Hey guys, maybe I missed something in these 83 pages... But I was wondering what is going on with the upsampling function?
I've been measuring the XONAR E1 over the last few days with RightMark, and have noticed some really odd behaviour.
With the newest firmware and Win 8 drivers (18.104.22.168 / 1.27 / 0111), this is the frequency response at 16/44 with & without upsampling using the USB interface:
Okay, now check the TosLink & Coaxial inputs at 16/44:
Wow! With the upsampling button on, the frequency drops off in a big way by 15kHz on both TosLink and Coaxial digital inputs for some reason!
Lets now check out USB 24/96:
Again, premature drop off in frequencies with upsampling turned on; this time at ~25kHz which arguably is inaudible at least...
ASUS: Can you discuss what kind of algorithm is being used when upsampling is turned on? Some kind of minimum phase filter upsampling for example could be very interesting! I think it's fair to say that the drop-offs in the TosLink and Coaxial at 16/44 are "bugs" since this would be audible (maybe the engineers over there should check 24/96 and other sampling rates also)! As for the drop off with USB 24/96, is this intended?
Edited by Archimago - 1/30/13 at 9:55pm