I consider this an important feature due to my hearing limitations.  One reason I love Rock boxed players.  Can someone suggest which players include balance control in the UI? I know Fiio does on most of their models,  curious about some of the newer players.  I'm waiting on the Echobox, but...

And how many are in "regular rotation", say 1 day a week?   Six pairs for me, 3 in regular rotation.   The other three are worthy as well, just not as good as the top 3.  I should probably switch up a little more, the ones not in regular use may sound different / better than I remember them...