This weekend I decided to try out the USB input on my JVC D201. When I first connected my computer to the JVC, the computer detected the JVC and installed a USB DAC software driver. However, I could not get any sound. I fooled around with every setting I could find on the PC and everything looked good. I was about to give up when I saw a line in the JVC manual that stated that if there is no sound you might try rebooting your PC. Ah yes, I should have thought of that, the magic cure for everything. Fricken Winblows. After the reboot, it worked perfectly.
So now I had to do a comparison to see if the hard drive USB transport would work any magic in my system. I was using a Panasonic D27 feeding the JVC via analog inputs as my comparison source.
The two sources were very similar sounding. I believe that the Panasonic DVD sounded better than the harddrive USB setup. The harddrive USB setup had a sound that just seemed a little thinner. That is all the notes seemed to lack some bass support.
The JVC also has an SPDIF coaxial interface. A couple months ago I had compared this digital interface vs the analog interface when connected to the Panasonic DVD. The two interfaces were very close in sound quality. I give a slight edge to the analog input again. However, it is so close, I really could not say why I preferred the analog.