That's an interesting observation: will you hear a difference if you listen via the E11K? I wonder, as I used to own an E09K, it was merely a good amp, not a great amp. To the guy who posed the question, does an X5iii sound substantially better than an X5iii? I suppose you'll get a better answer in the X5iii forum. I wouldn't mind knowing the answer myself as I have an X5i and have a bit of the upgrade bug!