Not off the top of my head. I will see if I can find it though. It wasn't official tests, just guys posting findings in a thread. If you have the gear, try the test. Depends alot on the soundcard and receiver you have. If you are using a onboard as a link to a receiver, your getting the best sound possible. How ever if you have one of the newer cards you may find your set up will sound much better using analog connections over digital. Test for yourself.
Bookmarks