Quote:
Originally Posted by
jacknight 
so E12 will have great power, just say, do you think it will drive HD650 well?
Maybe this is for FiiO to answer, but just for reference, with 6 AAA li-ion 10440 batteries, E12 could theoretically reach the power levels of the E9. It depends on the output they design.
As for driving certain headphones well, I don't really like that phrasing. It depends on how loudly you listen, your expectations, and your preferences. For many purposes, one could say that the E11 already drives the HD 650s very well, or even the E6.
Quote:
Originally Posted by
feiao 
Is this kind of potentiometer is acceptable ? it can help control the thickness, we are worry about the quality of such kind of potentiometer.

Are you worried about mechanical quality or electrical quality? I think that a sturdier, higher-performance option with better tracking is important for a product above $100. An Alps, as originally mentioned, should probably be okay.