Hey joker: Nice review and comparisons....... Would you be able to find out the actual diameter of the dynamic drivers? All the rha model doesnt carry that info and just wondering whats the secrecy in that very basic info. I even enquired about this already with our fellow mate mark2410 as he reviewed a rha iem and he even didnt have a clue about it.........just like how b**e reveals external dimensions as tech specs for their cubes and AM bass modules.
It never occurred to me to ask - I can't really learn anything about an earphone from its driver diameter.
That probably happened when the JH13 was added and everything else got bumped down. In any case I still use the ER4 all the time for comparisons so I may have felt it needed a bump against things occupying the lower 9.x range these days.