Have had the JVC 850 for a while, have liked but not loved them. Was using decent sources...Fiio X3, alone or with ALO X3, or iPod touch, found it a bit "thick" sounding, not as open as I would like (the Sony H3 hybrid was much better in this regard). Changed source, iBasso DX90, better, not quite there for me. I recently got a UE900, comes with an airplane adapter that cuts back output, also good for high output headphone amps. Last piece of the puzzle, have a Ray Samuels HR-2 near my bed, great for full size phones, uneven for iems as you'd expect. Just plugged the woodies into my HR-2 through the attenuator,holy macaroni!! (had a very similar reaction to the Thinksound On1 before and after getting the Geek Out 1k,the On1 through the GO1K knocked me out in a way it hadn't before with lesser sources). The woodies became open, wide, slightly less lush instrumental timber, but more than rich enough. Seems to.me these really like an amp that grabs them by the kahankas and takes control. Synergy, synergy,synergy, makes such a difference.
Congrats on the acquisition, Drblue, enjoy...hope you're having a blast on birthday weekend!!!