probably spend a few more dollars to buy a high-def download (maybe at most $5-10 more if it's something I like) when given the option but not expect significantly more revelation in the sound."
I think the two issues are RFI and excessive sample rate conversions...... The only way to properly evaluate 16/44 vs. high-rez is to convert A/D from an analog source directly to the two rates directly (two separate A/D conversions), and avoid sample rate conversions altogether.
